MCAT BS SECTION
A man that is homozygous for eye color, bb, is married to a woman who is heterozygous at the same gene: Bb. What are the chances that a child will have the Bb genotype and be a boy?
25% All children must receive at least one b allele from the father, and 50% will receive the B allele from the mother; so 50% of the children will be Bb, and the odds of a boy are 50%. 0.5x0.5 = 0.25
If the frequency of the G allele is 0.25 in a population of 1000 mice, determine the number of individuals who are Gg heterozygotes, provided all of Hardy-Weinberg's assumptions are present.
375 frequency of G allele (p) is 0.25, then the g allele (q) must be 0.75 (p+q=1) The frequency of the heterozygotes in the population will be 2pq= 2(0.25)(0.75) = 0.375 x 1000 mice = *375*
How many spermatozoa or sperm cells are formed from a single spermatogonium?
4
What is oxygen pressure in body tissues, and what is the result?
40 mmHg. - thus, as blood moves through the systemic capillaries, oxygen diffuses to the tissues (from high to low pressure), and carbon dioxide diffuses to the blood.
How many chromosomes exist in the nucleus of a human cell?
46
How many bacteria can a single neutrophil phagocytize?
5 to 20 bacteria
Difference between NADH and FADH2 in regards to ATP production in the ETC
2-3 ATPs for each NADH. FADH2 reduces a protein further and produces about 2 ATPs
What are the purines?
2-ring structures: adenine and guanine
How many cycles per glucose molecule in aerobic respiration? (krebs cycle).
2.
If a polypeptide contains 100 amino acids, how many possible amino acid sequences are there for this polypeptide?
20¹⁰⁰
Where is the 5' UTR and the 3'UTR?
5' UTR: located between promoter and TSS on coding strand 3' UTR: located between stop codon and termination sequence on coding strand
What is 5'capping and 3' poly-A tail?
5' capping and 3' poly-A tail: these help to protect the RNA from degradation so they can last longer.
In what direction is a sequence of RNA nucleotides written?
5'→3'
In which direction is the nucleotide sequence in DNA written?
5'→3', downstream, Since DNA is complicated, reading it is like paddling upstream, 3' to 5', while synthesizing it is paddling downstream from 5' to 3'.
If an individual is heterozygous at the color gene, Gg, and heterozygous at the shape gene, Ww, what are the chances that a gamete containing the G allele will also contain the W allele? Why?
50% According to independent assortment, the segregation of one gene does not depend on segregation of another. The chances of a gamete containing the W allele are 50% regardless of the color allele.
What does a shift the the right of the Oxygen Dissociation Curve indicate?
A lowering of Hemoglobin's affinity for oxygen - Right shift= less bound O₂
Proteoglycans
A mixture of proteins and carbs, but generally have more than 50% carbs
What is the main difference between glycolysis/krebs cycle, and ETC in regards to ATP?
ATP is produced in glycolysis and the krebs cycle via substrate level phosphorylation whereas in the ETC its oxidative phosphorylation.
What is it called when there is a deletion or duplication of entire sets of chromosomes?
polyploidy
Transcription requires a promoter, whereas replication requires a _____?
primer.
Which amino acids is the helix breaker?
proline
fixing carbon dioxide
reducing carbon dioxide and using the carbon to create organic molecules usually though the Calvin cycle
What is the major function of steroids?
regulate metabolic activities
Complementary strands:
relation between two nucleotide strands of DNA in which each purine on one strand pairs with a specific pyrimidine on the opposite strand - A and T; C and G
exocrine glands
release enzymes to the external environment through ducts
What are regions of non-coding DNA found only in euks called?
repetitive sequence DNA
What is the point where a replisome attaches to the chromosome called?
replication fork
DNA is produced by _____; RNA is produced by _____.
replication; transcription
microfilaments
responsible for contractions in phagocytosis, cytokinesis, microvilli, and muscle
What is the main purpose for centrioles, asters, and spindles?
responsible for pulling apart the sister chromatids during mitosis
What is an advantageous mutation, and give an example of this.
results in a benefit to the fitness of the organism. For example, the mutation that causes flies to become wingless is advantageous in an environment that is very windy.
Describe a deleterious mutation. What is an example of this?
results in a harmful effect to the fitness of the organism. For example, a mutation that causes an organism to be sterile.
What is scenario 2 of a double crossover?
results in genetic recombination. The chromatids exchange alleles during a crossover. Then, one of the crossover chromatid exchanges with a different chromatid. This is called the 3-strand double crossover. Results in 2/4 recombinants.
trc is 10 times _____ than DNA replication
slower
Where does 90% of digestion and absorption occur?
small intestine
What is the complex that removes introns from mRNA in the nucleus?
small nuclear ribonucleoproteins.... snRPS
fovea
small point on the retina containing mostly cones; vision is most acute at this location
virioids
small rings of naked RNA without capsids; only infect plants
gap junctions
small tunnels connecting cells; allow small molecules and ions to move between cells
Which type of motor units are the first to be activated?
smaller
chemoreceptors
smell and tate are detected by ___
astrocytes
star-shaped neuroglia in the central nervous system that give physical support to neurons and hep maintain the mineral and nutrient balance in the interstitial space
FSH
stimulate sertoli cells to surround and nurture the spermatocyte and spermatids
LH
stimulate the Leydig cells, which release testosterone
What is the major function of phospholipids?
structural component of membranes
A lyase that catalyzes addition of one substrate to a double bond of a second substrate
synthase
gluconeogenesis
synthesis of glucose from lactic acid and noncarbohydrates, Catabolism of amino acids and glycerol into glucose for energy.
rough ER
synthesizes virtually all proteins not used in the cytosol
sympathetic, parasympathetic
systems of the motor portion of the ANS
Which form of RNA has an anticodon and what does it do?
tRNA contains the anticodon which is a set of NTs that is complementary to the codon. tRNA sequesters the amino acid that corresponds to its anticodon and transports it to the rRNA complex
What are the 2 ends of the chromosome
telomeres
In meiosis, at what point are cells officially considered to be haploid?
telophase I
At which level are prok genes activated or deactivated?
transcription, via activators and repressors
Nitrification
two step process that creates nitrates from ammonia NH₄⁺ + 1.5 O₂ → NO₂⁻ + H₂O + 2 H⁺ NO₂⁻ + 0.5 O₂ → NO₃⁻
pinocytosis
type of endocytosis in which extracellular fluid is engulfed by small invaginations of the membrane; performed by most cells
phagocytosis
type of endocytosis in which the cell membrane protrudes outward to envelope and engulf particulate matter after proteins on the matter bind with receptors on the cell; only some cells can perform this type of endocytosis
Schwann cells
type of glial cell that produces myelin in the peripheral nervous system
Human growth hormone (somatotropin)
type: peptide Origin: anterior pituitary function: growth of nearly all cells increases episodes of mitosis, cell size, rate of protein synthesis, mobilizing fat stores, increasing the use of fatty acids for energy, and decreasing the use of glucose increases amino acid transport across the cell membrane increases translation and transcription decreases the breakdown of protein and amino acids
Thyroid-stimulating hormone (TSH)
type: peptide origin: anterior pituitary function: stimulates the thyroid to release T3 and T4 via second messenger system using camp increases thyroid cell size, number, and secretion rate T3 and T4 have a negative feedback effect on TSH
LH
type: peptide origin: anterior pituitaryy function: causes ovulation; stimulates estrogen and testosterone secretion
glucagon
type: peptide origin: pancreas alpha cells function: increases blood glucose levels stimulates glycogenolysis (breakdown of glycogen) and gluconeogenesis in the liver
insulin
type: peptide origin: pancreas beta cells function: lowers blood glucose levels stores carbs as glycogen int he liver and muscles fat is stored in adipose tissue amino acids are taken up by the cells of the body and made into proteins
antidiuretic hormone (ADH); also called vasopressin
type: peptide origin: posterior pituitary function: concentrates and reduces the amount of urine causes the collecting ducts of the kidney to become permeable to water
Calcitonin
type: peptide origin: thyroid function: decreases blood calcium by decreasing osteoclast activity and number
prolactin
type: peptide origin:anterior pituitary function: promotes lactation by the breast
cortisol
type: steroid; glucocorticoid origin: adrenal cortex function: increases blood glucose levels by stimulating gluconeogenesis in the liver degrades adipose tissue to fatty acids to be used causes decrease in cellular glucose use causes degradation of nonhepatic proteins anti-inflamitory
aldosterone
type: steroid; mineral corticoid origin: adrenal cortex function: increases Na+ and Cl- re-absorption and K+and H+ secretion in the collecting tubule of the kidney
parathyroid hormones
type:peptide origin: parathyroid glands attached to the back of the thyroid function: increases blood calcium increases osteocyte abosrption of calcium and phosphate from the bone increases calcium and phosphate uptake from the gut
electrical synapses
uncommon; composed of gap junctions between cells; don't involve diffusion of chemicals; transmit signals faster than chemical synapses and in both directions
Nearly all ammonia is converted to
urea by the liver and then excreted in the urine by the kidney.
Nearly all ammonia is converted to ____ by ____ and then excreted by?
urea; liver---> then excreted in the urine by the kidney
bile produced by? stored in? function?* Why is it necessary?*
Liver; gall bladder. -Emulsifies fat meaning it breaks it up into small particles without changing it chemically -To increase surface areas of fat so the lipase can degrade it
Is height polygenic or pleiotropic? Why?
Polygenic because it is influenced by many different genes, including genes for growth factors, receptors, hormones, bone deposition, and so on.
When a substrate changes the shape of the enzyme allowing other substrates to bind more easily
Positive cooperativity
________ occurs when the product returns to activate the enzyme.
Positive feedback
In Euks, each type of RNA undergoes...
Post transcriptional processing and this allows for additional gene regulation
What are lysosomes? What do they do?
Lysosomes are vesicles containing hydrolytic enzymes that digests things like food and viral/bacterial particles. Things you want to digest gets into a vacuole by endocytosis or phagocytosis, and then the vacuole fuses with the lysosome. Anything inside gets digested by the hydrolytic enzymes.
Kupfer cells
Macrophage cells in the liver that are responsible for destroying old erythrocytes.
What do agranular monocytes mature into?
Macrophages
Cardiac muscle is excited by?
Increased cytosolic calcium concentration.. that is because all muscles contract in response to increased cytosolic calcium concentrations.
How is a ligase different from a lyase? What are lyases sometimes called?
Ligases require energy from ATP or some other nucleotide, and are sometimes called synthetases.
Envelope
Lipid-rich envelope that is either borrowed from the membrane of their host cell or synthesized in the host cell cytoplasm Typically contains some virus specific proteins Most animal viruses, some plant viruses, and few bacterial viruses are surrounded by envelopes
What part of the body is capable of reforming glucose from glycogen and releasing it back into the blood stream?
Liver
Most of the glycogen in the human body is stored in ___ and ___
Liver and skeletal muscles
Is it possible to deduce the genotype of a pea plant at the color gene if it is green?
No. It could be heterozygous or homozygous
Are genes always proteins?
No. tRNA, rRNA and small nuclear RNA genes are not
Why are prok genes polycistronic and euk gens are monocistronic?
Poly mRNA includes several genes in a single transcript, where Euk mRNA have only 1 gene per transcript.
In which parts of bone is spongy bone found?
Spongy bone is typically found at the Metaphysis and Epiphysis of bone... thus at the bulbar ends of bones
How long to RBCs survive?
Squeezing through capillaries wears down their plasma membranes in about 120 days.
________ are mutagens that cause cancer
carcinogens
Why is it that the lymph nodes of the neck swell from a cold or other sickness?
They swell as white blood cells proliferate within them to fight the infection
What pattern of expression will a recessive allele on the X chromosome display in males?
They will be always expressed since no other allele can mask that recessive allele
If allele frequencies in a population are constant, and genotype frequencies can be calculated from allele frequencies, how will genotype frequencies vary over time?
They will both remain constant according to hardy-w
How are the thin and thick filaments of smooth muscle organized?
Thin and thick filaments in smooth muscle cells are attached to the intermediate filaments, and, when they contract, they cause the intermediate filaments to pull the dense bodies together.
Based on the Oxygen Dissociation curve, what does the flat area at the top represent?
This flat area shows that small fluctuations in oxygen pressure have little effect on percent saturation of Hb with oxygen.
What does the area of the curve that sharply climbs indicate?
This indicates that with small changes in oxygen pressure follow large changes in Oxygen saturation of Hb.
What is the area called and where is it located where a bone continues to grow in length?
This is a sheet of cartilage located in the metaphysis, called the epiphyseal plate.
What type of antigens and antibodies does a person with Type O blood have?
Type O blood has neither A or B antigens. This person's immune system makes both A and B antibodies
Describe the relative pressures between lymph fluid and interstitial fluid:
Typically, interstitial fluid pressure is slightly negative (gauge P). as the interstitial pressure rises toward zero, lymph flow increases.
Which type of motor units are the first to be activated?
Typically, smaller motor units are the first to be activated, and larger motor units are recruited as needed. - this results in a smooth increase in the force generated by the muscle.
What does the SRP do in translation of proteins?
carries the entire ribosome complex to a receptor protein on the ER.
Apoptosis involves the activation of _______ that digest the cell from within
caspases
Positively charged ions always move toward the _____, while negatively charged ions always move towards the ____?
cathode; anode
Incomplete dominance
When the phenotype of a heterozygote is a blended mix of both alleles, and the alleles for that trait are given different upper case letters
What is recombinant DNA?
When two DNA fragments are cleaved by the same endonuclease, they can be joined together regardless of the origin of the DNA. This is recombinant DNA; it has been artificially recombined
The 2 major hormones that affect the secretion of the stomach juices are? Function of them?
acetylcholine: increases secretion of all cell types; gastrin: increases HCl secretion
saltatory conduction
action potential jumps from one node of Ranvier to the next
out of, negative, repolarization
action potential: as voltage gated sodium channels close, voltage gated potassium channels remain open and K+ flows __ the neuron causing the inside of the cell to become more ___, a process called ____
depolarization
action potential: reversal of polarity in a neuron, where the inside of the cell is positive relative to the outside
hyperpolarization
action potential: the inside membrane becomes more negative than the resting potential
less, slower
action potential: voltage gated potassium channels are __ sensitive than voltage gated sodium channels, so they are ___ to open
actin
active in cytoplasmic streaming (amoeba-like movement)
Lymph flow in an _____ individual is considerably greater than in an individual at ____.
active; rest
Adenine forms ___ H-bonds with ____?
adenine forms 2 H-bonds with Thymine
What is glycosylation?
affects protein's structure, function, and protect it from degradation
ciliary muscle
circles the lens in the eye; when it contracts the opening of the circle decreases making the lens more spherical moving the focal point closer
Two other names for the Krebs Cycle
citric acid cycle, tricarboxylic acid cycle
What is the Lac Operon?
codes for enzymes that allow E.coli to import and metabolize lactose when glucose is not present in sufficient quantities.
*The distal tubule empties into the ____, which ___.
collecting duct; concentrates urine
iris
colored portion of the eye that creates the opening called the pupil; in a dark environment, sympathetic nervous system contracts the part of the eye, dilating the pupil
steroid hormones
come only from the adrenal cortex, gonads, or the placenta lipids, diffuse through the membrane and act in the nucleus on the transcription level formed primarily in the smooth ER and mitochondria
Give three examples of common DNA binding domains
common DNA-binding domains include helix-turn-helix (HTH), zinc finger, basic-region leucine zipper (bZIP).
neuronal communication
communication in multicellular organisms that is rapid, direct, and specific
hormonal communication
communication in multicellular organisms that is slow, spread throughout the body, and that affects many cells and tissues in different ways
local mediators
communication molecules that function in the immediate area around the cell from which they were released
neurotransmitters
communication molecules that travel over very short intercellular gaps
hormones
communication molecules that travel throughout the organism via the blood stream
posterior pituitary
composed of support tissue for nerve ending extending formt he hypothalamus
impaired glucose tolerance
condition where a fasting blood glucose level is higher than normal but not high enough to be classifed as diabetes mellitus; "prediabetes", 141-199
Proteins containing nonproteinaceous components are called _____
conjugated proteins
What do desmosomes do?
connects two cells together by linking their cytoskeleton. They are organized for mechanical strength, not an impermeable barrier.
glycogenolysis is? Takes place in?
conversion of glycogen to glucose when blood sugar is low; glucose is returned to the blood; liver
Describe the process of glycolysis (what it is, what occurs, what is used, and what is produced)
convert glucose (6 carbons) to 2 molecules of pyruvate (3 carbons). Location: cytosol. 2 net ATP made for every glucose (2 input ATP, 4 output ATP). 2 NADH made for every glucose. .Glycolysis is inhibited by ATP.
What 5 forces create the tertiary structure?
covalent disulfide bonds between two cysteine amino acids electrostatic interactions between acidic and basic side chains hydrogen bonds van der Waals forces hydrophobic side chains pushed away from water
retina
covers the inside of the back of the eye; contains rods and cones
lipogenesis
creation of fats which move out of bloodstream to store in adipose tissue
The folds of the inner membrane of the mitochondria make up the _______.
cristae
vaccine
either an injection of antibodies or an injection of a nonpathogenic virus with the same capsid or envelope
Do fungi reproduce sexually or asexually?
either or
Salt or change in pH is a denaturing agent that disrupts what force?
electrostatic bonds
reverse transcriptase
enzyme that transcribes DNA from RNA
What is the Induced Fit Model?
flexible active site. Substrate fits inside the flexible active site, which is then induced to "grasp" the substrate in a better fit.
Fill in the blanks: For most eukaryotes, the nuclear membrane breaks down______(when?), and reforms ___(when?)
for most eukaryotes, the nuclear membrane breaks down at the beginning of mitosis, and reforms at the end of mitosis around each of the two newly formed nuclei.
tight junctions
form a watertight seal from cell to cell that can block water, ions, and other molecules from moving around and past cells
extracellular matrix
formed around cells; produced by the cells; may provide structural support, help to determine shape and motility, and affect cell growth
If an already mutated organism is mutated again, the mutations can be either _____ or ______ mutations.
forward or backward
insulitis
found in recent onset of type I diabetes caused by lymphocyte infiltration of islets; caused by aberrant expression of class II MHC molecules on the surface of beta cells
epithelial, muscle, connective, nervous
four different types of tissue in animals
A continuous supply of glucose is essential for the brain, which cannot oxidise
free fatty acids and relies upon glucose as its principal metabolic fuel
Polyuria
frequent urination
In al cells except enterocytes and the cells of the renal tubule, glucose is transported ...
from high conc. to low conc. via facilitated diffusion.
What does it mean that replication is bidirectional?
from the origin, two replisomes proceed in opposite directions along the chromosome making replication bidirectional.
chemical concentration gradient
gradual change in concentration of a compound over a distance
inclusion bodies
granules of organic or inorganic matter that may be visible under a light microscope; may or may not be bound by a single layer membrane
Euk DNA contains ___
introns, bacteria have no mechanism for removing introns
Mesosome
invaginations of the plasma membrane
Is cardiac muscle involuntary or voluntary?
involuntary
spirochetes
not rigid helically shaped bacteria
What is the nuclear envelope?
nuclear envelope is a double membrane system made of an outer and an inner membrane. Also called nuclear membrane.
What does the force of a contracting muscle depend on?
number and size of the active motor units, and the frequency of action potentials in each neuron of the motor unit.
Bacterial tRNA and rRNA go through
post transcriptional processing.
parasympathetic ANS
"rest and digest" responses; slows the heart rate and increases digestive and excretory activity
There are 4 main ways prokaryotes exhibit genetic adaptability. Explain them
*Mutation* *Transformation*: bacteria take in plasmids and DNA fragments and integrates them into the genome. *Transduction*: bacteriophages undergoing lysogenic life cycle incorporate the viral DNA into the bacterial genome. *Conjugation*: Bacteria transfer DNA between one another through the sex pilus.
Describe Prophase:
- Characterized by the condensation of chromatin into chromosomes. - Centrioles move to opposite ends of the cell; Centrioles are involved in the organization of the mitotic spindle and in the completion of cytokinesis. - Fist the nucleolus then the nucleus disappear - the spindle apparatus begins to form, projecting from the centrioles, consisting of aster(mts radiating from the centre). - the microtubules from the spindle apparatus connect to the kinetochore on each chromosome. - the kinetochore is a structure of DNA and protein located at the centromere of the joined chromatids of each chromosome.
What are the Haversian Canals?
- Haversian canals are the tunnels in compact bone created by the burrowing of osteoclasts. - Haversian Canals contain blood and lymph vessels, and are connected by crossing canals called Volkmann's canals.
What does the tertiary enzyme structure involve?
-R group interactions and spatial arrangement of secondary structure.
MITOSIS OR MEIOSIS:
...
Around what percentage of enzymes get used up in a reaction?
0. They don't get used up in a reaction.
How many oocytes/ovums (gametes) are formed from a single oogonium?
1
What are the 3 components that blood is separated into via a centrifuge?
1. Plasma, 55% 2. Buffy coat (white blood cells/leukocytes and platelets), <1% 3. Red blood cells or hematocrit, 45%
What are the 4 possible functions of muscle contraction?
1. body movement 2. stabilization of body position 3. movement of substance through body(lymphatic and cardiovascular systems) 4. generating heat to maintain body temperature
How long does the primary immune response need in order to reach its full potential?
20 days
What subunits are prokaryotic ribosomes made from?
30S and 50S subunits with a combine sedimentation coefficient of 70S
How many total ATP have been made after glycolysis and krebs cycle?
36
What subunits are Eukaryotic ribosomes made from?
40S and 60S subunits with a combined sedimentation coefficient of 80S.
The fluid inside the duodenum has a pH of ___. Due mainly to?
6; bicarbonate ion secreted by pancreas
What is the average number of exons per gene?
7
What is it called when a bp substitution or an insertion or deletion creates a stop codon?
A nonsense mutation, which are serious for the cell because they prevent the translation of a functional protein entirely.
A single ____ is specific for a single antigen, and a single B lymphocyte produces only one type of _____.
A single antibody is specific for a single antigen, and a single B lymphocyte produces only one type of antibody
The Krebs Cycle is inhibited by what?
ATP and NADH
What is the portion of an antigen that binds to an antibody called?
Antigenic Determinant:
Who can a person with type AB blood receive blood from?
Anyone; they are the universal recipient
Oxygenated blood leaves the heart via the ____.
Aorta
What is the mitotic anaphase?
Apart (Sister chromatids pulled apart to opposite sides of cell)
What is the Chlorine Shift?
As bicarbonate ion diffuses into the RBC in the capillaries of the lungs, Cl⁻ ions diffuse out of the erythrocyte in order to balance the electrostatic forces. - This is the process of the Bohr Effect wherein H₂O and CO₂ are produced and released from the cell to be exhaled by the lungs
What do Lymphoid stem cells mature into?
B and T cells/lymphocytes
What is the function of Calsequestrin and where is it found?
Calsequestrin is found in the lumen of the sarcoplasmic reticulum, and it binds Ca²⁺ ions in order to lower the free calcium ion concentration inside the lumen of the sarcoplasmic reticulum.
What are the identification techniques to finding an autosomal recessive inheritance pattern?
Can skip generations Number of affected males usual equals number of affected females
______ are microscopic blood vessels usually only one cell thick. They are the site of nutrient and gas exchange. They have no smooth muscle.
Capillaries
Minus-strand RNA
Complement to mRNA and must be transcribed to plus-RNA before being translated
What is polygenism?
Complex traits that are influenced by many different genes
What surround its myofibril and for which purpose?
Each myofibril is surrounded by the specialized endoplasmic reticulum of the muscle cell called the sarcoplasmic reticulum: - the lumen of the sarcoplasmic reticulum is filled with Ca²⁺ ions -is smooth ER found in smooth and striated muscle. The only structural difference between this organelle and the smooth ER is the medley of proteins they have, both bound to their membranes and drifting within the confines of their lumens. This fundamental difference is indicative of their functions: The ER synthesizes molecules, while the SR stores and pumps calcium ions. The SR contains large stores of calcium, which it sequesters and then releases when the muscle cell is stimulated.[11] It plays a major role in excitation-contraction coupling.
What are the regulatory proteins used by Euks and why are they better than activators or repressors?
Enhancers can act at great distances from the promoter
What role do Eosinophils play?
Eosinophils work mainly against parasitic infections
What is substrate-level phosphorylation?
Formation of ATP from ADP and inorganic phosphate using the energy released from the decay of high energy phosphorylated compounds as opposed to energy from diffusion
A mutation to an already mutated organism that changes the organism even more from its original state.
Forward mutation
What is pleiotropism?
If the alteration of a gene alters many different, seemingly unrelated aspects of the organism's total phenotype
Upon contraction, the smooth muscle cell shrinks ____-wise.
Length-wise
In what form is most of the calcium in the body stored?
Most of the Ca²⁺ is stored in the bone matrix as Hydroxyapatite.
Is skeletal muscle nucleated?
Multinucleted
What are the coenzymes involved with Krebs cycle?
NADH, FADH2
What are the Agranular Lymphocytes?
NK cells, B-Lymphocytes, T-Lymphocytes + the monocytes
How is oxygen transported through out the body?
Oxygen is transported through out the body, from the lungs to the peripheral tissue via hemoglobin.
_____ is formed when oxygen binds to the hemoglobin protein inside the erythrocytes.
Oxyhemoglobin
The most important RNA enzyme in your body is what?
Ribosome
Why are Slow twitch type I muscle fibres red?
Slow twitch type I muscle fibres are red from large amounts of myoglobin. - myoglobin is an oxygen storing protein similar to hemoglobin, but having only one protein subunit. - myoglobin stores oxygen in muscle cells.
What do plants form from glucose?
Starch and cellulose
What strand does the sequence of the newly formed primary rna transcript match?
That of the coding or sense strand, the strand with the promoter, start codon and stop codon.
What does PCR require?
That the base sequence of flanking the ends of the DNA fragment be known, so that the complementary primers can be chosen.
What is the first time the immune system is exposed to an antigen known as?
The Primary Response
What are the 4 types of cells found in bone tissue?
The four types of cells are surrounded by an extensive matrix: 1- Osteoprogenitor cells: or osteogenic cells differentiate into osteoblasts. 2- Osteoblasts 3- Osteocytes 5- Osteoclasts
What does the cardiovascular system consist of?
The heart, blood and blood vessels.
What does Deoxy mean?
The hydroxyl group on the 2' carbon has been replaced with a hydrogen
What is the second line of defence to pathogens?
The inflammatory response
Which chambers of the heart pump oxygenated blood?
The left atrium and left ventricle
What forms the synovial capsule?
The synovial fluid is held within the synovial or articular capsule. The capsule is formed by the articular cartilage that lines the ends of both bones in the synovial joint.
What is the treatment in the case where a mother's Rh+ antibodies are attacking the Rh+ blood of the fetus?
The treatment is complete replacement of the fetal blood with Rh-negative blood for the first few weeks of life. It can also be prevented if the Rh- mother is injected with anti-Rh antibodies after delivering the first Rh+ baby
Compare and contrast phospholipids and triacylglycerols.
They are both built from a glycerol backbone, but in a phospholipid, a polar phosphate group replaces one of the fatty acids
Why is a paper bag given to someone who is experiencing hyperventilation?
They are losing too much CO₂ by breathing, so blood pH is rising, creating concern for alkalosis. - the paper bag allows them to inhale CO₂ and thus lower pH of blood
In transcription regulation, what is meant by the term "transcription factors" ?
Transcription factors (protein) bind to enhancers or silencers (DNA) to affect transcription. Enhancers increase transcription when bound, while silencers decrease it.
Which technique detects proteins using antibodies?
Western Blot
Is bone a living tissue?
Yes, bone is a living tissue.
mineral corticoids
affect the electrolyte balance in the blood stream
Who can an individual with Type O blood donate to?
anyone; they are the universal donor
Why are pancreatic enzymes secreted as zymogens?
b/c pancreatic cells are not as easily replaced as intestinal epithelium
central nervous system
brain and spinal cord
tubulin
comprises microtubules
dynein
cross bridges in axoneme are made of ___
Which amino acid forms disulfide bonds?
cysteine
action potential
disturbance in the electric field across the membrane of a neuron
Mercaptoethanol is a denaturing agent that disrupts what force?
disulfide bonds
What separates epithelial tissue from connective tissue?
epithelial tissue lies on top of connective tissue, from which it is usually separated by a basement membrane/ basal surface.
bitter, sour, salty, sweet
four primary taste sensations
*The amount of filtration if related to?
hydrostatic pressure of glomerulus.
Pepsinogen is activated to pepsin by
low pH in the stomach
What is back cross?
mating between the offspring and the parent = preserve parental genotype.
virion
mature virus outside the host cell
What is the function of the mitochondria
metabolism/production of ATP
What is the function of the peroxisomes
metabolize lipids and toxins using H2O2
MITOSIS OR MEIOSIS: daughter cells identical to parent cell
mitosis
motor neurons, efferent neurons
neurons that carry signals to a muscle or gland called the effector
sensory neurons, afferent neurons
neurons that receive signal from a receptor cell that interacts with its environment and transfers the signal to other neurons (2 terms)
interneurons
neurons that transfer signals from neuron to neuron; 90% of neurons
acetylcholine
neurotransmitter used by postganglionic neurons in the parasympathetic system
acetylcholine
neurotransmitter used by preganglionic neurons in the ANS
What are the granulocytes?
neutrophils, eosinophils, basophils
Is smooth muscle striated?
no
phototrophs
organisms that use light as their energy soruce
chemotrophs
organisms that use oxidation of organic or inorganic matter
Adrenal cortex
outside portion of the adrenal glands (located on top to fhte kidneys) secretes only steroid hormones
What is produces by Krebs cycle?
oxaloacetic acid
What is the last electron acceptor in the electron transport chain?
oxygen
What are the two hardy weinberg equations?
p+q = 1 (p+q)^2 = 1 → p^2 + 2pq + q^2 = 1
The most classic example of the tumor suppressor is _____
p53
Pepsin has an optimal pH of? What happens to the pH in the small intestines?
pH of 2 in stomach; when it reaches the small intestine the pH raises to 6 which denatures pepsin.
latent period
period from infection to lysis
Antibodies are made by ____.
plasma cells (NOT LIVER)
electrical gradient
points in the direction that a positively charged particle will tend to move; for molecules with a charge
What is the large subunit of a ribosome composed of?
rRNA and protein
What do stop codons do?
signal an end to protein synthesis
glial cells
support cells in the nervous system
catecholamines
tyrosine derivatives synthesized in the adrenal medulla water soluble act mainly through cAMP messenger
What is an allele?
A variant of a gene
What vitamins does the liver store? What else does it store?
A, D, B12; iron
Describe the path air takes from the mouth/nose:
Into the mouth or nasal passages→through the throat /pharynx→passed the epiglottis→into trachea→into left and right bronchi→bronchioles→alveoli
Since blood volume flow rate is approximately constant, the blood velocity is _____ proportional to the cross-sectional area. Explain:
Inversely proportional: - The greater the cross sectional area, the slower the velocity of the blood. - Thus, since capillaries have the greatest cross sectional area, blood velocity is slowest through capillaries.
Is smooth muscle involuntary or voluntary?
Involuntary
Several _____ are wrapped by a sarcolemma (plasma membrane) to form a muscle cell/muscle fiber.
Myofibrils
What appears on the scene after macrophages in order to attack the infectious agents?
Neutrophils appear after the macrophages - most neutrophils are stored in the bone marrow until they are needed, but some are found circulating in the blood or in the tissues. - neutrophils move toward the infected or injured area, drawn in by chemicals released from damaged tissues or by the infectious agents themselves... called chemotaxis
What effect does Nitrogen have on the body?
Nitrogen is very stable due to its triple bond. - it diffuses into the blood but does NOT react with the chemicals in the blood.
Describe the pressures that exist through out the capillary bed, between the arterioles and the venules:
Osmotic pressure is constant through out the capillary bed. It remains the same from the arteriole end all the way to the venule end of the capillary. - Hydrostatic pressure is greatest at the arteriole end of the capillary and decreases towards the venule end. - Thus, there is greater fluid flow out of the capillary near the arteriole end compared to the smaller fluid flow into the capillary near the venule end. The net fluid flow into the capillary near the venule end is due to the osmotic pressure (constant) being greater than the decreased hydrostatic pressure at this point. This creates the 10% fluid loss into the interstitium, which then travels into the lymphatic system. - thus, net flow out of capillaries is greater than net flow in by 10%
Woman who carry a certain mutation that increases their risk of breast cancer display variable rates of breast cancer, depending on their diet, if they smoke, if they have had children, etx. What is this an example of?
Penetrance
Each myofibril is also surrounded by a specialized endoplasmic reticulum called the ____ _____, the lumen of which is is filled with Ca²⁺ that stimulates muscle contraction.
Sarcoplasmic reticulum
juxtaglomerular apparatus
Specialized cells next to the glomerulus that help to regulate blood pressure
*Where does protein digestion begin?
Stomach
Where are Sudoriferous glands found and what are they?
Sudoriferous glands are sweat glands and they are found in the skin separate from hair follicles.
____ T cells play a negative feedback role in the immune system.
Suppressor T cells
What coats each alveolus and what is its purpose?
Surfactant coats each alveolus and it lowers the surface tension of the alveoli in order to facilitate gas exchange across the membrane
Which nervous system innervates the smooth muscle wrapping arteries?
Sympathetic Nervous System
Blood pressure varies between ____ and ____ pressures for each heartbeat.
Systolic and diastolic
What are Telomeres?
Telomeres are repeated 6 nucleotide units from 100 to 1000 units long that protect the chromosome from being eroded through repeated rounds of replication. These are found at the ends of euk chromosomal DNA. Telomerasecatalyzes the lengthening of telomeres
_____ connect muscle to bone
Tendons
Tendons connect ____ to _____?
Tendons connect muscle to bone.
What happens to mRNA at the 5' and 3' ends during trc and what do these modifications do?
The 5' end is capped with a methyl guanine cap and this serves as protection against degradation by exonuclease. The 3' end is polyadenylated with a poly A tail, also to protect from exonuclease
Describe the Action Potential of Cardiac muscle:
The AP of cardiac muscle exhibits a plateau after depolarization. The plateau is created by slow voltage-gated calcium channels which allow calcium to enter and hold the inside of the membrane at a positive potential difference. -- the plateau lengthens the time of contraction
What happens if a B lymphocyte is able to match its antibody with the antigenic determinant on a macrophage?
The B lymphocyte, with help from the Helper T cells, differentiates into plasma cells and memory B cells. - the plasma cells then begin to synthesize free antibodies and release them into the blood.
What is the shift due to pH called?
The Bohr shift
How are blood types an example of co-dominance?
Type A cells have A antigens. Type B cells have B antigens. Type AB makes both antigens
What are the 3 stop/termination codons?
UAA, UAG, UGA
What triggers the start of Mitosis from G₂ phase?
When levels of MPF are high enough
cannot
a single synapse ___ change from inhibitory to excitatory
When do homologous chromosomes separate? When do sister chromatids separate?
anaphase I anaphase II
Negatively charged DNA fragments move towards the _____ during electrophoresis?
anode
9+2
arrangement of microtubules in the axoneme of flagella and cilia
fluid mosaic model
asymmetrical layout of its proteins; fluidity - since the forces holding the entire membrane together are intermolecular - fluid Eukaryotes - cholesterol moderates membrane fluidity
Enzyme-substrate interactions occur where?
at the enzyme's active site
hypothalamus
autonomic pathways are controlled mainly by the __ in the brain
Another name for metabolism is____
cellular respiration
What is the function of the nucleus?
compartmentalization: nuclear membrane / nuclear envelope surrounds the nucleus. genetic information is stored inside the nucleus as DNA.
axoneme
component of flagella and cilia that contains nine pairs of microtubules forming a circle around two lone microtubules in an arrangement known as 9+2; microtubules are linked by dynein cross bridges
microtubules
component of flagella, cilia, and the spindle apparatus
provirus
dormant or latent virus that is incorporated into host DNA
selectively permeable membrane
facilitated diffusion is said to make the membrane selectively permeable because it is able to select between molecules of similar size and charge
At the end of the distal tubule, ADH acts to
increase the permeability of the cells to water. Therefore, in the presence of ADH, water flows form the tubule, concentrating the filtrate
*The loop of Henle functions to?
increase the solute concentration, and thus the osmotic pressure, of the medulla
The most likely function of the brush border in the proximal convoluted tubule is to:
increase the surface area available for absorption
Aldosterone
increases reabsorption of sodium by kidney tubules
What is cytoplasmic inheritance?
inheritance of things other than genomic DNA.
hormones
molecules used for communication by the endocrine system
What is a mass of hyphae called?
mycelium
Both pyruvate and NADH pass via facilitated diffusion through a large membrane protein called ____
porin
fatty acids
simple forms of fat that supply energy fuel for most of the body's cells., building blocks of lipids, Monomer of lipids
Is cardiac muscle nucleated?
single nucleus
Is smooth muscle nucleated?
single nucleus
What does tRNA do?
tRNA collects amino acids in the cytosol, and transfers them to the ribosomes for incorporation into a protein.
________ are a 6th class of lipids which include vitamin A.
terpenes
What is the tertiary enzyme structure?
the 3-D structure
Chylomicrons
the class of lipoproteins that transport lipids from the intestinal cells to the rest of the body
On which strand is the promoter?
the coding stand, read by the RNA poly in the 5'-3' direction, while RNA ploy creates the template strand in the 3'-5' direction
In genetics, what is penetrance?
the frequency that a genotype will result in the phenotype.
somatic nervous system, autonomic nervous system
two divisions of the PNS
microglia
type of glial cell that arises from white blood cells called monocytes; they phagocytize microbes and cellular debris in the central nervous system
oligodendrocytes
type of glial cells that wrap many times around axons in the central nervous system creating myelin sheaths
epinephrine
type: catecholamine origin: adrenal medulla function:vasoconstrictorss of internal organs but vasodilators of skeletal muscles --> consistent with the fight or flight response of the sympathetic nervous system
norepinephrine
type: catecholamine origin: adrenal medulla function:vasoconstrictorss of internal organs but vasodilators of skeletal muscles --> consistent with the fight or flight response of the sympathetic nervous system
T3 and T4 (Thyroxine)
type: lipid soluble tyrosine derivatives origin: thyroid function: increases the basal metabolic rate; secretion is regulated by TSH
FSH
type: peptide origin: anterior pituitary function: growth of follicles in female; sperm production in male
Adrenocorticotropic hormone (ACTH)
type: peptide origin: anterior pituitary function:stimulates the adrenal cortex to release glucocorticoids via secondary messenger system using cAMP Release is stimulated by stress
oxytocin
type: peptide origin: posterior pituitary function: increases uterine contractions during pregnancy and causes milk to be ejected from the breasts
*What is the MAIN function of the kidney?
HOMEOSTASIS
A cell holds how many alleles of each gene?
2, one from mommy and one from daddy
sensory receptors
receptors that transduce physical stimuli to neural signals
An individual with type O blood has 2 ____ alleles.
recessive
dorsally, ventrally
sensory neurons are located __ from the spinal cord and motor neurons are located ___
____ connect bone to bone
Ligaments
What is base pair substitution that involves the reversal of the same base-pairs called?
Transversion Mutation
Describe the white blood cells(leukocytes) and their role in the body:
- White Blood Cells/Leukocytes contain organelles - They do NOT contain Hb - they play a vital role in the immune response
dyslipidaemia
- an abnormal amount of lipids in bloodstream (increased triglycerides, increases LDL, decreased HDL) - major risk factor for atherosclerosis
What are the 2 proteins that are attached to actin thin filament?
Troponin and tropomyosin
What are the big differences between granulocytes and agranulocytes?
- Agranulocytes live much longer because they work against specific agents of infection, whereas granulocytes function non-specifically against all infective agents. Therefore, agranulocytes need to hang around in case the same infective agent returns; whereas granulocytes multiply quickly against any infection and then die once the infection is gone.
What are the important proteins contained in the blood plasma?
- Albumins: for fatty acid and steroid transport, and regulate osmotic pressure of blood - Immunoglobulins: also called antibodies - clotting factors: like fibrinogen
Describe Blood:
- Blood is a connective tissue, and like any connective tissue it contains cells and a matrix - blood protects the body from injury and foreign invaders
How do myosin and actin produce the contractile force of skeletal muscle?
- Each globular head of the myosin(thick) filament crawls along the actin (thin) filament in a 5 stage cycle: 1- Tropomyosin covers an active site on the actin preventing the myosin head from binding. The myosin head remains cocked in a high energy position with a phosphate and ADP group attached. 2- In the presence of Ca²⁺, troponin pulls the tropomyosin back from the active site of actin, exposing the active site on the actin filament, allowing the myosin globular head to bind to the actin active site. 3- The myosin head expels a phosphate and ADP and bends into a lower energy position, dragging the actin along with it. This is muscle contraction. 4- ATP attaches to the myosin head. This releases the myosin head from the active site of the actin, which is then immediately covered by a tropomyosin. 5- ATP splits to inorganic phosphate and ADP causing the myosin head to cock into the high energy position. This cycle is repeated many times to form a contraction.
Describe the red blood cells of the plasma, also known as the Hematocrit:
- Erythrocytes (red blood cells), are bags of hemoglobin. - they have no organelles - no nucleus thus do not undergo mitosis or reproduce - they are disc-shaped - main function is in O₂ and CO₂ transport
Describe the structure and composition of hemoglobin:
- Hb is composed of 4 polypeptide subunits, each with a single heme cofactor - there are 2 α-chains and 2 β-chains - the heme cofactor is an organic molecule with an atom of iron at its center - each of the 4 iron atoms in Hb can bind with one O₂ molecule - When one O₂ molecule binds with an iron atom in Hb, oxygenation of the other heme groups is accelerated... this is known as cooperative binding - similarly, release of an O₂ molecule by any of the heme groups in Hb accelerates the release of the others.
Describe what happens in Prophase 1:
- Homologous chromosomes line up along side each other, matching their genes exactly. - they may or may not exchange sequence of DNA nts in a process called crossing over. - Each duplicated chromosome in prophase 1 appears as an X, these side by side homologues exhibit a total of 4 chromatids, and are called tetrads. - The single point where two chromosomes are attached to each other while crossing over, exchanging DNA is called the chiasma.
What do osteoclasts do to the compact bone?
- In a continuous process, osteoclasts burrow tunnels, called Haversian (central) canals, through compact bone.
Describe the process by which compact bone is produced:
- In a continuous process, osteoclasts burrow tunnels, called Haversian (central) canals, through compact bone. - Then osteoblasts follow the osteoclasts, laying down a new matrix onto the tunnel walls forming concentric rings called lamellae.
Describe Telophase 1 of Meiosis:
- Nuclear membrane may or may not reform, and cytokinesis may or may not occur - In humans, the nuclear membrane does reform and cytokinesis does occur - After cytokinesis, the new cells are haploid with 23 replicated chromosomes, and are called secondary spermatocytes or secondary oocytes. - in females, one of the oocytes, called the first polar body, is much smaller and degenerates. This occurs in order to save cytoplasm, which is contributed only by the ovum. - The first polar body may or may not go through meiosis 2 producing 2 polar bodies.
Describe how the Bohr Effect plays a role in oxygen loading and unloading:
- The Bohr effect is an allosteric relationship between CO₂, H⁺, and O₂. - High concentrations of CO₂ in the periphery tissue cause the CO₂ to diffuse into the erythrocyte, i combines with H₂O to form Carbonic Acid (H₂CO₃) which is then dissociated into bicarbonate ion and H⁺. This increase in H⁺ ions creates a decrease in pH→ This causes O₂ unloading in peripheral tissue, because the H⁺ binds to hemoglobin, releasing O₂ bound by Hb to the peripheral tissue - The HbH⁺ (hemoglobin with H⁺) now created has a high affinity for CO₂, thus the HbH⁺ molecule now picks up CO₂... 20% of CO₂ is transported through blood this way - HCO⁻₃ diffuses into the blood and is transported back to lungs... this is how 80% of the CO₂ is transported. - In the lungs, a high oxygen partial pressure leads to oxygenation of Hb and release of H⁺ and CO₂ from Hb (Haldane Effect) - CO₂ is directly expelled from the erythrocyte and the H⁺ combines with HCO⁻₃ to form H₂CO₃ (carbonic acid) inside the erythrocyte.... This increases pH by lowering H⁺ ion concentration... thus, since pH is increased, Hb has higher affinity for O₂, thus there is a lot of O₂ bound to Hb - Carbonic Anhydrase catalyzes the conversion of carbonic acid (H₂CO₃) to CO₂ and H₂O, which are then exhaled by the lungs.
During muscle contraction, which bands get smaller and which do not change size?
- The H zone and I band get smaller - The A band does not change size - the I band gets smaller as the ends of the myosin filaments of adjacent sarcomeres get closer upon contraction - the H zone gets smaller as the ends of actins filaments within the same sarcomere get closer together - the A band is essentially the length of the myosin filaments from end to end within a single sarcomere, thus that length never changes, as the myosin filaments do not contract or expand.
What is the Rh factor?
- The Rh factor is a specific antigen, D antigen, present on the surface of red blood cells. - Rh factors are surface proteins on red blood cells. An individual either has, or does not have, the "Rhesus factor" on the surface of their red blood cells. This term strictly refers only to the most immunogenic D antigen of the Rh blood group system, or the Rh- blood group system. The status is usually indicated by Rh positive (Rh+ does have the D antigen) or Rh negative (Rh- does not have the D antigen) suffix to the ABO blood type. However, other antigens of this blood group system are also clinically relevant. These antigens are listed separately (see below: Rh nomenclature). In contrast to the ABO blood group, immunization against Rh can generally only occur through blood transfusion or placental exposure during pregnancy in women.
Describe the S phase:
- The cell devotes most of its energy to replicating/duplicating DNA. - Each chromosome is exactly duplicated, but the cell is still considered to have the same number of chromosomes, only now, each chromosome is made of 2 identical sister chromatids.
Describe the Oxygen Dissociation Curve:
- as O₂ pressure increases, the O₂ saturation of Hb increases sigmoidally (S-shape). - this curve of Oxyhemoglobin (HbO₂), shows the percent of hemoglobin that is bound with oxygen at various partial pressures of oxygen. - in the arteries of a normal person breathing room air, the oxygen saturation is 97%
Describe Metaphase 1 of Meiosis:
- homologues remain attached, and move to the metaphase plate. - rather than single chromosomes aligned along the plate as in mitosis, tetrads align in Meiosis
Describe the G₀ phase:
- nongrowing state - allows for differences in length of the cycle between cells of different tissues - Mature neurons and muscle cells remain in G₀ permanently
Describe Platelets and their role in the body:
- platelets are also known as thrombocytes - Platelets are involved in injury repair - they are derived from small portions of membrane-bound cytoplasm torn from megakaryocytes. - megakaryocytesis a bone marrow cell responsible for the production of blood thrombocytes (platelets), which are necessary for normal blood clotting. - no nucleus containing DNA - Platelets are a natural source of growth factors. They circulate in the blood of mammals and are involved in hemostasis, leading to the formation of blood clots. - Platelets are a natural source of growth factors. They circulate in the blood of mammals and are involved in hemostasis, leading to the formation of blood clots. - they contain actin and myosin, residuals of the golgi and the ER, mitochondria, and are capable of making prostaglandins and some important enzymes
Describe G₂ phase:
- the cell prepares to divide - organelles continue to duplicate - RNA and protein, especially for microtubules, are actively synthesized - 10-20% of cell cycle - G₂ checkpoint, at the end of G₂ checks for mitosis promoting factor (MPF) - When level of MPF is high enough, mitosis is triggered
Parietal cells are found? Function? Net result?
-Exocrine glands of stomach -secrete HCl -Net result is to lower the pH of the stomach and raise the pH of the blood
What is the purpose of the mucous cells?
-Lubricates the stomach wall so that food can slide along its surface without causing damage -Mucus protects the epithelial lining from the acidic environment of the stomach -Some secrete small amounts of pepsinogen
What is produced during telophase 2 of meiosis for a female?
1 gamete and 1 polar body
What is the total ATP production of the ETC?
1 molecule of NADH produces 2-3 ATPs, while FADH2 produces only 2
What are the 2 types of Point Mutations?
1) Base-Pair substitution Mutation: results when one bp is replaced by another 2) Insertion or Deletion of a base pair, may result in a frameshift mutation. The frameshift occurs when insertions or deletions occur in multiples of 3. If the nts are randomly inserted and the downstream sequence is not affected, this is called a nonframeshift mutation
What does it mean that the genetic code is 1) Degenerative 2) Unambiguous 3) Universal?
1) Degenerative in the sense that more than one series of 3 NTs may code for any amino acid 2) Unambiguous in the sense that any single series of 3 NTs will code for one and only one amino acid. 3) Universal in the sense that nearly every living organisms uses the same code.
What are the 4 stages of the life cycle of a somatic cell of a multicellular organism?
1) G₁= The first growth phase 2) S= Synthesis 3) G₂= The second growth phase 4) M= Mitosis or Meiosis Cytokinesis (C) is the final step
What are the 5 steps of DNA replication?
1) Helicase unzips the double helix 2) RNA poly builds primer 3) DNA poly assembles leading and lagging strands 4) primers are removed 5) okazaki fragments joined
What are the 3 stages of transcription?
1) Initiation: a group of proteins called initiation factors finds a promoter on the DNA strand, and assembles a transcription initiation complex, which includes RNA polymerase. Euks have 3 types of RNA poly 2) Elongation 3) Termination
Lysogenic cycle steps (10)
1) Virus adsorbs to cell wall 2) Viral nucleic acid injected into cell 3) Reduction to provirus 4) Viral DNA integrated into chromosome 5) Reproduction of lysogenic bacteria 6) Induction of provirus to active virus (due to some external stress) 7) Replication of active virus 8) Assembly of new viruses 9) Lysis of cell 10) Virions
Lytic infection steps (6)
1) Virus adsorbs to cell wall 2) Viral nucleic acid injected into cell 3) Replication of active virus 4) Assembly of new viruses 5) Lysis of cell 6) Virions
What are the 3 ways in which the primary mRAN transcript is processed?
1) addition of NTs 2) deletion of NTs 3) modification of nitrogenous bases
Why are viruses not classified as living organisms? (5 reasons)
1) always require the host cell's reproductive machinery to reproduce 2) do not metabolize organic nutrients; use ATP made available by host cell 3) in their active form, viruses are not separated from their external environment from some type of barrier (ex. cell wall or membrane) 4) all living organisms possess both DNA and RNA; Viruses posses either DNA or RNA, but never both 5) viruses can be crystallized without losing their ability to infect
How does the human body fight viral infections?
1) antibodies - bind to viral protein 2) cytotoxic T cells - destroy infected cells
What are the 3 differences between RNA and DNA?
1) carbon number 2 on the on the pentose in RNA is not deoxygenated, it has a hydroxyl group on it. 2) RNA is single stranded 3) RNA contains pyrimidine Uracil instead of thymine
All organisms acquire energy from one of these two sources
1) light; or 2) oxidation of organic or inorganic mattter
phospholipid composition
1) phosphate group 2) 2 phatty acid chains 3) glycerol backbone
What are the 3 functions of the kidney?
1) to excrete waste products, such as urea, uric acid, ammonia, and phosphate 2) maintain homeostasis of the body fluid volume and solute composition and; 3) help control plasma pH
What are the 4 major cell types of the Epidermis?
1- 90% of the epidermis is composed of keritinocytes, which produces keratin, which helps waterproof the skin. 2- Melanocytes: transfer the melanin to keratinocytes 3- Langerhans cells interact with the helper T-cells of the immune system 4- Merkel cells attach to sensory neurons and function in the sensation of touch
Describe the process of skeletal muscle contractions:
1- An action potential originating in the CNS reaches an alpha motor neuron, which then transmits an action potential down its own axon. 2- The action potential propagates by activating voltage-gated sodium channels along the axon toward the neuromuscular junction. When it reaches the junction, it causes a calcium ion influx through voltage-gated calcium channels. 3- The Ca2+ influx causes vesicles containing the neurotransmitter acetylcholine to fuse with the plasma membrane, releasing acetylcholine out into the extracellular space between the motor neuron terminal and the neuromuscular junction of the skeletal muscle fiber. 4- The acetylcholine diffuses across the synapse and binds to and activates nicotinic acetylcholine receptors on the neuromuscular junction. Activation of the nicotinic receptor opens its intrinsic sodium/potassium channel, causing sodium to rush in and potassium to trickle out. Because the channel is more permeable to sodium, the charge difference between internal and external surfaces of the muscle fiber membrane becomes less negative, triggering an action potential. 5- The action potential spreads through the muscle fiber's network of T-tubules, depolarizing the inner portion of the muscle fiber. 6- The depolarization activates L-type voltage-dependent calcium channels (dihydropyridine receptors) in the T tubule membrane, which are in close proximity to calcium-release channels (ryanodine receptors) in the adjacent sarcoplasmic reticulum. 7- Activated voltage-gated calcium channels physically interact with calcium-release channels to activate them, causing the sarcoplasmic reticulum to release calcium. 8- The calcium binds to the troponin C present on the actin-containing thin filaments of the myofibrils. The troponin then allosterically modulates the tropomyosin. Under normal circumstances, the tropomyosin sterically obstructs binding sites for myosin on the thin filament; once calcium binds to the troponin C and causes an allosteric change in the troponin protein, troponin T allows tropomyosin to move, unblocking the binding sites. 9- Myosin (which has ADP and inorganic phosphate bound to its nucleotide binding pocket and is in a ready state) binds to the newly uncovered binding sites on the thin filament (binding to the thin filament is very tightly coupled to the release of inorganic phosphate). Myosin is now bound to actin in the strong binding state. The release of ADP and inorganic phosphate are tightly coupled to the power stroke (actin acts as a cofactor in the release of inorganic phosphate, expediting the release). This will pull the Z-bands towards each other, thus shortening the sarcomere and the I-band. 10- ATP binds to myosin, allowing it to release actin and be in the weak binding state (a lack of ATP makes this step impossible, resulting in the rigor state characteristic of rigor mortis). The myosin then hydrolyzes the ATP and uses the energy to move into the "cocked back" conformation. In general, evidence (predicted and in vivo) indicates that each skeletal muscle myosin head moves 10-12 nm each power stroke, however there is also evidence (in vitro) of variations (smaller and larger) that appear specific to the myosin isoform. 11- Steps 9 and 10 repeat as long as ATP is available and calcium is present on thin filament. 12- While the above steps are occurring, calcium is actively pumped back into the sarcoplasmic reticulum. When calcium is no longer present on the thin filament, the tropomyosin changes conformation back to its previous state so as to block the binding sites again. The myosin ceases binding to the thin filament, and the contractions cease. - The calcium ions leave the troponin molecule in order to maintain the calcium ion concentration in the sarcoplasm. The active pumping of calcium ions into the sarcoplasmic reticulum creates a deficiency in the fluid around the myofibrils. This causes the removal of calcium ions from the troponin. Thus, the tropomyosin-troponin complex again covers the binding sites on the actin filaments and contraction ceases.
What are the two hormones that determine the continual process of bone remodification via the osteoclasts and osteoblasts?
1- Calcitonin decreases osteoclast activity, thus decreases blood calcium levels by keeping more bone intact. 2- Parathyroid hormone increases osteoclast activity, thereby increasing blood calcium levels by increasing bone tissue breakdown.
What are the 3 types of joints?
1- Fibrous Joints 2- Cartilaginous Joints 3- Synovial Joints
List and describe the 3 types of cartilage:
1- Hyaline: also called articular, is the most common. It is found in joints, on the ends of bones and it reduces friction and absorbs shock in joints 2- Fibrocartilage 3- Elastic
What are the 3 specialized cells of the Epidermis?
1- Keratinocytes 2- Melanocytes 3- Dendritic cells that are phagocytes that eat pathogens and activate the immune response.
What are the four types of bones?
1- Long 2- Short 3- Flat 4- Irregular
What are the 3 types of skeletal muscle fibres?
1- Slow oxidative (type I): Slow Twitch 2- Fast oxidative (type II A): Fast Twitch A 3- Fast glycolytic (type II B): Fast Twitch B
What are the 2 principal parts of the skin?
1- The Epidermis 2- The Dermis
What are the important functions of the skin?
1- Thermoregulation 2- Protection: produces melanin which protects against UV radiation. 3- Environmental Sensory Input 4- Excretion 5- Immunity 6- Blood reservoir 7- Vitamin D synthesis 8- Water Homeostasis
Describe the 5 stage cycle of a single myosin head acting with a single actin molecule/polymer:
1- Tropomyosin covers the active site on actin, which prevents the myosin head from binding to actin. During this time, the myosin head is in a high energy, cocked state as it possesses a phosphate and ADP group. 2- After a signal for muscle contraction, Ca²⁺ ions are released from the sarcoplasmic reticulum and bind to the troponin molecule, which causes tropomyosin to pull away from the active site of actin. This frees up the myosin binding site so that the myosin head can bind to actin.. forming the cross-bridge. 3- The myosin head releases phosphate and ADP and bends into a low energy position, thus dragging the actin filament along with it. The bending of the myosin filament is what causes the contraction. 4- ATP attaches to the myosin head, releasing it from the active site of actin (Ca²⁺ dissociates from troponin, allowing for tropomyosin to again cover the actin active site) 5- ATP hydrolyzes to ADP+Pi and the myosin head goes back to its cocked, high-energy position.
What are the 3 steps by which coagulation occurs?
1. A dozen or so coagulation factors form a complex called Protrombin Activator... this is initiated by platelets adhering to collagen fibres in the connective tissue and releasing substances to make nearby platelets sticky. This forms a plug that provides immediate emergency protection against blood loss. 2. Protrombin activator catalyzes the conversion of prothrombin, a plasma protein, into thrombin 3. Thrombin is an enzyme that governs the polymerization of the plasma protein fibrinogen to fibrin threads that attach to the platelets and form the tight plug. This reinforces the original loose plug created by the platelets. - fibrin is eventually degraded by plasmin to conclude the healing process - this blood clot formation or coagulation begin to appear in seconds in small injuries and 1 to 2 minutes in larger injuries
What are the 3 categories by which Leukocytes can be subdivided into?
1. Agranular Monocytes 2. Granulocytes 3. Agranulocytes
List the pathway of gas exchange in humans:
1. Air enters the external nares (nostrils) and travels through the nasal passage where it is filtered by nasal hairs and mucous (air also enters through the mouth) 2. Air passes through the pharynx and into the larynx (voice box). to ensure food does not enter the respiratory tract on route to the esophagus, the epiglottis covers the glottis (opening to the larynx). 3. Air passes from the larynx into the cartilaginous trachea 4. Air passes into two bronchi, left and right, which enter the lungs. 5. Bronchi further divide into bronchioles 6. Each bronchiole is surrounded by clusters of small air sacs called alveoli- this is where gas exchange occurs 7. Each alveolus is coated by surfactant which lowers the surface tension of the alveoli and facilitates gas exchange across the membrane 8. Alveoli increase the overall surface area available for gas exchange (O₂ and CO₂) with the pulmonary capillary beds.
What other factors does oxygen saturation depend on?
1. Carbon Dioxide pressure 2. pH 3. Temperature
What are the scenarios in which the oxygen dissociation curve shifts to the left, thereby indicating an increasing of Hemoglobin's affinity for oxygen?
1. Decreased pressure of CO₂ 2. Decreasing temperature 3. Decreasing [H⁺], or increasing pH
What are the 4 aspects of inflammatory response?
1. Dilation of blood vessels 2. Increased permeability of capillaries 3. Swelling of tissue cells 4. Migration of macrophages and granulocytes to the inflamed area where they remove pathogens through phagocytosis.
The main things to remember from the Bohr Effect:
1. High H⁺ concentration in the periphery cause the unloading of O₂ from Hb into the tissue 2. Low H⁺ concentration in the lungs cause the Loading of O₂ into Hb.
What are the 2 types of acquired immunity?
1. Humoral or B-cell immunity 2. Cell-mediated or T-cell immunity
What are the 3 forms in which carbon dioxide is carried by the blood?
1. In physical solution 2. as bicarbonate ion: 10 times as much than any other form 3. in carbamino compounds (combined with hemoglobin and other proteins)
What are the scenarios in which the oxygen dissociation curve shifts to the right, thereby indicating a lowering of Hemoglobin's affinity for oxygen?
1. Increased pressure of CO₂ 2. Increasing temperatures 3. Decreasing pH/Increasing [H⁺] 4. 2,3-BPG
What are the 2 components of the human immune system?
1. Innate Immunity: generalized protection from most invading organisms and toxins 2. Acquired Immunity: protection against specific organisms or toxins, which develops after the body has been first attacked. Includes antibodies and lymphokines
What are the 5 steps to solving a pedigree problem?
1. Is the allele dominant or recessive (is it in every generation or does it skip one 2. Is it sex-linked or autosomal. Sex linked usually affects males more, and autosomal affects them equally 3. If it is sex-linked, is it on the X or Y chromosome? Y chromosome will show father-to-son transmission, X chromosome will not 4. Check for mitochondrial inheritance 5. Figure out the genotypes and calculate probabilities. For sex-linked traits, include the chromosomes, but for autosomal traits, do not.
What are the multiple interrelated functions of the lymphatic system?
1. It is responsible for the removal of interstitial fluid from tissues 2. It absorbs and transports fatty acids (chylomicrons) to the circulatory system 3. It transports immune cells throughout the body
What is the process of response from the innate immunity?
1. Macrophages phagocytize 2. Neutrophils phagocytize 3. Eosinophils work against parasitic invasion 4. Basophils release histamine for the inflammatory response 5. Natural Killer cells 6. Mast Cells
What are the 4 ways material can cross capillary walls?
1. Pinocytosis: In cellular biology, pinocytosis ("cell-drinking", "bulk-phase pinocytosis", "non-specific, non-absorptive pinocytosis", "fluid endocytosis") is a form of endocytosis in which small particles are brought into the cell, forming an invagination, and then suspended within small vesicles (pinocytotic vesicles) that subsequently fuse with lysosomes to hydrolyze, or to break down, the particles. 2. Diffusion or transport through capillary membranes 3. movement through fenestrations in the cells 4. movement between space between cells.
What are the 2 types of smooth muscle?
1. Single Unit 2. Multi-unit
What are the 3 types of muscle tissue?
1. Skeletal 2. Cardiac 3. Smooth
What does innate immunity include?
1. Skin as a barrier to organisms and toxins 2. stomach acid and digestive enzymes to destroy ingested organisms and toxins 3. phagocytotic cells 4. chemicals in the blood
What are the 2 ways in which fluid is propelled through the lymphatic system?
1. Smooth muscle in the walls of the larger lymph vessels contracts when stretched 2. The lymph vessels may be squeezed by adjacent skeletal muscles, body movements, arterial pulsations, and compression from objects outside the body.
What are the 3 main types of lymphocytes?
1. T cells 2. B cells 3. Natural killer cells
name the four cells of the stomach:
1. mucous cells 2. chief (peptic) cells 3. parietal (oxyntic) cells 4. G cells
By mass, Chromatin is ____ DNA, and ____ Protein.
1/3 DNA, 2/3 Protein
What does penetrance mean in terms of having 100% penetrance vs having <100% penetrance?
100% penetrance means that if you have the genes for being smart, then you'll definitely be smart! Less than 100% penetrance means that you may have the genes for being smart, but you may not actually be smart
What is a normal heartbeat for a healthy resting adult?
120mmHg systolic and 80mmHg diastolic
How are carbs broken down?
1st: salivary amylase 2nd: pancreatic amylase - degrades carbs from the chyme into small glucose polymers 3rd: brush border enzymes finish degrading polymers into monosaccharides
There are three different scenarios for double crossover. How many of them result in genetic recombination?
2
End products of glycolysis
2 ATP, 2 pyruvates, 2 NADH, 2 H+ and 2H20
Codominance. What is a major example of this
2 alleles are both expressed but not blended. ABO blood groups
How many carbons are gained/lost during krebs?
2 carbons lost (as CO2)
What is the probability of having a color blind child if the mother is a carrier and the father is normal?
50% chance of having a child who is not a carrier, 25% chance of having a girl who is a carrier, and a *25% chance of having a color blind boy*.
Veins, venules and venus sinuses in the systemic circulation contain __% of the blood by volume, while arteries, arterioles and arteries in the systemic circulation contain ___% of the blood by volume.
64%; 20%. - Thus the veins, venules and venus sinuses contain a far greater volume of blood than do arteries, arterioles and capillaries. - the veins, venules and venus sinuses act as a reservoir for blood.
The glands located deep between the villi and the intestinal exocrine glands secrete an intestinal juice with a pH of ___. They also secrete ____ which help regulate bacteria within the intestine.
7.6; Lysozymes
What are the proportions of gases that exist in the air we breathe out?
79% nitrogen 16% oxygen 5 % carbon dioxide
What are the proportions of gases that exist in the air we breathe in?
79% nitrogen 21% oxygen
__% of oxygen in the blood binds rapidly and reversibly to hemoglobin.
98%
What determines whether the growing polypeptide and the ribosome attach to the ER?
A 20 amino acid sequence called a signal peptide near the front of the polypeptide is recognized by protein-RNA signal-recognition particle (SRP) that carries the entire ribosome complex to a receptor protein on the ER.
The oxygen dissociation curve of Myoglobin exhibits what sort of graph?
A Hyperbolic Dissociation Curve
A blood donor may donate blood only to an individual that does not make ______ against the donor blood.
A blood donor may donate blood only to an individual that does not make antibodies against the donor blood. - therefore, a type A person can only donate blood to a type A person, not to a type O or type B person because both Type B and O produce antibodies against type A. In the figure (+) means it is rejected (agglutinates)
A change in enzyme structure equals what?
A change in function.
urea
A chemical that comes from the breakdown of proteins.
What do frameshift mutations result in?
A completely non-functional protein, whereas nonframeshift mutations may still result in a partially or even completely active protein.
Explain why chickens are used as an example of incomplete dominance
A cross between black chickens and white chickens give rise to bluish grey chickens.
What do single addition/insertion and deletion mutations result in?
A frameshift mutation
What's an example of epistasis
A gene for curly hair cannot be expressed if a different gene causes baldness.
cheiroarthropathy
A group of musculoskeletal conditions including frozen shoulder and carpal-tunnel syndrome,....is extremely common in people with longstanding type 1 diabetes and is an important source of functional disability in this population
What governs the process of DNA replication?
A group of proteins called a replisome. Replisone:The replisome is a complex molecular machine that carries out replication of DNA. The replisome first unwinds double stranded DNA into two single strands. For each of the resulting single strands, a new complementary sequence of DNA is synthesized. The net result is formation of two new double stranded DNA sequences that are exact copies of the original double stranded DNA sequence.
hyperglycaemia
A high blood glucose concentration.
How does a muscle contraction begin?
A muscle contraction begins with an action potential. A neuron attaches to a muscle cell forming a neuromuscular synapse. - The AP of the neuron releases acetylcholine into the synaptic cleft. - The acetylcholine activates ion channels in the sarcolemma of the muscle cell creating an AP. - the AP moves deep into the muscle cell via small tunnels in the membrane of the sarcolemma called T-tubules. - the AP is then transferred to the sarcoplasmic reticulum which then becomes more permeable to Ca²⁺ ions. - The Ca²⁺ ions begin the 5 stage cycle by stimulating troponin to pull tropomyosin away from the active site on actin, thus allowing the myosin globular head to attach to the actin active site
Describe how a muscle uses leverage to create movement:
A muscle uses leverage by applying a force to a bone at its insertion point and rotating the bone in some fashion about the joint. Most lever systems of the body act to increase the required force of a muscle contraction. In other words, a greater force than mg is required to lift a mass m. This is done in order to reduce the bulk of the body and increase the range of movement. If the muscle has a shorter lever arm it is closer to the body, and thus creates less bulk.
What is formed when the sarcomeres are laid end to end?
A myofibril: A myofibril (also known as a muscle fibril) is a basic rod-like unit of a muscle. Muscles are composed of tubular cells called myocytes, also known as muscle fibers, and these cells in turn contain many chains of myofibrils. Myofibrils are composed of long proteins such as actin, myosin, and titin, and other proteins that hold them together. These proteins are organized into thin filaments and thick filaments, which repeat along the length of the myofibril in sections called sarcomeres. Muscles contract by sliding the thin (actin) and thick (myosin) filaments along each other. Actomyosin motors are important in muscle contraction (relying in this case on "classical myosins") as well as other processes like retraction of membrane blebs, filiopod retraction, and uropodium advancement (relying in this case on "nonclassical myosins").
What happens when air enters the intrapleural space, and what would cause air to enter this space?
A penetrating injury would cause air to enter the pleural cavity. - When air enters this intrapleural space, the lung collapses because the pressure inside the intrapleural space increases. - This is called pneumothorax.
What is a primer?
A primer is a strand of nucleic acid that serves as a starting point for DNA synthesis. They are required for DNA replication because the enzymes that catalyze this process, DNA polymerases, can only add new nucleotides to an existing strand of DNA. The polymerase starts replication at the 3'-end of the primer, and copies the opposite strand. In most cases of natural DNA replication, the primer for DNA synthesis and replication is a short strand of RNA (which can be made de novo).
Describe why there exists a difference in blood flow velocity through out the body:
A single artery is much bigger than a capillary, but there are far more capillaries than arteries. The total cross-sectional area of all the capillaries put together is much greater than the cross-sectional area of a single aorta or a few arteries. - Blood flow follows the Continuity Equation: Q=AV, so velocity is greatest in the arteries where cross-sectional area is smallest and velocity is lowest where cross sectional area is greatest, as in the capillaries.
Since there is a much lower hydrostatic pressure in the veins, what prevents the back-flow of blood?
A system of valves prevents the back-flow while movement of skeletal muscle provides the force necessary to return blood to the heart. - Contraction of skeletal muscle helps move blood through veins, however, the major propulsive force moving the blood through the veins is the pumping force of the heart.
Explain how translational elongation occurs?
A tRNA with its corresponding amino acid attaches to the A site (aminoacyl site) at the expense of two GTPs. The c-terminus of methionine attaches to the N-terminus of the amino acid at the A site in a dehydration reaction catalyzed by peptidyl transferase, an activity possessed by the ribosome.
What happens to the trachea as it enters the lungs?
A the trachea approaches the lungs it splits into the left and right bronchi. - each bronchus branches many more times to become tiny bronchioles - bronchioles terminate in tiny grape-like clusters called alveolar sacs, composed of tiny alveoli.
Tracylglycerols are constructed from what? What is their function in a cell?
A three carbon backbone called Glycerol attached to three fatty acids. To store energy
lacteal
A tiny lymph vessel extending into the core of an intestinal villus. Nutrients absorbed through wall of small intestine pass into capillary network and lacteal.
What are transposons?
A transposable element (TE) is a DNA sequence that can change its relative position (self-transpose) within the genome of a single cell. The mechanism of transposition can be either "copy and paste" or "cut and paste". Transposition can create phenotypically significant mutations and alter the cell's genome size. They can contain one gene, several genes or just a control element. A transposon within a chromosome will be flanked by identical NT sequences.
A gene for a flower color has 2 alleles, R(red) and r(white): A. What is the phenotype of Rr heterozygotes B. If R and W display incomplete dominance, what is the phenotype of RW heterozygotes. C. How many phenotypes are possible if R and W display incomplete dominance?
A. red B. pink C. 3 genotypes, 3 phenotypes RR(red), RW(pink) WW(white)
What is the Genotype for each blood type?
A=II or Ii B=II or Ii AB=IaIb O=ii
Posterior pituitary hormones (peptide)
ADH and oxytocin
Nucleoid
AKA chromatin body, nuclear region, or nuclear body; not enclosed by a membrane formed by DNA, RNA,a nd protein complex in proaryotes
What is the start codon?
AUG, also codes for the amino acid methionine
*What doesn't occur in stomach?
Absorption
What NT is released from neurons to stimulate a muscle contraction?
Acetylcholine
In regards to bacteria and regulation at the transcription level, some genes are actively transcribed, while others are not. What modulates the transcription of a gene?
Activaters and inhibitors modulate the transcription of a gene.
How does adult skeletal muscle create new muscle cells if at all?
Adult skeletal muscle does not undergo mitosis to create new muscle cells (hyperplasia). - instead, a number of changes occur over time as the muscles are exposed to forceful, repetitive contractions - these changes include: the diameter of the muscle fibres increase, the number of sarcomeres and mitochondria increase, and sarcomeres lengthen. - Muscle cells are so specialized that they have lost the ability to undergo mitosis. Only in rare cases does one muscle cell split to form 2.
What are the identification techniques to finding an Y-linked inheritance pattern?
Affected father has all affected sons, and unaffected father can't have an affected son
How is myosin an ATPase?
After myosin binds to actin and pulls the actin filament along, creating the muscle contraction, ATP binds to myosin releasing it from the actin filament. - Myosin immediately hydrolyzes the ATP using the energy to return to its ready and high energy position.
After replication, _____ are attached at the centromere. During mitosis, _____are attached at the centromere and pulls the sister chromatids apart
After replication, sister chromatids are attached at the centromere. During mitosis, spindle fibers are attached at the centromere and pulls the sister chromatids apart
The ____ is the muscle that is responsible for the movement; while the ___ is the muscle is the muscle that stretches.
Agonist; antagonist
From adipose tissue, most fatty acids are transported in the form of free fatty acids which combines immediately in the blood with ____.
Albumin
Where are most of the plasma proteins formed?
Albumin, fibrinogen and most other plasma proteins are formed In the liver
What could Hyperventilation cause?
Alkalosis by increasing the blood pH too far
Where do all blood cells differentiate from?
All blood cells differentiate from the same type of precursor, a stem cell residing in the bone marrow.
Describe single unit smooth muscle:
Also called visceral, is the most common. * connected by gap junction spreading the action potential from a single neuron through a large group of cells, and allowing the cells to contract as a single unit. *found in the arteries and veins, the stomach, intestines, uterus, and urinary bladder.
Describe single unit smooth muscle:
Also called visceral, is the most common. - single unit smooth muscle cells are connected by gap junction spreading the action potential from a single neuron through a large group of cells, and allowing the cells to contract as a single unit. - single-unit smooth muscle is found in the arteries and veins, the stomach, intestines, uterus, and urinary bladder. - Basically, numerous muscle fibres are innervated by a single autonomic neuron, and so all muscle fibres innervated by the single neuron fire at the same time
What is Alternate splicing?
Alternate splicing: different ways of cutting up and RNA and rejoining the exons pieces make different final RNA products.
Mnemonic for ADH?
Always Digging Holes ADH is always digging holes in the collecting duct.
What is the by-product of gluconeogenesis from proteins?
Ammonia, a nitrogen containing cmpd
Starch comes in what two forms?
Amylose and amylopectin
What is the A Band of a sarcomere?
An A-band contains the entire length of a single thick filament (myosin). - this is the region between two Z bands
What is the entire system of Haversian canals and lamellae called?
An Osteon or Haversian System: - The osteon or Haversian system is the fundamental functional unit of compact bone. Osteons are roughly cylindrical structures that are typically several millimeters long and around 0.2mm in diameter. - Each osteon consists of concentric layers, or lamellae, of compact bone tissue that surround a central canal, the Haversian canal. The Haversian canal contains the bone's nerve and blood supplies. The boundary of an osteon is the cement line. Between adjoining osteons there are angular intervals that are occupied by interstitial lamellae. These lamellae are remnants of osteons the greater parts of which have been destroyed. Near the surface of the compact bone the lamellae are arranged parallel to the surface; these are called circumferential lamellae. Some of the osteoblasts develop into osteocytes, each living within its own small space, or lacuna. Osteocytes make contact with the cytoplasmic processes of their counterparts via a network of small transverse canals, or canaliculi. This network facilitates the exchange of nutrients and metabolic waste. Collagen fibers in a particular lamella run parallel to each other but the orientation of collagen fibers within other lamellae is oblique. The collagen fiber density is lowest at the seams between lamellae, accounting for the distinctive microscopic appearance of a transverse section of osteons. The space between osteons is occupied by interstitial lamellae, which are the remnants of osteons that were partially resorbed during the process of bone remodelling. Osteons are connected to each other and the periosteum by oblique channels called Volkmann's canals or perforating canals.
What is it called when a deletion or duplication occurs with an entire single chromosome?
Aneuploidy, - Down Syndrome is the result of aneuploidy where there are 3 copies of chromosome 21
What does all muscle contraction begin with?
An action potential which then releases acetylcholine into the synaptic cleft. - acetylcholine then activates ion channels of the motor end plate located on the sarcolemma. - this initiates a new action potential inside the muscle fibre. - this new AP moves deep into the muscle fibre via T-tubules - The AP is eventually transferred to the sarcoplasmic reticulum, which then becomes permeable to Ca²⁺ ions. - then contraction of the sarcomere units occurs - at the end of the cycle, Ca²⁺ is actively pumped back into the sarcoplasmic reticulum⁺
Micelles
An aggregate of surfactant molecules dispersed in a liquid colloid. In digestion these contain lipid droplets.
What are antibodies and what do they do?
An antibody (Ab), also known as an immunoglobulin (Ig), is a large Y-shaped protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, called an antigen. Each tip of the "Y" of an antibody contains a paratope (a structure analogous to a lock) that is specific for one particular epitope (similarly analogous to a key) on an antigen, allowing these two structures to bind together with precision. Using this binding mechanism, an antibody can tag a microbe or an infected cell for attack by other parts of the immune system, or can neutralize its target directly (for example, by blocking a part of a microbe that is essential for its invasion and survival). The production of antibodies is the main function of the humoral immune system.
What is an antigen and what does it do?
An antigen is a substance that evokes the production of one or more antibodies. Each antibody binds to a specific antigen by way of an interaction similar to the fit between a lock and a key. The substance may be from the external environment or formed within the body. The immune system will try to destroy or neutralize any antigen that is recognized as a foreign and potentially harmful invader. The term originally came from antibody generator and was a molecule that binds specifically to an antibody, but the term now also refers to any molecule or molecular fragment that can be bound by a major histocompatibility complex (MHC) and presented to a T-cell receptor. "Self" antigens are usually tolerated by the immune system, whereas "non-self" antigens can be identified as invaders and can be attacked by the immune system.
Renin
An enzyme secreted by the juxtaglomerular cells when blood pressure decreases. Renin onverts angiotensinogen to angiotensin I.
Describe zymogens (aka proenzymes)
An inactive form of an enzyme, that when specific peptide bonds on zymogens are cleaved, the zymogens become irreversibly activated
What does a shift the the left of the Oxygen Dissociation Curve indicate?
An increasing of Hemoglobin's affinity for oxygen - Left shift=more bound O₂
How does an infected cell signal for its own death?
An infected cell signals for its own death by presenting some of the antigen on its surface through the class I MHC molecule and then its destroyed by an activated cytotoxic T cell
What is non-competitive inhibition?
An inhibitor binds to an allosteric site on the enzyme to deactivate it.
What is competitive inhibition?
An inhibitor competes with the substrate for binding to the active site.
Amylose
An isomer of cellulose that may be branched or unbranched and has the same alpha linkages as glycogen
Describe the process of anaerobic fermentation
Anaerobic fermentation (cytosol) = redox reaction: reduce pyruvate, oxidize NADH. 1 NAD+ made for every pyruvate. Alcohol fermentation = pyruvate reduced to ethanol. Lactic acid fermentation = pyruvate reduced to lactate. The purpose of anaerobic fermentation is to regenerate NAD+, which is needed for glycolysis.
______ consist of gamma globulin proteins of two large heavy chains and two small light chains.
Antibodies - The constant region remains virtually unchanged - The variable region is able to recognize a specific epitope on an antigen
What are two major things that bring about apoptosis?
Apoptosis can be brought upon by development (eg tadpole losing tail) or by immune response (infected/cancerous cells killed by cytotoxic T cells/natural killer cells
____ are wrapped with smooth muscle that is typically innervated by the sympathetic nervous system.
Arteries
______ move blood away from the hear, are elastic, stretch when filled with blood, and are wrapped in smooth muscle for vasoconstriction-innervated by the sympathetic nervous system.
Arteries
_____ are elastic and stretch as they fill with blood.
Arteries: - as the ventricles finish their contraction, the stretched arteries recoil, keeping the blood moving more smoothly.
What are the main mechanism used to regulate blood pressure and reroute blood?
Arterioles
_____ are very small. They are wrapped by smooth muscle. Constriction and dilation of _____ can be used to regulate blood pressure as well as rerouting blood.
Arterioles
______ control where blood flows, are smaller arteries with more smooth muscle wrapped around them. Constriction and dilation are used to regulate blood pressure and to reroute blood flow.
Arterioles
How are detoxified chemicals excreted by the liver?
As part of pile or polarized so they may be excreted by the kidney
What happens to platelets as they come in contact with an injured endothelium?
As platelets come into contact with an injured endothelium, they become sticky and begin to swell, releasing various chemicals and activating other platelets. - the platelets then stick to the endothelium and to each other, forming a loose platelet plug...coagulation
What happens to nitrogen levels as people go scuba diving?
As pressure increases with depth, more nitrogen diffuses into the blood. - When divers come back to the surface, pressure decreases and thus the gas volume of nitrogen increases. - If they do not allow enough time for nitrogen to diffuse out of the blood and into the lungs, the nitrogen will form bubbles. - these bubbles block the vessels causing decompression sickness, also known as "the bends"
How is the Oxygen dissociation curve affected with an increase in temperature?
As temperature increases, the curve is shifted to the right, indicating a lowered affinity for O₂.
At birth, all bone marrow is ___, but with age, more of it is converted to the ____ type.
At birth, all bone marrow is red, but with age, more of it is converted to the yellow type.
What happens to endogenous levels of 2,3-BPG/DPG at higher altitudes?
At higher altitudes endogenous levels of 2,3-DPG/BPG increase to facilitate better release of oxygen within the tissues. - Thus, people who live at higher altitudes have greater amounts of it in their blood
Restriction fragments and their sticky ends are joined to others via DNA _____?
Ligase, which builds the new phosphodiester bonds.
A mutation to an already mutated organism that reverts the organism back to its original state.
Backward mutation
What types of invaders is Humoral immunity effective against?
Bacteria, Fungi, parasitic protozoans, viruses and blood toxins
What are the differences between base substitutions, invertions, and additions?
Base substitution = mutation involving a base (ATGC) changing to a different base. Inversion = a stretch of DNA (a segment of a chromosome) breaks off, then reattaches in the opposite orientation. Addition = also called insertion = an extra base is added/inserted into the DNA sequence
______ release many of the chemicals of the inflammation response.
Basophils
Enzymes do nothing for Keq. Why is this?
Because it lowers the activation energy for BOTH forward and reverse reactions
What is genetic linkage?
Because of independent assortment, genes on different chromosomes are randomized. However, genes on the same chromosome can not be randomized by this mechanism. Genes on the same chromosome are linked to some extent.
Why is the entire circulatory system said to be a closed circulatory system?
Because there are no openings for the blood to the leave the vessels.
When does replication takes place in the human female?
Before birth and the life cycle of all germ cells are arrested at the primary oocyte stage until puberty. - Just before ovulation, a primary oocyte undergoes the first meiotic division to become a secondary oocyte. - the secondary oocyte is released upon ovulation, and the penetration of the secondary oocyte by the sperm stimulates anaphase 2 of the second meiotic division in the oocyte.
What lies beneath the skin?
Beneath the skin is a subcutaneous tissue called the superficial facia or hypodermis. - the fat of this subcutaneous layer is an important heat insulator for the body. The fat helps maintain normal core body temps on cold days while the skin approaches the temp of the environment.
Fill in the blanks: Between the outer and inner membrane is the ________, which is is ____(high or low) in protons H+. The _________ separates the mitochondria from the cytoplasm
Between the outer and inner membrane is the intermembrane space. The intermembrane space is high in protons H+. The outer membrane separates the mitochondria from the cytoplasm
SInce carbonic anhydrase is inside the red blood cell and not free in the plasma, when CO₂ is absorbed in the lungs, _____ ion diffuses into the red blood cell. Why?
Bicarbonate ion diffuses into the cell in order to allow the reverse reaction of carbonic anhydrase. This creates H₂O and CO₂, wherein the CO₂ diffuses out of the cell and is exhaled out of the lungs.
During fat metaboolism, the liver synthesizes ____ from ___ and converts ____ into fat. What does it oxidize for energy and forms?
Bile from cholesterol; oxidizes fatty acids for energy, and forms most lipoproteins
Blood flows into the first capillary bed of the nephron called the ___________. Together, _________ _________ and the ___________ make lip the renal ___________
Blood flows into the first capillary bed of the nephron called the g lomerulus. Together, Bowman's capsule and the glomerulus make lip the renal corpuscle
List the circulatory pathway of blood:
Blood from body→superior and inferior vena cava→right atrium→tricuspid valve→right ventricle→pulmonary valve→pulmonary artery→lungs→pulmonary vein→left atrium→mitral valve→let ventricle→aortic valve→aorta→Blood to body
What force propels the blood through the cardiovascular system?
Blood is propelled through the system by the hydrostatic pressure created by the contraction of the heart.
Blood pressure ____ near the heart and ____ to its lowest in the capillaries.
Blood pressure increases near the heart and decreases to its lowest in the capillaries. - Blood pressure deceases from the arteries to the capillaries and then stays constant in the venules and veins.
Describe the changes in blood pressure through out the areas of the systemic circulation, starting with the Aorta:
Blood pressure is highest in the aorta and slowly decreases through the large arteries, small arteries and then plunges through the arterioles and capillaries. - Blood pressure reaches its lowest in the venules and small veins. - BP stays at its lowest through the large veins to the vena cava, then it increases a little through the pulmonary arteries, arterioles. - After the pulmonary arterioles, BP starts to decreases again into the pulmonary capillaries, venules and veins.
What are the factors that affect interstitial pressure?
Blood pressure, plasma osmotic pressure, interstitial osmotic pressure (from proteins, infection response, etc), permeability of capillaries
liver has the following interrelated functions
Blood storage Blood filtration- take out bacteria Carbohydrate metabolism Fat metabolism Protein metabolism Detoxification Erythrocyte destruction: Vitamin storage
How are blood types identified?
Blood types are identified by the A and B surface antigens. - for instance, Blood type A means that the RBC membrane has A antigens and does not have B antigens. Thus, if the erythrocyte has A antigens, the immune system does NOT make A antibodies or this would be an autoimmune disease
Blood velocity decreases going from ____ to ____ and then increases going to ___ and ___.
Blood velocity decreases going from arteries to capillaries and then increases going to venules and veins.
What are the functions of bones?
Bone functions to support soft tissue, protect internal organs, assist in movement of the body, store minerals like calcium, blood cell production, and energy storage in the form of adipose cells in the bone marrow.
Erythrocytes lose their nucleus while still in the ____ ____.
Bone marrow
Explain what causes Translocation and Inversion:
Both, Translocation and inversion occur due to Transposition. Transposition takes place in both proks and euks. The DNA segments called transposable elements or transposons can excise themselves from a chromosome and reinsert themselves at another location. When moving, the transposon may excise itself from the chromosome and move; it may copy itself and move, or copy itself and stay, moving the copy.
How is cardiac muscle shaped?
Branched
What is breathing dependent on?
Breathing is dependent on pressures changes inside the thoracic cavity (body cavity containing the lungs and heart), which is separated from the abdominal cavity via the diaphragm
How do enzymes speed up reactions?
By decreasing the activation energy by lowering the energy at the transition state.
Where are red blood cells formed?
By stem cells in the bone marrow
How does blood regulate the extracellular environment of the body?
By transporting nutrients, waste products, hormones, heat, and cells of the immune response.
(T=tall, t=short, G=green, g=yellow) The height and color genes are located near each other on the same chromosome and display complete linkage but the shape gene is located on a different chromosome. If an individual with a TtGgWw genotype and the T and g alleles on the same chromosome is crossed with a ttGgWw individual, what result will be observed? A. All tall peas will be wrinkled B. All wrinkled peas will be tall C. All yellow peas will be tall D. All tall peas will be yellow
C. All yellow peas will be tall The gene for shape is on a different chromosome, so A and B are eliminated. To be yellow, a pea must be homozygous gg. One of the g alleles must come from the chromosome with T and g together, making all yellow plants tall.
What are enzymes, and, in general, what do they do?
Catalysts, which are things that increase the rate of a reaction
If the dominant allele for curly (C) results in curly hair and the recessive allele (c) causes straight hair, what are the phenotypes of CC, Cc, and cc individuals? Also, what is this an example of?
CC and Cc individuals have curly hair, and cc have straight. Classical dominance
Why does DNA with more CG base pairs have a higher melting temp?
CG base pairs have 3 H-bonds whereas AT base pairs only have 2.
In which direction does Carbonic Anhydrase function in body tissue?
CO₂ + H₂O →(via Carbonic anhydrase) H₂CO₃→ HCO⁻₃ + H⁺ - thus, CO₂ from tissues causes the decrease of blood pH. - In tissues, carbonic anhydrase creates HCO⁻₃ and H⁺ ions, thereby making blood more acidic
Prokaryotes do not have any complex, membrane-bound organelles - T or F?
True
What are the identification techniques to finding an X-linked recessive inheritance pattern?
Can skip generations Affects males more than females Affected female has all affected sons, but can have both affected and unaffected daughters
What are six major things that differentiate cancer cells from normal cells?
Cancer cells continue to grow and divide in situations normal cells would not. Cancer cells fail to respond to cellular controls and signals that would halt this growth in normal cells. Cancer cells avoid apoptosis (self-destruction) that normal cells undergo when extensive DNA damage is present. Cancer cells stimulate angiogenesis (cause new blood vessels to grow to nourish the cancer cell). Cancer cells are immortal while normal cells die after a number of divisions. Cancer cells can metastasize - break off and then grow in another location.
What effect does Carbon Monoxide have on the oxygen dissociation curve?
Carbon Monoxide has more than 200 times greater affinity for Hb than does oxygen but it shifts the curve to the left.
Which enzyme governs the formation of bicarbonate ion?
Carbonic anhydrase in the reversible reaction: CO₂ + H₂O → HCO⁻₃ + H⁺ This creates the Bohr Effect
Digestion begins with ____ in the mouth via _______. There is no digestion in the _____.
Carbs (STARCH); amylase in saliva Esophagus
Can cardiac muscle grow?
Cardiac muscle can grow via hypertrophy
What is the role of the intercalated disc within the cardiac muscle?
Cardiac muscle consists of single heart muscle cells (cardiomyocytes) which have to be connected by intercalated discs to support synchronised contraction of cardiac tissue.
What is the role of the intercalated disc within the cardiac muscle?
Cardiac muscle consists of single heart muscle cells (cardiomyocytes) which have to be connected by intercalated discs to work as a functional organ. By contrast, skeletal muscle consists of multinucleated muscle fibers and therefore exhibit no intercalated discs. Intercalated discs support synchronised contraction of cardiac tissue. They can easily be visualized by a longitudinal section of the tissue.
Is cardiac muscle voluntary or involuntary?
Cardiac muscle is involuntary
Describe Cardiac muscle cells:
Cardiomyocytes have a single nucleus, a sarcolemma, sarcoplasmic reticulum, and transverse tubules.
Is cartilage vascular and if so, what part of it is vascular?
Cartilage is avascular, contains no blood vessels or nerves except in its outside layer called the perichondrium.
What is cartilage composed of?
Cartilage is composed of collagen thus has great tensile strength. - Cartilage is composed of specialized cells called chondroblasts that produce large amounts of extracellular matrix composed of collagen, proteoglycan and elastin fibres.
What is Cartilage?
Cartilage is flexible, resilient connective tissue. - is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the bronchial tubes and the intervertebral discs. It is not as hard and rigid as bone but is stiffer and less flexible than muscle. - Cartilage is composed of specialized cells called chondroblasts that produce a large amount of extracellular matrix composed of collagen fibers, abundant ground substance rich in proteoglycan, and elastin fibers. Cartilage is classified in three types, elastic cartilage, hyaline cartilage and fibrocartilage, which differ in the relative amounts of these three main components.[1] Chondroblasts that get caught in the matrix are called chondrocytes. They lie in spaces called lacunae with up to eight chondrocytes per lacuna. Unlike other connective tissues, cartilage does not contain blood vessels. The chondrocytes are supplied by diffusion, helped by the pumping action generated by compression of the articular cartilage or flexion of the elastic cartilage. Thus, compared to other connective tissues, cartilage grows and repairs more slowly.
_____ joints allow little to no movement. They occur between two bones tightly connected by _____, such as the ribs and the sternum, or the pubic symphysis in the hip bone.
Cartilaginous joints allow little to no movement. They occur between two bones tightly connected by cartilage, such as the ribs and the sternum, or the pubic symphysis in the hip bone.
Describe Cell-Mediated immunity and how it works:
Cell-mediated immunity involves T-Lymphocytes - T lymphocytes mature in the thymus - T lymphocytes have an antibody-like protein at their surface that recognizes antigens. - T lymphocytes never make free antibodies - In the thymus, T lymphocytes are tested against self-antigens, which are antigens expressed by normal cells of the body - If the T lymphocyte binds to a self-antigen, the T lymphocyte is destroyed in order to prevent auto-immune diseases - If it does not bind to a self-antigen, it is released to lodge in lymphoid tissue or to circulate between the blood and lymph fluid - T lymphocytes that are not destroyed, differentiate into Helper T cells, Memory T cells, Suppressor T cells and Killer T cells(also called Cytotoxic T cells) - The T helper cells assist in activating B lymphocytes as well as killer and suppressor T cells. - An infected cell signals for its own death by presenting some of the antigen on its surface through the class I MHC molecule and then its destroyed by an activated cytotoxic T cell
What carb can't be digested in humans?
Cellulose (the polysaccaride that makes of plant cell wall)
What are ceruminous glands and where are they found?
Ceruminous glands produce the wax-like material in the ears.
What is the process by which neutrophils are drawn towards injured or infected tissues?
Chemotaxis
The entire DNA/protein complex, with very small amounts of RNA, is called?
Chromatin
____ ______ occur when a portion of the chromosome breaks off, or when a portion of the chromosome is lost during homologous recombination and/or crossing over events.
Chromosomal Deletions
The genes that produce the A and B antigens are ____.
Co-dominant, thus an individual having the type A or B blood may be heterozygous or homozygous.
How do collagen fibres add tensile strength to bones?
Collagen fibres lie along the line of tensile force of the bone, giving the bone great tensile strength.
____ bone is highly structured and vascular and is organized by the Haversian System.
Compact Bone
What type of bone surrounds the medullary cavity or marrow cavity of long bone?
Compact bone surrounds the medullary cavity, which holds the yellow bone marrow. - compact bone is highly organized
What is the difference between complete dominance and co-dominance?
Complete dominance Genotype Phenotype AA Dominant Aa Dominant aa Recessive Co-dominance Genotype Phenotype AA A AB Both A and B BB B
What is the difference between constant and variable expressivity?
Constant expressivity means that if your genes for being smart manages to penetrate (show up as a trait), then your IQ is 120. Variable expressivity means that your IQ doesn't have to be 120, it could be somewhat lower or somewhat higher
Calmodulin or G-proteins are examples of what kind of proteins?
Control proteins
Once inside the matrix, what happens to pyruvate?
Converted to acetyl CoA
What is Cooperative Binding?
Cooperative binding is a special case of allostery. Cooperative binding requires that the macromolecule have more than one binding site, since cooperativity results from the interactions between binding sites. If the binding of ligand at one site increases the affinity for ligand at another site, the macromolecule exhibits positive cooperativity. Conversely, if the binding of ligand at one site lowers the affinity for ligand at another site, the protein exhibits negative cooperativity. If the ligand binds at each site independently, the binding is non-cooperative. - Hb exerts cooperativity, in that as soon as one O₂ molecule binds to heme in Hb, binding at the other 3 heme sites increases in ease and speed. - conversely, once one heme group loses an O₂ molecule, it becomes easier for the other 3 heme groups to loses their O₂ molecules.
What are the 2 types of coenzymes
Cosubstrates and prosthetic groups
What is "crossing over" refer to, and how is it related to genetic linkage?
Crossing over is a mechanism that reduces linkage. However, crossing over is only efficient when the genes are physically apart from each other on the chromosome. When the genes are further apart on the chromosome, crossing over makes them less linked. The physically closer the genes are on the chromosome, the more linked they are.
Fill in the blanks: Crossing over occurs during _____ (the actual site of cross over is the ______, which is made possible because of pairing of homologous chromosomes called the ____, which is formed by a process called ______).
Crossing over occurs during prophase I (the actual site of cross over is the chiasma. The chiasma is made possible because of pairing of homologous chromosomes called the tetrad, which is formed by a process called synapsis).
____ T cells bind to an antigen-carrying cell and release perforin to puncture and lyse the infected cell.
Cytotoxic T cells
T/F. Most fungi have both a haploid and a diploid stage of life cycle.
True
Prokaryotes do not have ribosomes - T or F?
False - prokaryotes do have ribosomes; 50S + 30S subunits = 70S ribosome
What is the Central Dogma of Gene Expression?
DNA is transcribed to RNA, which is then translated to amino acids forming a protein. DNA is transcribed to RNA, RNA is translated to protein
Which protein connects the okazaki fragments together?
DNA ligase
mitochondrial DNA
DNA that is passed maternally
What is the correlation between DNA binding proteins and transcription factors?
DNA-binding proteins bind to DNA. transcription factors bind to DNA, so they have a DNA-binding domain. DNA-binding domains interact with the grooves in the double helix (major grooves and minor grooves)
lipolysis
Decomposition of fats., splitting of fats into glycerol and fatty acids
What is anemia?
Decreased red blood cell count
Non-competitive inhibition does what to the maximum possible rate of the enzyme's catalysis.
Decreases
Where are Chief cells found? What is the purpose of these cells?
Deep in the exocrine glands. They secrete pepsinogen, the zymogen precursor to pepsin. -Pepsinogen is activated to pepsin by the low pH in the stomach. Once activated, pepsin begins protein digestion.
What are the differences between translocation, deletion, and mispairing?
Deletion = a base is taken out of the DNA sequence. Translocation = a stretch of DNA (a segment of a chromosome) breaks off, then reattaches somewhere else. Mispairing = A not pairing with T, or G not pairing with C.
______ occur when a DNA fragment breaks free of one chromosome and incorporates into a homologous chromosome.
Deletions
What are the dense bodies found in smooth muscle cells?
Dense bodies in smooth muscle cells are electron-dense portions of smooth muscle which thin filaments (actin and tropomyosin namely) bind to.
What is the Haldane Effect?
Deoxygenation of the blood increases its ability to carry carbon dioxide; this property is the Haldane effect. Conversely, oxygenated blood has a reduced capacity for carbon dioxide.
What is the function of the SER
Detoxification and glycogen breakdown in liver; steroid synthesis in gonads
Kussmaul breathing
Diabetic ketoacidosis. Deep, labored breathing/hyperventilation to blow off CO2., air hunger or labored breathing
What is the process called by which both monocytes and neutrophils enter the damaged or infected tissues?
Diapedesis
_____ is "minimum pressure" in the arteries, which occurs near the beginning of the cardiac cycle when the ventricles (and atria) are filling with blood.
Diastolic pressure.
What are the identification techniques to finding an autosomal dominant inheritance pattern?
Doesnt skip generations Affected males=affected females Affected parent passes the trait to either all or half of the offspring
What are the identification techniques to finding an X-linked dominant inheritance pattern?
Doesnt skip generations Usually affects males more Affected fathers have all affected daughters Affected mothers can have unaffected sons, and pass the trait equally to sons and daughters Hardest to identify
Why would sudden vasodilation occur in flush skin just prior to frostbite in extreme cold?
Due to the paralysis of smooth muscle in the vascular walls.
Explain what happens to the sarcomere and its filaments as contraction occurs:
During contraction, myosin filaments force actin filaments to move closer to each other, pulling the Z bands closer together. - the H zone gets shorter as contraction occurs, because the H zone is the distance between adjacent actin filaments within the same sarcomere - the I band also gets shorter because this is the distance between actin filaments of adjacent sarcomeres. - The A band remains the same length because it is the length of the myosin filaments of a single sarcomere.
What happens to the diaphragm during inhalation?
During inhalation, the diaphragm contracts and flattens, coming down from its dome-shape, and the external intercostal muscles contract (pushing the rib cage up and out): this increases the volume of the thoracic cavity while reducing the pressure inside the lungs, causing them to fill with air due to the atm pressure. (Negative pressure breathing)
Describe the mechanism of independent assortment
During metaphase I of meiosis, homologous chromosome pair up along the metaphase line in random orientation - sometimes the mom's chromosome is on the left, sometimes it's on the right. During anaphase I of meiosis, the homologous chromosomes are pulled apart. Those on the left will be put into one daughter cell, those on the right will be put into another
What bacteria lives in the large intestines?
E. coli.
endocytosis
ER lumen can be reached without transporting across a membrane via ___
What surrounds the bronchioles of the lungs?
Each bronchiole is surrounded by a cluster of small air sacs called alveoli within which gas exchange occurs - Bronchioles are also wrapped in smooth muscle
What is a replication unit or replicon?
Each chromosome of euk DNA is replicated in many discreet segments.
True or false: Mutagens are almost always carcinogens. Not all carcinogens are mutagens.
False. Carcinogens are almost always mutagens. Not all mutagens are carcinogens.
Describe the multi-unit smooth muscle cells:
Each multi-unit smooth muscle fibre is attached directly to a neuron - a group of multi-unit fibres can contract independently of other muscle fibres in the same location - Multi-unit smooth muscle is found in the large arteries, bronchioles, pili muscles attached to hair follicles, and the iris. - basically, each muscle fibre is innervated by a different neuron, allowing the contraction of single muscle fibres at different times.
_____ is a powerful vasoconstrictor causing arteries to narrow
Epinephrine
What do the myeloid stem cells divide into?
Erythrocytes, platelets, monocytes, neutrophils, eosinophils, basophils
How many copies of genes to euks and proks have?
Euks can have more than one copy, whereas Proks only have one copy.
How many origins of replication do euks have compared to proks?
Euks= many Proks= 1
Why can't all physical traits of an organism be mapped to a single locus?
Every gene is located at a specific locus, but physical traits that are complex like weight or height can be controlled by many different genes.
Most tissues are drained by lymphatic channels except what?
Except the central nervous system.
Describe the oxygen dissociation curve for exercising muscle:
Exercising muscle would have a great right shifted curve, as more H⁺ ions, Heat and CO₂ would be produced... thus, facilitating more oxygen unloading into the tissue by Hb.
During _____, the diaphragm relaxes back to its dome-shaped position.
Exhalation - rib cage gets smaller as external intercostal rib muscles relax
Is exhalation passive or forced?
Exhalation is passive as the lungs and chest are highly elastic and tend to recoil to their original position once the diaphragm is relaxed.
Fill in the blanks: Prokaryotes: Existence of plasmids, extragenomic DNA, transfer by _______ Plasmids are ______ stranded DNA. A plasmid can exist and replicate independently of the genomic DNA, or be integrated into it. Plasmids are ______(inherited/non-inherited). Plasmids are __________(essential/not essential) for growth and reproduction in the wild. __________ transfers genetic material between bacteria via a pillus. A bacteria able to make the pillus (F+) has a plasmid that contains the pillus genes. _____ bacteria can transfer the plasmid to an ____ bacteria. Conjugation can also transfer some genomic DNA (because ______________)
Existence of plasmids, extragenomic DNA, transfer by conjugation Plasmids are double stranded DNA. A plasmid can exist and replicate independently of the genomic DNA, or be integrated into it. Plasmids are inherited. Plasmids are not essential for growth and reproduction in the wild. Conjugation transfers genetic material between bacteria via a pillus. A bacteria able to make the pillus (F+) has a plasmid that contains the pillus genes. F+ bacteria can transfer the plasmid to an F- bacteria. Conjugation can also transfer some genomic DNA (because F+ plasmid can integrate into the chromosome).
What is epistasis?
Expression of alleles for one gene is dependent on a different gene
Hexokinase, the first enzyme in glycolysis, is inhibited by its product glucose-6-phosphate. In general, what is this an example of?
Feedback inhibition.
Prokaryotes do not have organelles - T or F?
FALSE. they do not have complex, membrane-bound organelles but do have organelles such as ribosomes, nucleoid, mesosomes, etc.
Is this statement true or false: A gene may have a number of alleles. All alleles of the same gene exist sometimes a different loci, and other times at the same locus.
False. A gene may have a number of alleles, however all alleles of the same gene exist at the same locus.
True or False: After some time, RNA is degraded. In most cases, the rate and timing of RNA degradation cannot be controlled naturally by the cell without some form of synthetic intervention.
False. After some time, RNA is degraded. The rate and timing of RNA degradation CAN be controlled by the cell.
T/F. If an individual has two different alleles at a given locus, there are two alleles in one place on one particular chromosome
False. There is a different allele on each of the two members of a homologous pair.
T/F. If the color gene and the shape gene are right next to each other on a chromosome, they will display independent assortment
False. They will display linkage
How is the curve for Fetal Hb compared to that for adult Hb?
Fetal Hb has a higher affinity for O₂ than adult Hb, thus it has a left-shifted curve compared to adult Hb, because of a reduced affinity for 2,3-BPG/DPG
Where are the fibroblasts located and what is their purpose?
Fibroblasts are located in the dermis, they make fiber and ground substances for the ECM that holds this connective tissue together.
_____ joints hold two bones tightly together with ____ tissue, allowing for little movement, as in the skull.
Fibrous joints hold two bones tightly together with fibrous tissue, allowing for little movement. - Skull bones form fibrous joints with each other, and the teeth form fibrous joints with the mandible.
Describe the retrovirus life cycle
First, retrovirus enters the host. The viral reverse transcriptase then converts the viral RNA genome into double-stranded DNA. A virally encoded enzyme called integrase adds in the viral DNA into the host's genome at a random place. When the host replicates, the viral DNA gets replicated also.
In which types of bone is red marrow found?
Flat bones and at the epiphyseal ends of long bones
In which types of bone is red marrow found?
Flat bones and in the cancellous (spongy) material at the epiphyseal ends of long bones
Describe the shape and composition of flat bones:
Flat bones are made from spongy bone surrounded by compact bone. They provide large areas for muscle attachment, and organ protection. - The skull, sternum, ribs and shoulder blades are flat bones
What does it mean that the lymph system is an open system?
Fluid enters at one end and leaves at the other end. Lymph capillaries are like tiny fingers protruding into tissues. - to enter the lymph system, interstitial fluid flows between overlapping endothelial cells. - large particles literally push their way between the cells into the lymph - the cells overlap in such a fashion that once inside, large particles cannot push their way out.
Summarize the immune response:
For a Bacterial Infection: Humoral/B cell immunity: - Inflammation - Macrophages then neutrophils move in to engulf bacteria - Interstitial fluid is flushed into the lymphatic system where lymphocytes wait in the lymph nodes - Macrophages process and present the the bacterial antigens to B lymphocytes - B lymphocytes with the help from Helper T cells are able to differentiate into into Memory B cells and plasma cells - plasma cells produce free antibodies and mast cell bound antibodies - Memory B cells remain in blood in preparation for a secondary infection
If nts are added in multiples other than 3, what type of mutation will occur?
Frameshift
What are the 2 things that can activate B lymphocytes?
Free antigens or Helper T-cells
What happens to oxygen from each alveolus?
From each alveolus oxygen diffuses into a capillary where it is picked up by red blood cells. - these red blood cells release carbon dioxide, which diffuses into the alveolus, and is expelled upon exhalation.
brush border
Fuzzy coverings of microvilli. They contain membrane bound digestive enzymes.
second messenger
G-proteins commonly activate ___ systems
Muscles and nerves are an example of components of what phase of the cell cycle?
G0 (no more DNA replication or cell division)
Describe the 5 phases of the cell cycle
G0 = no more DNA replication or cell division. G1 = growth = make organelles, increase in cell size. S = DNA replication. Centrioles also replicated. G2 = growth = make organelles, increase in cell size. M = mitosis.
What is the interphase of the cell cycle?
G1 = Growth S = Synthesis (replicate DNA) G2 = Growth
Through which type intra-cellular junctions are cardiac contraction signals spread?
Gap Junctions
Are genes close together or further apart from each other more likely to cross over together?
Genes closer together on a chromosome are more likely to cross over together, and are said to be linked.
How is genetic recombination tied with genetic variability?
Genetic recombination is the product of independent assortment and crossing-over, which introduces genetic variability.
What does Mitosis result in?
Genetically identical diploid daughter cells
What is incomplete dominance?
Genotype Phenotype AA A AB In between A and B BB B
Lack of insulin---- Increased secretion of:
Glucagon,Cortisol,Growth hormone Catecholamines
What mainly occurs in the liver?
Gluconeogenesis: production of glycogen from noncarbohydrate precursors
80% of the end product of carb digestion is __. 95% of carbs in blood is the same.
Glucose
Respiration reaction formula
Glucose + O2 --> CO2 + H2O (combustion reaction)
When glycogen stores are full what happens?
Glucose is converted to fat, a long-term form of energy storage. This conversion takes place in the liver and fat cells and is stored in the fat cells.
Lack of insulin----catabolism---
Glycogenolysis + Gluconeogenesis + lipolysis (weight loss) ---Hyperketonaemia-----acidosis( hyperventilation (hypertention/ hypothermia))--Diabetic ketoacidosis death.
What are the steps of anaerobic metabolism?
Glycolysis Alcohol or lactic acid fermentation
What are the steps of aerobic metabolism?
Glycolysis Oxidative decarboxylation Krebs cycle Electron transport chain.
When undergoing physical exercise, healthy adult skeletal muscle is likely to respond with an increase in what?
Glycolysis, CAC, and Protein production
Which organelle can glycosylate proteins as well as modifying existing glycosylations.
Golgi apparatus
What are the granular leukocytes?
Granulocytes are named based on their staining properties Neutrophils, Eosinophils and basophils
What is the life of a granulocyte like?
Granulocytes remain in the blood for 4 to 8 hours before they are deposited in the tissues, where they live for 4 to 5 days.
An individual exposed to a pathogen for the first time will exhibit an innate immune response involving:
Granulocytes: neutrophils, basophils and Eosinophils
The greater the pressure of carbon dioxide, the _____ the blood content of carbon dioxide.
Greater
Guanine forms ____ H-bonds with ___?
Guanine forms 3 H-bonds with cytosine
In which direction does Carbonic Anhydrase function in the lungs?
HCO⁻₃ + H⁺ → H₂CO₃ →(via carbonic anhydrase) CO₂ + H₂O - thus, in the lungs carbonic anhydrase creates H₂O and CO₂, which are then expelled - this effectively lowers blood H⁺ concentration and increases pH.
HIV attacks which cells of the immune system?
HIV attacks the Helper T cells of the Cell-mediated immune system
How is hair on the skin involved in keeping the body warm?
Hair can be erected (piloerection) via sympathetic stimulation trapping insulating hair next to the skin.
What is hair?
Hair is a column of keratinized cells held tightly together. - most hairs are associated with a sebaceous (oil) gland that empties oil directly into the follicle and onto the skin.
What is hair?
Hair is a column of keratinized cells held tightly together. as new cells are added to its base, the hair grows. - most hairs are associated with a sebaceous (oil) gland that empties oil directly into the follicle and onto the skin. - when contracted, smooth muscle (arrector pili), also associated with each hair, stands hair up pointing it perpendicular to the skin.
How can Haptens stimulate an immune response?
Haptens can only stimulate an immune response if the body had previously been exposed to the full antigen.
_____ canals contain lymph and blood vessels which are cross-linked by Volkmann's Canals.
Haversian
amphipathic
Having both a hydrophilic region and a hydrophobic region.
What type of muscle is heart muscle composed of?
Heart muscle is composed mainly of cardiac muscle.
Pulse is a direct measure of?
Heart rate or beats per minute
One of the jobs of the gastrointestinal hormones is to?
Help regulate digestion process
____ T cells, the ones attacked by HIV, recognize APC macrophages and activate required B cells and cytotoxic T cells for both humoral and cell-mediated immunity
Helper T cells
The percentage by volume of red blood cells is called the _____.
Hematocrit, which is normally 35-55% and is greater in men than in women.
What is the Bohr Effect?
Hemoglobin's oxygen binding affinity is inversely related both to acidity and to the concentration of carbon dioxide. That is to say, a decrease in blood pH or an increase in blood CO₂ concentration will result in hemoglobin proteins releasing their loads of oxygen and a decrease in carbon dioxide or increase in pH will result in hemoglobin picking up more oxygen. Since carbon dioxide reacts with water to form carbonic acid, an increase in CO2 results in a decrease in blood pH. - This effect facilitates oxygen transport as hemoglobin binds to oxygen in the lungs, but then releases it in the tissues, particularly those tissues in most need of oxygen. When a tissue's metabolic rate increases, its carbon dioxide production increases. - Although the reaction usually proceeds very slowly, the enzyme family of carbonic anhydrase, which is present in red blood cells, accelerates the formation of bicarbonate and H⁺ ions. This causes the pH of tissues to decrease, and so, promotes the dissociation of oxygen from hemoglobin to the tissue, allowing the tissue to obtain enough oxygen to meet its demands. - Conversely, in the lungs, where oxygen concentration is high, binding of oxygen causes hemoglobin to release protons, which combine with bicarbonate to drive off carbon dioxide in exhalation. Since these two reactions are closely matched, there is little change in blood pH. The dissociation curve shifts to the right when carbon dioxide or hydrogen ion concentration is increased. This facilitates increased oxygen dumping. This mechanism allows for the body to adapt the problem of supplying more oxygen to tissues that need it the most. When muscles are undergoing strenuous activity, they generate CO2 and lactic acid as products of cellular respiration and lactic acid fermentation. In fact, muscles generate lactic acid so quickly that pH of the blood passing through the muscles will drop to around 7.2. As lactic acid releases its protons, pH decreases, which causes hemoglobin to release ~10% more oxygen.
____ consists of 4 globular protein subunits, each connected to a prosthetic heme group.
Hemoglobin: - the globular protein has 2 beta chains and 2 alpha chains. = each chain has a heme group, each heme group is capable of binding one molecule of oxygen (O₂) - the Fe in the heme group is what associates with the oxygen molecule.
What is Hemopoiesis, and within which type of bone does Hemopoiesis occur?
Hemopoiesis is the production of red blood cell. This occurs inside the red bone marrow contained in spongy bone. Platelets and most white blood cells also arise in red bone marrow
Within which type of bone does Hemopoiesis occur?
Hemopoiesis is the production of red blood cell. This occurs inside the red bone marrow contained in spongy bone. Platelets and most white blood cells also arise in red bone marrow
Eukaryotic genes that are not being actively transcribed are associated with tightly packed regions of DNA called?
Heterochromatin; this is where repetitive sequence DNA is mainly found.
What are some of the causative agents of inflammation that are released by tissues?
Histamine, prostaglandins and lymphokines
What amino acid is a good buffer at physiological pH
Histidine
What charge are histones and what causes this?
Histones have a net positive charge due to their basicity from their large basic amino acid content. The net positive charge of histones allows DNA to wrap and adhere even tighter because DNA had a net negative charge.
Describe the two chromosomal proteins
Histones: responsible for the compact packing and winding of chromosomal DNA. DNA winds itself around histone octamers. nonhistone chromosomal proteins: all the other proteins are lumped together in this group. Responsible for various roles, such regulatory and enzymatic.
Describe Humoral or B-cell Immunity and how it works:
Humoral/B-cell Immunity is promoted by B lymphocytes - Each B lymphocyte is capable of making a single type of antibody or immunoglobulin, which it displays on the surface of its plasma membrane. - antibodies recognize foreign particles called antigens - the portion of an antibody that binds to an antigen is highly specific for that antigen. - the portion of the antigen that binds to the antibody is called an Antigenic determinant. - Haptens are an antigenic determinant that has been removed from the antigen - the hapten can only elicit an immune response if the body had been previously exposed to the full antigen. - When a macrophage engulfs a microbe, the macrophage presents the antigenic determinant of that microbe on its cell surface. - If the B lymphocyte antibody contacts a matching antigen that is on the surface of one of these macrophages, the B lymphocyte, assisted by a helper T-cell, will differentiate into plasma cells and memory B-cells. - the plasma cells then begin to synthesize free antibodies and release them into the blood - These free antibodies may attach their bases to Mast cells. - When an antibody, whose base is bound to a mast cell, also binds an antigen, the mast cell releases histamine and other chemicals. - when other free antibodies contact the specific antigen, they bind to it - once bound, the antibodies may begin a cascade of reactions involving blood proteins (called complement) that cause the antigen bearing cell to be perforated - the antibodies may also mark the antigen for phagocytosis by macrophages and NK cells - the antibodies may cause the antigenic substances to agglutinate or even precipitate, or, in the case of a toxin, the antibodies may block its chemically active portion.
What type of bond holds the two antiparallel strands of DNA together?
Hydrogen bonds; called base pairing
All macronutrients are digested by what reaction?
Hydrolysis
Although osmotic pressure remains relatively constant through out the capillary, what happens to hydrostatic pressure?
Hydrostatic pressure drops from the arteriole end of the capillary to the venule end of the capillary.... Thus, osmotic pressure overcomes hydrostatic pressure near the venule end of a capillary, and net fluid flow is into the capillary and out of the interstitium. - Remember that the capillary lies between the arterioles and the venules... it is the place of fluid, nutrient and gas exchange.
As blood flows into a capillary, _____ pressure is greater than _____ pressure and a net flow of fluid occurs out of the capillary and into the interstitium.
Hydrostatic pressure is greater than osmotic pressure.
How do Hydroxyapatite crystals give the bones greater compressive strength?
Hydroxyapatite crystals lie alongside the collagen fibres, and give the bone better compressive strength than the best reinforced concrete.
Lack of insulin--> decrease anobolism----->
Hyperglycaemia (fatigue)---->Glycosuria (Vulvitis)--->Osmotic diuresis(Polyuria,Polydipsia)--->Salt and water depletion (Tachycardia, Hypotension)----> Death
What is the increase in muscle cell diameter and change in muscle conformation called? What is the condition where muscle cells remain approximately the same size but increase in number.
Hypertrophy hyperplasia
What is the increase in muscle cell diameter and change in muscle conformation called?
Hypertrophy: is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It should be distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number.
What is the I Band of a sarcomere?
I-band is the zone of thin filaments (actin) that is not superimposed by thick filaments. - this is also the region between neighbouring sarcomere units and the Z-band.
Why can't a haploid organism like an adult fungus have recessive alleles?
If there is only one copy of a gene, then that is the copy which determines the phenotype
In regards to transcription, what is the primary difference between eukaryotes and prokaryotes?
In eukaryotes, enhancers/silencers can be very far away from the actual promoter, and can be upstream or downstream. The DNA must loop back on itself so that the transcription factor bound to enhancer/silencer can actually make contact with the promoter. Intermediate proteins are involved in the process.
Where is the ribosome assembled in euks and in proks?
In euks it is assembled in the nucleolus then exported to the cytoplasm. In proks, there is no nucleolus but assembly is similar.
How are the ribosome and its subunits measured?
In terms of sedimentation coefficients given in Svedberg units (S). The sedimentation coefficient gives the speed of a particle in a centrifuge, is proportional to mass, and related to shape and density.
In which direction does DNA poly build a new strand of DNA?
In the 5'→3' direction
Where are large amounts of Type II A fibres found?
In the Upper legs
Where to B-cells mature into B-Lymphocytes?
In the bone marrow
Where do B-lymphocytes mature and differentiate?
In the bone marrow and the liver
Where does gas exchange between blood and tissues occur?
In the capillaries
Where are the gamma globulins that constitute antibodies formed?
In the lymph tissue
What is the relationship between smooth ER and our muscles?
In the muscles, the SER or SR stores and regulates calcium.
Where does Post transcriptional processing of the mRNA occur in eukaryotes?
In the nucleus
Where is the dermis thickest?
In the palms and soles
Where are large amounts of Type I fibres found?
In the postural muscles.
*Filtration occurs?
In the renal corpuscle of the nephron
Where are large amounts of Type II B fibres found?
In the upper arms
PKU (Phenylketonuria) is an inborn error of metabolism where people can't metabolize phenylalanine. There's no cure, but the treatment involves avoiding things containing the amino acid phenylalanine. What is this an example of?
Inborn errors of metabolism
What do enzymes do for k in the equation: rate=k[A][B] ?
Increase
If the secretion of HCL from the parietal cells of the stomach is blocked what would happen to the microbial activity in stomach, activity of pepsin and pH of stomach?
Increase in microbial activity; decrease in pepsin; increase in stomach pH
Competitive inhibition does what to the amount of substrate needed to achieve maximum catalysis?
Increases
What is independent assortment?
Independent assortment generates genetic variation. A cell has 2 copies of each somatic chromosome- one from mom, one from dad (homologous chromosomes). Independent assortment shuffles these chromosomes, and then places only one copy of each into the gamete. This way, the gamete may have chromosome 1 from mom, chromosome 2 from dad, chromosome 3 from dad, ... etc.
What is cell-mediated immunity effective against?
Infected cells
What are the 5 assumptions of hardy-weinberg?
Infinitely large population (no genetic drift) No mutation No migration Random mating (no sexual selection) No natural selection
Part of the effect of _____ is to 'wall-off' the effected tissue and local lymph vessels from the rest of the body, impeding the spread of the infection.
Inflammation
What is Inflammation?
Inflammation is a vascular tissue response to harmful stimuli, such as pathogens, damaged cells or irritants. - This response is a protective attempt to stop the stimulus from spreading to other tissues and to initiate the healing process.
Vulvitis
Inflammation of the external female genital structure
What results from injury to tissues?
Inflammation, which includes dilation of blood vessels, increased permeability of capillaries, swelling of tissue cells, and migration of granulocytes and macrophages to the inflamed area.
During _____, the diaphragm contracts by moving down and flattening from its original dome-shaped position.
Inhalation - rib cage expands as rib muscles contract (external intercostals contract), volume of chest cavity (thoracic) expands - causing negative pressure in the chest/lungs, thus the atm pressure forces air into lungs
FOR MCAT, fat is ____ in water, so it requires? You should associate fat with ____
Insoluble; a carrie (i.e. a lipoprotein, or albumin) *efficient long-term energy storage; lots of calories (energy) with little weight
What part of the brain is involved in inspiration of air?
Inspiration of air occurs when the medulla oblongata of the midbrain signals the diaphragm to contract.
What hormone inhibits glycogenolysis?
Insulin
What role do the intercostal muscles play?
Intercostal muscles or those muscles between the ribs also help to expand the chest cavity while breathing.
What are G₁, S and G₂ collectively referred to as?
Interphase; Interphase is the phase of the cell cycle in which the cell spends the majority of its time and performs the majority of its purposes including preparation for cell division. In preparation for cell division, it increases its size and makes a copy of its DNA. Interphase is also considered to be the 'living' phase of the cell, in which the cell obtains nutrients, grows, reads its DNA, and conducts other "normal" cell functions[citation needed]. The majority of eukaryotic cells spend most of their time in interphase. Interphase does not describe a cell that is merely resting but is rather an active preparation for cell division. A common misconception is that interphase is the first stage of mitosis. However, since mitosis is the division of the nucleus, prophase is actually the first stage.[1] In interphase, the cell gets itself ready for mitosis or meiosis. Somatic cells, or normal diploid cells of the body, go through mitosis in order to reproduce themselves through cell division, whereas diploid germ cells (i.e., primary spermatocytes and primary oocytes) go through meiosis in order to create haploid gametes (i.e., sperm and ova) for the purpose of sexual reproduction. Chromosomes are copied.
True or False. Glycolysis occurs in both anaerobic and aerobic environments.
True
What is the mutation called when the orientation of a section of DNA is reversed on a chromosome?
Inversion
Describe the shape and composition of irregular bones:
Irregular bones have an irregular shape and variable amounts of compact and spongy bone
Agents which covalently bind to enzymes and disrupt their function.
Irreversible inhibitors
What role does myoglobin play?
It allows O₂ to be stored in muscles for long periods of time. It has an instant binding affinity for oxygen and is found only in muscle tissue to allow for immediate release of oxygen when needed.
What does variation from a consensus sequence (most common NT sequence in promoter) cause RNA poly to do?
It causes RNA poly to bond less tightly and less often to a given promoter, which leads to those genes being transcribed less frequently.
Competitive inhibition does what to the maximum possible rate of the enzyme's catalysis.
It does not change it.
What role does the nasal cavity play in breathing?
It filters, moistens and warms incoming air. - coarse hair at the front of the cavity traps large dust particles - mucous secreted by goblet cells traps smaller dust particles and moistens the air - capillaries within the nasal cavity also warm the air
Renin function?
It is an enzyme secreted by juxtaglomerular apparatus to initiates a regulatory cascade producing angiotension I, II, and III, which stimulates the adrenal cortex to secrete aldosterone.
What is Myoglobin?
It is an oxygen binding molecule that consists of a single polypeptide chain and has only one heme group which binds to only one O₂ molecules. - It does not exhibit cooperative binding because it only has one heme group
Where is carbon dioxide partial pressure greatest?
It is greatest in the blood in the systemic capillary beds than in the alveoli of the lungs... this allows CO₂ to travel from highest pressure to lowest pressure, and thus into the alveoli of the lungs from the capillary beds, to be exhaled.
Why is oxygen necessary for aerobic respiration?
It is the final electron acceptor
What is Nucleic Acid Hybridization and what does it allow?
It is the formation of DNA-DNA, DNA-RNA, or RNA-RNA double stranded combinations that allow scientists to identify nucleotide sequences by binding a known sequence with an unknown sequence.
What does it mean that a restriction site is palindromic?
It reads the same backwards as forwards and is 4 to 6 nucleotides long.
When one of a pair of antagonistic muscles contracts, what usually happens to the other muscle to produce movement?
It relaxes to allow movement
What is hypovolemic shock and when is it most likely to occur?
It represents a set of symptoms that occur when a patient's blood volume drops abruptly and is most likely to occur via arterial bleeding.
What effect does 2,3-BPG or 2,3-DPG have on the Oxygen Dissociation curve and why?
It shifts the curve to the right by binding to partially deoxygenated Hb to facilitate complete O₂ unloading
What are the main components involved in the coagulation process?
It starts with platelets and includes the plasma proteins prothrombin→thrombin via prothrombin activator enzyme, and fibrinogen→fibrin via thrombin
What does exposure to friction or pressure stimulate the epidermis to do?
It stimulates the epidermis to thicken forming a callus.
How does the body keep the body warm via the skin?
It will shunt blood away from the capillaries of the skin to reduce heat loss, keeping the body warm.
Would it be better to rest or exercise following a meal? Explain:
It would be better to rest because activation of the sympathetic NS via exercise increases vasodilation of blood vessels to the active muscle tissue and vasoconstriction of blood vessels to digestive organs.
E. coli produce vitamin. What is the mutalistic symbiosis between humans and bacteria in the large intestine?
K, B12, thiamin, and riboflavin -Bacteria get our leftovers; we get certain vitamins
What are the types of T-Cells?
Killer T cells also called cytotoxic T cells Helper T cells Memory T cells Suppressor T cells
Which type of T cell is responsible for fighting forms of cancer and for attacking transplanted tissue?
Killer/Cytotoxic T cells
What cells destroy irregular erythrocytes in the liver, where are most destroyed?
Kupfer cells ; spleen
hormones of the anterior pituitary (peptide)
LH FSH ACTH hGH TSH Prolactin
What is the area in which an osteocyte resides called?
Lacuna
Viral infection stages (4)
Landing, attachment, tail contraction, penetration and injection
Type I slow twitch muscle fibres contain large amounts of _____ for what reason?
Large amounts of mitochondria - they are slow to fatigue but also have a slow contraction velocity because they split ATP at a slow rate. - Type I slow twitch muscle fibres are resistant to fatigue.
Why are large arteries less affected by sympathetic innervation?
Large arteries have less smooth muscle per unit volume than medium arteries, and are thus less affected by sympathetic innervation.
What are the infectious agents that are able to pass through the skin or digestive defences and enter the body first attacked by?
Local Macrophages - these phagocytic giants can engulf as many as 100 bacteria - these macrophages then stimulate the activation of the acquired immunity response.. later on
Where is the Atrioventricular Node (AV Node) located?
Located directly above the right ventricle in the interatrial septa, the wall of cardiac muscle between the atria
Describe the Krebs Cycle location, substrates and products, general features of the pathway.
Location: matrix of mitochondria. Acetyl CoA feeds into the cycle. 3 NADH made per acetyl CoA. 1 FADH2 made per acetyl CoA. 1 ATP (GTP) made per acetyl CoA. Coenzyme A is regenerated (during the first step of the cycle).
Electron transport chain and oxidative phosphorylation, substrates and products, general features of the pathway.
Location: the cristae (inner membrane of mitochondria). Input NADH Proton gradient *The electron transport chain (ETC) is essentially a series of redox reactions, where NADH gets oxidized to NAD+ and O2 gets reduced to H2O. **The series of redox reactions consists of electrons passing from NADH to FMN, to Coenzyme Q, iron-sulfur complexes, and cytochromes (cytochrome b, c and aa3) before finally being used to reduce oxygen. *NADH is highest in energy, while O2 is lowest in energy. When electrons are passed from NADH down a series of proteins and finally to O2, energy is released. *FADH2 is lower in energy than NADH, that's why it releases less energy when it gets oxidized. *FADH2 skips FMN and passes its electrons to Coenzyme Q. *The energy released from these reactions generates a proton gradient, which drives ATP synthase to make ATP. This is called oxidative phosphorylation. *Proton gradient: The energy released from passing electrons down the ETC is used to pump protons into the intermembrane space of the mitochondria. *H+ concentration is very high in the intermembrane space (higher than those in the matrix). Thus, this establishes an electrochemical gradient called the proton gradient. *H+ wants to migrate down the proton gradient (from the intermembrane space back into the matrix), but it can only do this by going through the ATP synthase. *Like a water mill, ATP synthase harnesses the energy of the falling protons to convert ADP into ATP.
Describe the shape and composition of long bones:
Long bones have s shaft that is curved for strength, they are composed of compact and spongy bone. They are arm, leg, finger and toe bones
Smooth muscle contractions are ____ and ____ than skeletal muscle contractions>
Longer and slower
Describe how and why the Lac Operon is activated:
Low glucose levels lead to high cAMP levels. cAMP binds and activates a catabolite activator protein (CAP). The activated cap protein binds to a cap binding site upstream and adjacent to the promoter region for lac operon. This activates the promoter and allows for the trc and translation of the 3 proteins of the lac operon.
The _____ pH of the stomach denatures the proteins and helps kill ingested bacteria. A full stomach as a pH of ___.
Low; 2
Heavy exercise causes what?
Lowered blood pH Raised CO₂ tension Increased blood temperature Increased carboxyhemoglobin (HbCO₂)
The pathway to the blood takes excess fluid through ____ nodes, which are well prepared to elicit an immune response if necessary.
Lymph Nodes: - the lymphatic system is an integral part of the immune system, and a secondary fluid circulation system.
Throughout the lymphatic system are many ______ containing large quantities of _____.
Lymph nodes; lymphocytes
The ____ system collects excess interstitial fluid and returns it to the blood. Describe it:
Lymphatic System: - it is made up of a network of vessels that carry a clear fluid called lymph - lymph travels throughout this one-way open system always towards the heart - Lymphoid tissue is found in many organs, particularly the lymph nodes
True or False: Enzymes can be specific enough to distinguish between stereoisomers
True
How are lymphocytes created?
Mammalian stem cells differentiate into several kinds of blood cell within the bone marrow.[4] This process is called haematopoiesis. All lymphocytes originate, during this process, from a common lymphoid progenitor before differentiating into their distinct lymphocyte types. The differentiation of lymphocytes follows various pathways in a hierarchical fashion as well as in a more plastic fashion. The formation of lymphocytes is known as lymphopoiesis. - B cells mature into B lymphocytes in the bone marrow, while T cells migrate to and mature in a distinct organ, called the thymus. - Following maturation, the lymphocytes enter the circulation and peripheral lymphoid organs (e.g. the spleen and lymph nodes) where they survey for invading pathogens and/or tumor cells.
What are Mast cells and what do they do?
Mast cell are involved in wound healing, defence against pathogens, and involved in the allergic response. - they also release histamine - they can cause anaphylaxis or anaphylactic shock
What are the identification techniques to finding an mitochondrial inheritance pattern?
Maternal inheritance Affected male cannot pass trait, and unaffected female cannot have affected children
____ arteries constrict enough under sympathetic stimulation to reroute blood.
Medium
MITOSIS OR MEIOSIS: daughter cell different from parent cell
Meiosis
What follows Meiosis 1?
Meiosis 2, which proceeds with prophase 2, metaphase 2, anaphase 2 and telophase 2. - This round of equational division appears much like mitosis and all the final products are haploid gametes with 23 chromosomes.
What is Meiosis?
Meiosis is a double nuclear division that produces 4 haploid gametes (germ cells) from a single diploid germ cell. - Meiosis is the process of reductive cell division - Only the spermatogonium and oogonium undergo meiosis. - all other cell are somatic and undergo Mitosis only. - Meiosis consists of 2 rounds of division: Meiosis 1 is reductional division and Meiosis 2 is equational division.
What happens to the Memory B cells after the infection is taken care of?
Memory B cells will proliferate and remain in the body - In the case of re-infection, each of these cells can be called upon to synthesize antibodies, resulting in a faster acting and more potent affect called the Secondary response.
____ T cells function the same as ____ B cells. They stay in the bloodstream to elicit more immediate and potent immune responses upon secondary infection.
Memory T cells
What are the important biological reactions catalyzed by enzymes?
Metabolism, DNA synthesis, RNA synthesis, protein synthesis, and digestion.
Since capillaries are found close to all cells in the body, they undergo a unique form of fluid exchange called?
Microcirculation: Microcirculation is the delivery of fresh blood to the smallest blood vessels, present in the vasculature embedded within organ tissues. - The vessels on the arterial side of the microcirculation are called the arterioles, which are well innervated, are surrounded by smooth muscle cells, and are 10-100 µm in diameter. Arterioles carry the blood to the capillaries, which are not innervated, have no smooth muscle, and are about 5-8 µm in diameter. Blood flows out of the capillaries into the venules, which have little smooth muscle and are 10-200 µm. The blood flows from venules into the veins. In addition to these blood vessels, the microcirculation also includes lymphatic capillaries and collecting ducts. The main functions of the microcirculation include the regulation of 1. blood flow and tissue perfusion 2. blood pressure, 3. tissue fluid (swelling or edema), 4. delivery of oxygen and other nutrients and removal of CO2 and other metabolic waste products, and 5. body temperature. The microcirculation also has an important role in inflammation. Most vessels of the microcirculation are lined by flattened cells, the endothelium and many are surrounded by contractile cells the smooth muscle or pericytes. The endothelium provides a smooth surface for the flow of blood and regulates the movement of water and dissolved materials in the plasma between the blood and the tissues. The endothelium also produce molecules that discourage the blood from clotting unless there is a leak. The smooth muscle cells can contract and decrease the size of the arterioles and thereby regulate blood flow and blood pressure.
What is the major difference in the functions of microtubules and microfilaments?
Microfilaments (composition); role in cleavage and contractility . Microtubules (composition); role in support and transport)
What is the mitotic metaphase?
Middle (Chromosomes line up in the middle)
What is a missense mutation?
Missense Mutation: a bp mutation that occurs in the amino acid coding sequence of a gene. It may or may not alter the amino acid sequence of a protein and it may or may not have serious effects on the function of the protein.
Since slow twitch muscle fibres account for most of the workload in an endurance event, what organelle is most likely more abundant in slow twitch muscle fibres than in fast twitch?
Mitochondria
Lodged between myofibrils are ____ and many ____.
Mitochondria and many nuclei, skeletal muscle is multinucleated
What is lodged between the many myofibrils?
Mitochondria and many nuclei... Skeletal muscle is multi-nucleated
MITOSIS OR MEIOSIS: 2 daughter cells
Mitosis
MITOSIS OR MEIOSIS: diploid (2n) daughter cells
Mitosis
What is Mitosis?
Mitosis is somatic nuclear division without genetic change. - Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly equal shares of these cellular components
What are the agranular leukocytes?
Monocytes, lymphocytes, and megakaryocytes
Where are the old RBCs disposed of?
Most of them burst in the spleen or liver after 120 days
How does myosin generate force in skeletal muscle?
Multiple myosin II molecules generate force in skeletal muscle through a power stroke mechanism fuelled by the energy released from ATP hydrolysis. The power stroke occurs at the release of phosphate from the myosin molecule after the ATP hydrolysis while myosin is tightly bound to actin. The effect of this release is a conformational change in the molecule that pulls against the actin. The release of the ADP molecule and binding of a new ATP molecule will release myosin from actin. ATP hydrolysis within the myosin will cause it to bind to actin again to repeat the cycle. The combined effect of the myriad power strokes causes the muscle to contract.
Muscle fibres/cells are bound together to form a muscle fasciculus and many muscle fasciculi are wrapped together to form a ____.
Muscle
Muscle contraction occurs when ____ globular heads crawl along an ____ filament in a five-stage cycle.
Muscle contraction occurs when myosin globular heads crawl along an actin filament in a five-stage cycle.
What is the difference in motor units between muscles requiring intricate movements vs muscles that require lots of force?
Muscles requiring intricate movements, like those in the fingers, have smaller motor units, whereas muscles requiring greater force, such as those in the back, have larger motor units.
Why does muscle have a striated appearance?
Myofibrils are positioned end to end
Why does muscle have a striated appearance?
Myofibrils are positioned end to end to form the myofibril, giving it the striated appearance.
What are nails?
Nails are keratinized cells as well.
What are natural killer cells and what do they do?
Natural Killer cells are a special type of cytotoxic lymphocyte, they play a major role in the refection of tumours and cells infected by viruses. - NK cells can attack virtually any infected cell, even if it has not yet been marked for destruction by the immune system
Which occurs more frequently, positive or negative feedback?
Negative
Normally, an enzyme governs just one reaction in a series of reactions. If one of the products downstream in a reaction series comes back and inhibits the enzymatic activity in an early reaction, the phenomenon is called _________
Negative feedback
Which filaments contract during muscular contraction?
Neither the thin nor the thick filaments contract, instead, the proportion of myosin and actin that overlap increases.
If there is no change in protein function, the mutation is called a ____ _____, and if the amino acid is not changed, it is called a ___ ____.
Neutral mutation; silent mutation
What is the leukocyte composition of the blood?
Neutrophils 62% Lymphocytes 30% Monocytes 5.3% Eosinophils 2.3% Basophils 0.4%
Do T lymphocytes make free antibodies?
Never
Do prokaryotes have a nucleus?
No
How does adult skeletal muscle create new muscle cells if at all?
No, instead, a number of changes occur over time as the muscles are exposed to forceful, repetitive contractions
Does RNA poly contain a proofreading mechanism?
No, therefore the rate of errors for trc is higher than for replication
Are errors in RNA transmitted to offspring?
No, they are only used to make proteins and these are not transmitted to progeny. these errors are not generally harmful
Do enzymes affect both thermodynamics and kinetics in a reaction?
No, they only affect kinetics.
Can a person with Type A blood donate to a person with Type B blood or vice versa?
No. A person with Type A blood with produce B antibodies and a person with B blood will produce A antibodies
Do all muscles fibres of a single muscle all contract at once?
No. Instead, from 2 to 2000 fibres spread throughout the muscle are innervated by a single neuron called a motor unit.
What is it called if the sister chromatids are unable to separate to opposite ends of the cell during anaphase of mitosis?
Non-disjunction is the failure of chromosome pairs to separate properly during meiosis stage 1 or stage 2, specifically in the anaphase. This could arise from a failure of homologous chromosomes to separate in meiosis I, or the failure of sister chromatids to separate during meiosis II or mitosis. The result of this error is a cell with an imbalance of chromosomes. Such a cell is said to be aneuploid. Loss of a single chromosome (2n-1), in which the daughter cell(s) with the defect will have one chromosome missing from one of its pairs, is referred to as a monosomy. Gaining a single chromosome, in which the daughter cell(s) with the defect will have one chromosome in addition to its pairs is referred to as a trisomy.
Is nondisjunction more or less severe in mitosis or meiosis?
Nondisjunction in meiosis is more severe because the genetic info is passed on to the offspring.
What happens if during anaphase 1 or 2, the centromere of any chromosome does not split?
Nondisjunction: - as a result of primary nondisjunction, during anaphase 1, one of the cells will have 2 extra chromatids (a complete extra chromosome) and the other will be missing a chromosome. - the extra chromosome will typically line up along the metaphase plate and act normally in Meiosis 2. - Nondisjunction in 2 will result in one cell having one extra chromatid and one cell lacking one chromatid.
Which technique is used to detect RNA fragments?
Northern Blot
Non-competitive inhibition does what to the amount of substrate needed to achieve maximum rate of catalysis
Nothing
Enzymes do what to Delta G?
Nothing.
Eight histones wrapped in DNA form a _____?
Nucleosome
Which animal cells have 2 membranes surrounding?
Nucleus and mitochondria
Nitrogen fixation
N₂ -> NH₃
Describe test crossing
Ok, so you have something with dominant phenotype. It could either be Aa or AA. To find out, you cross it with the homozygous recessive aa. If Aa, half the offspring will express the recessive phenotype. If AA, no offspring will express the recessive phenotype.
What is the SRC a classic example of
Oncogenes
Proto-oncogens, genes that stimulate normal growth in human cells, can be converted to _________, via mutagens or random mutations.
Oncogenes; genes that cause cancer
How many nuclei does each cardiac muscle cell contain?
One
What is one important function of plasma proteins?
One important function of plasma proteins is to act as a source of amino acids for tissue protein replacement.
Describe how DNA polymerase proofreads the newly synthesized strand.
One of the subunits of DNA poly is an exonuclease, it automatically proofreads each new strand, and makes repairs when it discovers any mismatched nucleotides.
Where do DNA nucleotides differ from each other?
Only in their nitrogenous bases.
When an lactose induce trc of the lac operon?
Only when glucose is not present.
Bone forming ______ differentiate from fibroblasts of the perichondrium.
Osteoblasts
What do osteoblasts differentiate into after they are enveloped by the matrix?
Osteoblasts differentiate into osteocytes
____ secrete collagen and organic compounds upon which bone is formed.
Osteoblasts: - they are incapable of mitosis - as osteoblasts release matrix materials around themselves, they become enveloped by the matrix and then differentiates into osteocytes.
______ resorb bone matrix, releasing minerals, such as calcium, back into the blood.
Osteoclasts: - osteoclasts are believed to develop from the white blood cells called monocytes.
______ resorb bone matrix, releasing minerals, such as calcium, back into the blood. Where are these cells developed from?
Osteoclasts: - osteoclasts are believed to develop from the white blood cells called monocytes.
Which cell arises from the same stem cell in the bone marrow as an erythrocyte?
Osteoclasts: they differentiate from phagocytic blood cells and all blood cells differentiate from the same precursor!
How do osteocytes connect to other osteocytes?
Osteocytes make contact with the cytoplasmic processes of their counterparts via a network of small transverse canals, or canaliculi.
_____ are also incapable of mitosis. They exchange nutrients and waste materials with the blood.
Osteocytes: - a star shaped cell, is the most commonly found cell in mature bone, and can live as long as the organism itself. - they do not divide, and they are derived from osteoprogenitors, some of which differentiate into active osteoblasts.[1] In mature bone, osteocytes and their processes reside inside spaces called lacunae and canaliculi, respectively.[1] Cells contain a nucleus and a thin ring of cytoplasm. When osteoblasts become trapped in the matrix they secrete, they become osteocytes. Osteocytes are networked to each other via long cytoplasmic extensions that occupy tiny canals called canaliculi, which are used for exchange of nutrients and waste through gap junctions. The space that an osteocyte occupies is called a lacuna (Latin for a pit).
_____ are also incapable of mitosis. They exchange nutrients and waste materials with the blood.
Osteocytes: - a star shaped cell, is the most commonly found cell in mature bone, and can live as long as the organism itself. - they do not divide, and they are derived from osteoprogenitors, some of which differentiate into active osteoblasts.[1] Osteocytes are networked to each other via long cytoplasmic extensions that occupy tiny canals called canaliculi, which are used for exchange of nutrients and waste through gap junctions. The space that an osteocyte occupies is called a lacuna (Latin for a pit).
parathyroid hormone (peptide)
PTH
Lipase
Pancreatic enzyme necessary to degrade fats, specifically triglycerides. Degrades it into fatty acids and monoglycerides.
Which hormone stimulates osteoclast activity?
Parathyroid Hormone
Explain the concepts of parental, F1, and F2 generations
Parental generation = P = generation of the parent. On a pedigree, the is the row that represents the parents F1 generation = Filial 1 = children. On a pedigree, this is the row below the parents, and represents the children of the parents. F2 generation = Filial 2 = grandchildren. On a pedigree, this is the row below the F1, and represents the children of the F1 and grandchildren of the parents.
What are the partial pressures of Oxygen and carbon dioxide in the lungs, and what roles do these partial pressures play?
Partial pressure of Oxygen is 110mmHg and Carbon Dioxide is 40mmHg. Thus, under these pressures, oxygen diffuses into the capillaries of the lungs and carbon dioxide diffuses from the capillaries to the alveoli of the lungs. Thus, CO₂ is exhaled out.
Define Diastole:
Period of time after systole, when the heart fills with blood. - lowest blood pressure due to no blood being pumped out of heart. - Ventricular diastole is the period during which the ventricles are relaxing, while atrial diastole is the period during which the atria are relaxing. - occurs during relaxation of the whole heart and then contraction of the atria to fill the ventricles.
Peripheral tissue has a ____ shifted curve while the lungs have a ____ shifted curve.
Peripheral tissue has a right shifted curve while the lungs have a left shifted curve.
Why does skeletal muscle NOT contribute to peristalsis?
Peristalsis is a function of smooth muscle only and has nothing to do with skeletal muscle.
What is the difference between a phenotype and a genotype?
Phenotype: what is observed. For example, height, color, whether the organism exhibits a trait. Genotype: the genetic make up. For example, homozygous dominant (TT), heterozygous (Tt), homozygous recessive (tt)
What is depleted first in the body of an athlete performing maximal exercise?
Phosphocreatine
What kind of bonds hold nucleotides together?
Phosphodiester bonds between the phosphate group of one nucleotide and the 3rd carbon of the pentose of the other nucleotide forming large strands
What are the cell types that are derived from B-lymphocytes?
Plasma and memory cells
Describe what plasma is:
Plasma contains the matrix of blood, which includes water, ions, urea, ammonia, proteins, and other organic and inorganic compounds.
Mutation of a gene alters development of heart, bone, and inner ear. What is this an example of?
Pleiotropism
A _____ ______ is a mutation that changes a single base pair of NTs in a double strand of DNA.
Point Mutation
What is the prophase of mitosis?
Prepare (condense chromatin into chromosomes, break down nuclear membrane, assemble mitotic spindle, centriole pairs move toward opposite poles of the cell)
What is the cell called after its has undergone replication in the S phase of Interphase?
Primary Spermatocyte or Primary oocyte.
Enzymes derive from what 4 levels?
Primary, secondary, tertiary, quaternary
________ (prokaryotes/eukaryotes) regulate gene expression predominantly at the transcription level (eg. Operons, in which inducers increase transcription, and inhibitors decrease transcription). _______(prokaryotes/eukaryotes) have more regulation at other levels, and can also undergo RNA splicing, which can splice RNA in different ways to make different mRNAs
Prokaryotes, eukaryotes
Differentiate obligate aerobe, obligate anaerobe, and facultative anaerobe
Prokaryotic terms: Obligate aerobe = must have oxygen for growth. Obligate anaerobe = dies when oxygen is present. Facultative anaerobe = doesn't need oxygen for growth, but grows better with oxygen.
What is the primary function of gene regulation in proks and euks?
Proks= to respond to environmental changes Euks= to control the intra- and extracellular environments of the body
When a human female is born, the development of her oocytes is arrested in:
Prophase 1 of Meiosis.
During which phase of meiosis does genetic recombination occur?
Prophase 1, where crossing over occurs
What is the order of Meiosis?
Prophase 1→ Metaphase 1→ Anaphase 1→ Telophase 1→ Prophase 2→ Metaphase 2→ Anaphase 2→ Telophase 2
What is the mitotic telophase?
Prophase in reverse = de-condense chromosomes, re-form nuclear membrane, break down mitotic spindle.
What are the 4 stages of Mitosis?
Prophase, Metaphase, Anaphase, Telophase
Almost all enzymes in your body is made of what?
Protein
An important function of the stomach is to begin ______ with the enzyme _____.
Protein digestion; pepsin
When and how does protein folding occur? What determines the folding conformation of the protein?
Protein folding begins while the protein is still being translated. The amino acid sequence determines the folding conformation and the folding process is assisted by proteins called chaperones.
cytochromes
Proteins which require a prosthetic heme group in order to function.
What are two important clotting factors?
Prothrombin and fibrogen
Describe the Pulmonary Circulation of the blood:
Pulmonary Circulation: is the half portion of the cardiovascular system which carries oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated (oxygen-rich) blood back to the heart. From the right atrium (end of systemic circulation), blood is squeezed down through the tricuspid valve and into the right ventricle. The right ventricle pumps blood up through the pulmonary valve and into the pulmonary arteries. The pulmonary arteries carry the deoxygenated blood to the arterioles and capillaries of the lungs where they become oxygenated. From the capillaries of the lungs, blood collects in the venules, then in veins, and finally in the pulmonary veins leading back to the left atrium of the heart. From the left atrium, the blood passes down through the Mitral valve and into the left ventricle.
Deoxygenated blood leaves the heart to go to the lungs via the ___ ___.
Pulmonary artery
Oxygenated blood from the lungs enters the heart via the _____ ____.
Pulmonary vein
What can be done in times of CO poisoning?
Pure oxygen is used in order to displace the CO from the hemoglobin
Dimers, trimers, tetramers, and oligomers are examples of what enzyme structure?
Quaternary
Which animal cells have only 1 membrane surrounding
RER, SER, Golgi, lysosomes, peroxisomes
Which protein recognizes the promoter in transcription of a gene?
RNA poly
Which strand does RNA poly transcribe and which strand does it read?
RNA poly unzips the DNA double helix and creates the trc bubble. Then RNA poly transcribes the template or antisense strand by reading it from the 3'-5' direction, making a new strand from the 5' to 3' direction. The new strand created by RNA poly is called the primary rna transcript, containing both exons and introns.
What are the three mRNA modifications?
RNA splicing Alternate splicing 5' capping and 3' poly-A tail
What is RNA Splicing?
RNA splicing: sequences called introns are cut out, sequences called exons are kept and and spliced (joined) together.
Describe a red blood cell:
Red Blood Cells, or erythrocytes, contain the protein hemoglobin which is capable of binding and transporting oxygen.
The diameter of a capillary is equal to that of a single _____ blood cell
Red blood cell
Why is red muscle capable of longer periods of contraction?
Red muscle has large myoglobin reserves along with high amounts of mitochondria.
The net result of the proximal tubule is to?
Reduce the amount of filtrate in the nephron while changing the solute composition without changing the osmolarity
endocrine glands
Release hormones directly into body fluids
Amylopectin
Resembles glycogen but has a different branching structure
Which technique is used to identify individuals as opposed to identifying specific genes?
Restriction fragment length polymorphisms: (RFLP) - the DNA fingerprints used to identify criminals in court
Describe what a cosubstrate does. What is an example of a cosubstrate?
Reversibly bind to a specific enzyme and transfer some chemical group to another substrate. The cosubstrate is then reverted to its original form by another enzymatic reaction. ATP
Individuals having genotypes that code for non-functional products of the Rh gene are said to be ?
Rh-negative; - thus, all others are Rh-positive
What does rRNA do?
Ribosomal RNA combines with proteins to form ribosomes, the cellular complexes that direct the synthesis of proteins. Ribosomal ribonucleic acid (rRNA) is the RNA component of the ribosome, the cell structure that is the site of protein synthesis in all living cells. Ribosomal RNA provides a mechanism for decoding mRNA into amino acids and interacts with tRNAs during translation by providing peptidyl transferase activity. The tRNAs bring the necessary amino acids corresponding to the appropriate mRNA codon. rRNA is synthesized in the nucleolus
What is the function of the nucleolus
Ribosome factory. Site of transcription of rRNA by RNA pol I
The oxygen dissociation curve shifts ____ in tissues where Hb should unload bound oxygen.
Right
What are single nucleotide polymorphisms?
SNPs: is a DNA sequence variation occurring when a single nucleotide — A, T, C or G — in the genome (or other shared sequence) differs between members of a biological species or paired chromosomes in an individual. For example, two sequenced DNA fragments from different individuals, AAGCCTA to AAGCTTA, contain a difference in a single nucleotide. In this case we say that there are two alleles: C and T. Almost all common SNPs have only two alleles - the genome of one human differs from the genome of another at about 1 nucleotide in every 1000, these are SNPs.
What is the smallest functional unit of skeletal muscle?
Sarcomere: - a sarcomere is composed of many strands of two protein filaments, the thick and the thin filament, laid side by side to form a cylindrical segment. - the sarcomere is composed of interdigitated strands of thick myosin and thin actin filaments. - is the basic unit of a muscle. Muscles are composed of tubular muscle cells (myocytes or myofibers). Muscle cells are composed of tubular myofibrils. Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands. Sarcomeres are composed of long, fibrous proteins that slide past each other when the muscles contract and relax. Two of the important proteins are myosin, which forms the thick filament, and actin, which forms the thin filament. Myosin has a long, fibrous tail and a globular head, which binds to actin. The myosin head also binds to ATP, which is the source of energy for muscle movement. Myosin can only bind to actin when the binding sites on actin are exposed by calcium ions. Actin molecules are bound to the Z line, which forms the borders of the sarcomere. Other bands appear when the sarcomere is relaxed.[1] A muscle cell from a biceps may contain 100,000 sarcomeres.[2] The myofibrils of smooth muscle cells are not arranged into sarcomeres.
Secretin
Secreted by the Duodenum in the small intestine and stimulates the pancreas to produce bicarbonate, which neutralizes the acidic chyme in the small intestine
Describe Anaphase 1 of Meiosis:
Separates homologues from their parents, chromosomal migration
What is the electron transport chain?
Series of proteins, including cytochromes with heme, in the inner membrane of the mitochondria
What is plasma called once the clotting factor fibrinogen has been removed?
Serum
Describe the shape and composition of short bones:
Short bones are cuboidal. - they are ankle and wrist bones.
Since microtubules are found in cilia, what might a problem in microtubule production result in?
Since microtubules are part of cilia and cilia exist in the respiratory tract, fallopian tubes and ependymal cells of the spinal cord, a problem in microtubule production may result in a problem breathing, fertility or circulation of CSF.
Explain how muscle attaches one bone to another:
Skeletal muscle connects one bone to another. The muscle does not attach directly to the bone, but instead is attached via a tendon. - Ligaments connect bone to other bone - Typically, a muscle stretches across a joint - The muscle origin is on the larger bone, which remains relatively stationary, and its insertion is on the smaller bone, which moves relative to the larger bone upon contraction of the muscle.
Describe the protein that causes slow twitch type I muscle fibres red?
Slow twitch type I muscle fibres are red from large amounts of myoglobin. - myoglobin is an oxygen storing protein similar to hemoglobin, but having only one protein subunit. - myoglobin stores oxygen in muscle cells.
Do smooth muscle cells contain thick and thin filaments? and if so, are they organized into sarcomeres?
Smooth muscle cells do contain thick and thin filaments but they are not organized into sarcomeres. Smooth muscle cells also contain intermediate filaments, which are attached to dense bodies spread throughout the cell.
Does smooth muscle require calcium to contract and if so why?
Smooth muscle contain thin and thick filaments (actin and myosin), thus it does require calcium to contract.
Smooth muscle is mainly ______, so it is innervated by the ____ NS.
Smooth muscle is mainly involuntary, so it is innervated by the autonomic NS.
What types of stimuli does smooth muscle respond to?
Smooth muscle responds to neural stimuli, hormones, changes in pH, O₂ and CO₂ levels, temperature, and ion concentrations
Describe the differences between prokaryotes and eukaryotes in regards to regulation at the translation level
Some mRNA gets translated more. In prokaryotes, mRNAs with better Shine-Dalgarno sequence are translated more. In eukaryotes, translation regulation can involve adding more polyAs to mRNA (longer mRNA life time), modulating the translation machinary (phosphorylation of initiation factors), or storing mRNAs to be translated at a later time (mRNA masking).
How does bone also serve as a storage site for Ca²⁺ and HPO₄²⁻?
Some of the body's Ca²⁺ exists in bone in the form of slightly soluble calcium salts such as CaHPO₄. It is these salts that buffer the plasma Ca²⁺ levels. Thus, bone acts as a storage site for Ca²⁺ and HPO₄²⁻.
What technique is used to to identify target fragments of known DNA sequence in a large population of DNA?
Southern Blot
What type of linkages are found in: Starch: Glycogen: Cellulose:
Starch: alpha (1-4) Glycogen: alpha (1-4), (1-6) Cellulose: beta(1-4)
Where are the Keratinocytes produced and what happens to them as they rise to the top of the epidermis?
Stem cells in the deepest layer of the epidermis continually divide to produce keratinocytes and other cells. - Keratinocytes are pushed to the top layer - as they rise, they accumulate keratin and die, losing their cytoplasm, nucleus, and other organelles. - When the cell reaches the outermost layer of the skin, they slough off of the body. - this process takes 2-4 weeks.
ETC: Step 1: Step 2: Step 3: Step 4: What is this process called
Step 1: The first protein complex in the series oxidizes NADH by accepting its high energy electons Step 2: Electrons are passed down the protein series and accepted by O2 to form water Step 3: As electrons are passed along, protons are pumped into the intermembrane space for each NADH, establishing a proton gradient called the proton-motive force Step 4: the proton-motive force propels protons through ATP synthase to make ATP. Oxidative phosphorylation
What is the major function of triacylglycerols?
Store metabolic energy, provide thermal insulation, and padding
Main role of stomach in digestion?
Stores food and releases small amounts at a time to be digested and absorbed by intestines.
Why would cardiac output not be dependent on stroke volume differences between the right and left ventricles?
Stroke volume of the ventricles must be the same or we'd have a never ending back-log of blood in one or the other circulations, ending with the faster circulation running dry. Thus, both halves of the circulation must pump the same quantity of blood with each stroke
Collagen is a ____ protein.
Structural
What are synergistic muscles?
Synergistic muscles assist the agonist by stabilizing the origin bone or by positioning the insertion bone during the movement. In this way skeletal muscles allow for movement and posture.
What are synergistic muscles?
Synergistic muscles assist the agonist by stabilizing the origin bone or by positioning the insertion bone during the movement. In this way, skeletal muscle allows for posture and movement.
What is the purpose of the synovial fluid within synovial joint capsules? What type of cells do synovial joints contain?
Synovial fluid provides lubrication and nourishment to the cartilage. - The synovial fluid contains phagocytotic cells that remove microbes and particles which result from wear and tear from joint movement.
What is the purpose of the synovial fluid within synovial joint capsules?
Synovial fluid provides lubrication and nourishment to the cartilage. - The synovial fluid contains phagocytotic cells that remove microbes and particles which result from wear and tear from joint movement. - Synovial joints allow for a wide range of movement.
______ joints are not bound by the intervening cartilage. Instead, they are separated by a capsule filled with _____ fluid.
Synovial joints are not bound by the intervening cartilage. Instead, they are separated by a capsule filled with synovial fluid.
What is the circulatory path of the blood? Describe the systemic circulatory part:
Systemic: the part of the cardiovascular system which carries oxygenated blood away from the heart to the body, and returns deoxygenated blood back to the heart. Beginning with the left ventricle, blood up through the aortic valve, through the aorta. From the aorta, branch many smaller arteries, which themselves branch into smaller arterioles, which branch into still smaller capillaries. Blood from the capillaries collected into venules, which themselves collect into larger veins, which collect again into the superior and inferior vena cava. The vena cava empty into the Right Atrium of the heart.
____ is "peak presure" in the arteries, which occurs near the end of the cardiac cycle when the ventricles are contracting.
Systolic pressure= peak arterial pressure
Type 1 diabetes is a
T cell-mediated autoimmune disease (p. 85) involving destruction of the insulin-secreting β cells in the pancreatic islets which takes place over many years
What are T Lymphocytes?
T cells or T lymphocytes belong to a group of white blood cells known as lymphocytes, and play a central role in cell-mediated immunity. They can be distinguished from other lymphocytes, such as B cells and natural killer cells (NK cells), by the presence of a T cell receptor (TCR) on the cell surface. They are called T cells because they mature in the thymus. There are several subsets of T cells, each with a distinct function.
What do T-Tubules allow for?
T- Tubules allow for a uniform contraction of the muscle by allowing the action potential to spread through the muscle cell more rapidly. - A T-tubule (or transverse tubule) is a deep invagination of the sarcolemma, which is the plasma membrane, only found in skeletal and cardiac muscle cells. These invaginations allow depolarization of the membrane to quickly penetrate to the interior of the cell.
Through which tunnels does an AP move deep into the muscle cell?
T- tubules
What are the 2 states that hemoglobin can exist in?
T-State: tense state, No oxygen O₂ bound R-State: relaxed state, O₂ is bound
Where do T-cells mature into T-Lymphocytes?
T-cells migrate to and mature in the thymus.
What are T-tubules?
T-tubules are deep invaginations of the sarcolemma, allowing for the spread of an AP.
The tertiary structure refers to what?
The 3 dimensional shape formed when the peptide chain curls and folds
Where is the Bundle of His located?
The Bundle of His is located in the wall separating the ventricles.
How are the Ca²⁺ ions removed from the cytosol after muscle contraction?
The Ca²⁺ ions are removed from the cytosol by extremely efficient calcium pumps via active transport. - requires ATP - the mechanism involves an integral protein of the sarcoplasmic reticulum - it occurs against the concentration gradient - it is rapid and efficient
What happens to the Ca²⁺ ions at the end of each contraction cycle?
The Ca²⁺ is actively pumped back into the sarcoplasmic reticulum.
What is the name of the shaft of a typical long bone?
The Diaphysis
What roles does the Haldane Effect play in oxygen transport?
The Haldane Effect facilitates the transfer of CO₂ from blood to lungs, and from tissues to blood. - Reduced Hb (Hb without oxygen) acts as a blood buffer by accepting protons. - It is the greater capacity of reduced Hb to form carbamino Hb that explains the Haldane Effect.
What is the space between both pleura called?
The Intrapleural space or pleural cavity
How do the Killer T cells or also known as the Cytotoxic T cells kill infected cells?
The Killer/Cytotoxic T cell binds to the antigen-carrying cell and it releases perforin onto the antigen-carrying cell in order to perforate and lyse the infected cell.
Why is it that Killer/Cytotoxic T cells have the ability to attack many cells, unlike a macrophage which can only attack a finite number of cells?
The Killer/Cytotoxic T cells have the ability to attack many cells because they do not phagocytize their victims, they bind to and perforate their victims with perforin.
What is the role of the lymphatic system?
The Lymphatic System recycles the interstitial fluid and monitors the blood for infection. - it also reroutes low soluble fat digestates around the small capillaries of the intestine and into the large veins of the neck.
What role do the Purkinje Fibres play in the heart?
The Purkinje Fibres in the ventricles allow for a more unified and stronger contraction.
Why is the Rh factor such a concern for mothers?
The Rh factor is a concern for mothers who are Rh- and have an Rh+ fetus, where the Rh+ antigen was inherited paternally (from father). - For the first pregnancy, the mother is not exposed to fetal blood until giving birth and problems are rare. - Upon exposure to the child's Rh+ blood, the mother develops and immune response against the Rh+ blood. These develop into Memory anti-Rh+ cells that produce the Rh+ antibodies - therefore, in a second pregnancy, if the fetus is Rh+, it may be attacked by the mother's antibodies, which are small enough to pass the placental barrier. - the problem is life threatening, because the memory anti Rh + antibodies from the mother will cross the placenta and destroy the fetal red blood cells. - this is called Erythroblastosis fetalis
What are the specialized group of cardiac muscle cells called that automatically pace the heart contractions, and where are they located?
The Sinoatrial Node (SA Node) or pace-maker cells, located in the right atrium, are responsible for initiating and spreading an action potential for heart contraction. - these cells are autorhythmic (contracts by themselves at regular intervals), spreading its signals to the surrounding cardiac cells via electrical synapses made from gap junctions.
Which is the most important nerve concerning the heart?
The Vagus nerve, which is parasympathetic, innervates both the heart and the digestive tract. The vagus nerve slows the rate heart contractions at the SA Node and increases digestive activity in the intestines.
The ____ chromosome is very small and carries few genes of importance. All the sex-linked alleles are carried on the ___ chromosome.
The Y chromosome is very small and carries few genes of importance. All the sex-linked alleles are carried on the X chromosome.
________ is one mechanism by which a somatic cell of a multicellular organism can alter its genetic makeup without meiosis.
Transposition
What do the Z band and M line represent within muscle tissue?
The Z band marks the borders of sarcomere units within a myofibril and the M line represents the closest distance that two actin filaments can be relative to one another during contraction.
Describe how the SA Node/Pacemaker cells cause the contractions of the heart and the path of the action potential through the heart:
The action potential generated by the SA node causes both atria to contract so blood can be pumped into the ventricles while the atria is refilled (part of diastole). The AP produced by the SA Node spreads around both atria in order to contract both of them at the same time. - the action potential then spreads to the Atrioventricular Node (AV Node), located directly above the right ventricle. - The AV Node is slower to contract, creating a delay to allow the atria and ventricles to finish filling with blood. - From the AV Node, the action potential spreads into the Bundle of His and branches off into Purkinje Fibres which allow for a unified and strong contraction of the ventricles (systole) - the signal spreads down the atria to squeeze blood from the atria into the ventricles.
Since muscles work in groups, what is the agonist and the antagonist?
The agonist is the muscle responsible for movement, so when it contracts, the antagonist, which is the muscle that opposes the agonist, stretches. - when the antagonist contracts, the bone moves in the opposite direction, stretching the agonist. - an example is the biceps and triceps
What is the purpose of the alveoli?
The alveoli increase overall surface area for gas exchange with the pulmonary capillary beds
What is the amount of a given type of protein within a cell likely to be related to?
The amount of its mRNA transcribed, because mRNA has a short life in the cytosol, and because many different proteins can be transcribed from a single mRNA so there is an amplifying effect.
What happens once antibodies bind to specific antigens?
The antibodies then start a cascade of reactions involving blood proteins, called complement, that cause the cell bearing the antigen to become perforated - the antibodies may also mark the antigen for phagocytosis by macrophages and NK cells - the antibodies may cause the antigenic substances to agglutinate or even precipitate, or, in the case of a toxin, the antibodies may block its chemically active portion.
In which part of the human body is the highest blood pressure found?
The aorta
What is absorption?
The assimilation of the by-products of digestion
What controls the rate of the heart contractions?
The autonomic NS controls these contractions, nut the ANS does NOT initiate these contractions.
What is an Operon?
The bacterial genetic unit usually consisting of the operator, promoter, and genes that contribute to a single prok mRNA. An operon is a functioning unit of genomic DNA containing a cluster of genes under the control of a single regulatory signal or promoter.[1][2] The genes are transcribed together into an mRNA strand and either translated together in the cytoplasm, or undergo trans-splicing to create monocistronic mRNAs that are translated separately, i.e. several strands of mRNA that each encode a single gene product. The result of this is that the genes contained in the operon are either expressed together or not at all. Several genes must be both co-transcribed and co-regulated to define an operon.
How would the body compensate for acidosis (too much acid in the blood)?
The body would increase breathing rate thereby expelling CO₂ and raising the pH of the blood. By expelling CO₂ and H₂O, the body has effectively lowered concentrations of blood H⁺ ions and H₂CO₃, effectively lowering acidity of the blood.
What happens when the antagonist contracts and the agonist stretches?
The bone moves in the opposite direction. - An example of antagonistic muscles are the muscles of the upper arm; the bicep and triceps.
What is respiration?
The exchange of gases between an organism and the external environment. It also refers to the transport of gases within the organism, and the diffusion of gases into and out of the cell.
Describe the G₁ phase:
The cell has just split and begins to grow, producing its own organelles and proteins. - regions of heterochromatin have been unwound and decondensed into euchromatin. - RNA and protein synthesis are very active - Cell growth is assessed at the G₁ checkpoint near the end of G₁. - If conditions are favourable for division, the cell enters S phases, if not, it enters G₀. - The main factor in triggering the beginning of S phase is cell size based upon the ratio of cytoplasm to DNA. - G₁ is normally the longest stage
What role does the cilia within the nasal cavity play?
The cilia moves the mucous and dust back toward the pharynx, so that it may be removed by spitting or swallowing.
Cytochromes get their name from what? What are 2 examples of cytochromes?
The color they add to the cell. Hemoglobin, the cytochromes of the electron transport chain in the inner-membrane of mitochondria.
What does the contraction of skeletal muscle do to lymph and blood vessels?
The contraction of skeletal muscle squeezes blood and lymph vessels aiding circulation
How does contraction of skeletal muscle aid in circulation?
The contraction of skeletal muscles squeezes blood and lymphatic vessels, aiding in the circulation of blood and lymph.
Compare the cross sectional area of capillaries to that of arteries and veins:
The cross sectional area of capillaries is is far greater than that of arteries or veins.
Compare the cross-sectional area of veins and arteries:
The cross-sectional area of veins is about 4 times that of arteries.
What is the dermis?
The dermis is connective tissue derived from the mesodermal cells. The dermis is embedded by blood vessels, nerves, glands and hair follicles. - Collagen and elastic fibres in the dermis provide skin with strength, extensibility, and elasticity.
What type of muscle is the diaphragm and which nerve innervates it?
The diaphragm is skeletal muscle and it is innervated by the phrenic nerve.
Describe the Epidermis:
The epidermis is avascular (no blood vessels) epithelial tissue.
What is the Epidermis?
The epidermis is composed of the outermost layers of cells in the skin, "epi" in Greek meaning "over" or "upon", which together with the dermis forms the cutis. The epidermis is a stratified squamous epithelium, composed of proliferating basal and differentiated suprabasal keratinocytes which acts as the body's major barrier against an inhospitable environment, by preventing pathogens from entering, making the skin a natural barrier to infection. It also regulates the amount of water released from the body into the atmosphere through transepidermal water loss (TEWL).
What role does the epiglottis play?
The epiglottis is the cartilaginous member that prevents food from entering the trachea during swallowing. - when non-gaseous material enters the larynx(voice box), a coughing reflex is triggered forcing the material back out.
Describe what happens to an erythrocyte as it leaves the marrow and travels into the blood.
The erythrocyte loses its nucleus while still in the marrow. - after entering the blood stream as reticulocytes, they lose the rest of their organelles within 1 to 2 days.
What does the force of a contracting muscle depend on?
The force of a contracting muscle depends on number and size of the active motor units, and the frequency of action potentials in each neuron of the motor unit.
What does the Hardy-Weinberg law state? What are his 5 assumptions?
The frequencies of alleles in the gene pool of a population will not change over time, provided that a number of assumptions are true: 1. No mutation 2. No migration 3. No natural selection 4. There is random mating 5. Population is large enough to prevent random drift in allele frequencies
The heme group contains an ___ ___ held in a heterocyclic ring known as a _____.
The heme group contains an iron ion held in a heterocyclic ring known as a porphyrin. - The iron ion is bonded to 4 nitrogen atoms in the centre of the ring, all lying in the same plane, and with the globular subunit through a histidine residue.
How does the body heat itself up if cold or freezing?
The hypothalamus will initiate shivering upon stimulation by receptors in the skin and spinal cord
How does the body heat itself up if cold or freezing?
The hypothalamus, part of the autonomic NS, will initiate shivering upon stimulation by receptors in the skin and spinal cord. SHivering is the rapid contraction of skeletal muscle to warm the body, since contraction of skeletal muscle produces large amounts of heat.
What is the integumentary system?
The integumentary system is the organ system that protects the body from damage, comprising the skin and its appendages (including hair, scales, feathers, hoofs, and nails). The integumentary system has a variety of functions; it may serve to waterproof, cushion, and protect the deeper tissues, excrete wastes, and regulate temperature, and is the attachment site for sensory receptors to detect pain, sensation, pressure, and temperature. In most terrestrial vertebrates with significant exposure to sunlight, the integumentary system also provides for vitamin D synthesis. - the skin, hair, nails, glands and some nerve endings make up the integumentary system, - Hair, nails and some nerves are derivatives of embryonic epidermis.
Through which type of junction do action potentials spread from one cardiomyocyte to the next?
The intercalated discs contain gap junctions through which the the AP spreads from one cardiac cell to the next via electrical synapses.
What part of the heart contracts with the most force and why?
The left ventricle contracts with the most force because it needs to propel the blood through the entire systemic circulation.
What is penetrance?
The likelihood that a person w/ a given genotype will express the expected phenotype
deaminates
The liver takes the excess proteins and _____________ them, which means the nitrogen is removed and the C,H,O is used to make glucose.
Veins and venules are similar to arteries and arterioles except for what main difference?
The lumen of veins and venules is significantly larger. They also have much less smooth muscle wrapped around them.
What surrounds the lungs?
The lungs are surrounded by the visceral pleura and the parietal pleura. - The visceral pleura is directly on the lungs and the parietal pleura is closer to the inside of the body cavity.
Where does the lymphatic system empty in the body?
The lymph system empties into large veins at the thoracic duct and the right lymphatic duct
How do lymph vessels prevent fluid from back-flowing?
The lymph vessels are constructed with intermittent valves, which allow fluid to flow in only one direction.
How would you clone DNA with no introns?
The mRNA produced by the DNA is reversed transcribed using reverse transcriptase, producing complementary DNA or cDNA. Then, by adding DNA poly to the cDNA, we create a double stranded fragment of the desired DNA.
What happens to a macrophage once it has engulfed an antigen marked microbe?
The macrophage will present the antigenic determinant of that microbes antigen on its cell surface for B lymphocyte to find - The macrophage is now known as an APC macrophage or Antigen Presenting Cell Macrophage
What are the ends of a typical long bone composed of?
The metaphysis and epiphysis.
Polymerase Chain Reaction:
The method relies on thermal cycling, consisting of cycles of repeated heating and cooling of the reaction for DNA melting and enzymatic replication of the DNA. Primers (short DNA fragments) containing sequences complementary to the target region along with a DNA polymerase (after which the method is named) are key components to enable selective and repeated amplification. As PCR progresses, the DNA generated is itself used as a template for replication, setting in motion a chain reaction in which the DNA template is exponentially amplified. PCR can be extensively modified to perform a wide array of genetic manipulations. amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence.
What are the mitochondria of cardiac muscle like compared to those of skeletal muscle?
The mitochondria of cardiac muscle are larger and far more numerous.
Allosteric interactions
The modification of the enzyme configuration resulting from the binding of an activator or inhibitor at a specific binding site on the enzumme
Do all muscles fibres of a single muscle all contract at once?
The muscle fibres of a single muscle do not all contract at once. Instead, from 2 to 2000 fibres spread throughout the muscle are innervated by a single neuron. - the neuron and the muscle fibres that it innervates are called a motor unit. - motor units are independent of each other.
What happens in Telophase of Mitosis?
The nuclear membrane reforms followed by the reformation of the nucleolus. - chromosomes decondense and become difficult to see under the light microscope - Cytokinesis continues - Telophase is followed by Interphase (G1, S and G2) and DNA replication.
What role does the parasympathetic vagus nerve play in heart contractions?
The pace of the SA Node is faster than normal heartbeats but the vagus nerve innervates the SA Node, slowing the contractions.
Through which duct does the lymph from the right arm and head enter the blood?
The right lymphatic duct... the rest of the body is drained by the thoracic duct
What is the periosteum?
The periosteum is a fibrous sheath that surrounds the long bones in the body. It is the site of muscle tissue attachment. - Periosteum is a membrane that lines the outer surface of all bones,[1] except at the joints of long bones.[2] Endosteum lines the inner surface of all bones. Periosteum consists of dense irregular connective tissue. Periosteum is divided into an outer "fibrous layer" and inner "cambium layer" (or "osteogenic layer"). The fibrous layer contains fibroblasts, while the cambium layer contains progenitor cells that develop into osteoblasts. These osteoblasts are responsible for increasing the width of a long bone[3] and the overall size of the other bone types. After a bone fracture the progenitor cells develop into osteoblasts and chondroblasts, which are essential to the healing process. As opposed to osseous tissue, periosteum has nociceptive nerve endings, making it very sensitive to manipulation. It also provides nourishment by providing the blood supply. Periosteum is attached to bone by strong collagenous fibers called Sharpey's fibres, which extend to the outer circumferential and interstitial lamellae. It also provides an attachment for muscles and tendons. Periosteum that covers the outer surface of the bones of the skull is known as "pericranium" except when in reference to the layers of the scalp
What role does the pharynx play?
The pharynx or throat functions as a passageway for food and air
What happens to the primary mRNA transcript before it leaves the nucleus?
The primary transcript is cleaved into introns and exons. snRPS or small nuclear ribonucleoproteins form a spliceosome and excise out the introns. The exons are then spliced together to form the single mature mRNA strand that ultimately codes for a polypeptide/protein. Introns remain in the nucleus, exons leave the nucleusto be translated into proteins. Exons of some genes may be spliced together in different orders, allowing them to code for different proteins.
Describe feedback inhibition.
The product of a pathway inhibits the pathway.
Explain what happens if no oxygen is available during glycolysis
The products will go to fermentation. In fermentation pyruvate is converted to ethanol or lactic which is then expelled as waste. The NADH is oxidized back to NAD+ so it can be used in glycolysis
What do the proteoglycans of the ECM do?
The proteoglycans contain hydrated protein and carbohydrate chains, and can be very large. They typically create a gelatinous structure between the cells.
*Reabsorption and secretion mostly occur in?
The proximal tubule of the nephron
Though arteries, for the most part, carry oxygenated blood to the body, which artery carries the most deoxygenated blood in the body and why?
The pulmonary artery contains the most deoxygenated blood in the body because it carries all deoxygenated blood from the heart to the lungs in order for it to be reoxygenated.
What is the major contributor for blood pressure in the blood vessels/veins?
The pumping force of the heart
How is the rate of breathing affected and to what does it respond?
The rate of breathing is affected by central chemoreceptors in the medulla, and peripheral chemoreceptors located in the carotid arteries and aorta. - Both types monitor CO₂ concentration in the blood and increase breathing rate when levels are too high. - Oxygen concentration and pH are mainly monitored by peripheral chemoreceptors.
What would happen in the presence of a carbonic anhydrase inhibitor?
The rate of gas exchange in the lungs would decrease because carbonic anhydrase is a catalyst that would normally increase the rate of the reactions. Since it is inhibited, the rate of its reaction is decreased.
What does the ratio of the muscle fibre type within any given muscle depend on?
The ratio depends upon the contraction requirements of the muscle and upon the genetics of the individual.
What does the sarcolemma do?
The sarcolemma is a modified membrane that wraps several myofibrils together to form a muscle cell or muscle fibre. - many muscle fibres are bound into a fasciculus and many fasciculae make up a single muscle.
Describe how and why the lac operon is repressed:
The second regulatory site of the lac operon is the operator, which is located downstream and adjacent to the promoter. The operator is the binding site for the lac repressor protein. The lac repressor protein is inactivated with high levels of lactose in the cell, allowing for the activation of the lac operon to proceed, however, the lac repressor protein will bind to the operator unless lactose binds to and inactivates the lac repressor protein.
Comparing the primary and secondary immune responses, which is faster and more potent?
The secondary is faster and more potent. - it only takes 5 days to reach its full potential
What is cellular respiration?
The set of metabolic reactions that take place at the cellular level to convert energy from nutrients into ATP.
What happens in Anaphase of Mitosis?
The sister chromatids are split apart from each other at their centromeres, and they move toward opposite ends of the cell. This split is termed DISJUNCTION - Cytokinesis, the actual separation of the cellular cytoplasm due to constriction of microfilaments about the centre of the cell, may commence toward the end of this phase.
Why is a person short of breath during an asthma attack?
The smooth muscle surrounding the bronchioles spasms and constricts, causing the shortness of breath.
Describe Type II B or fast twitch II B muscle fibres:
They have a low myoglobin content, thus they appear white and contract very rapidly. - they contain large amounts of glycogen.
How do the neutrophils enter the damaged or infected tissue?
They slip between endothelial cells of the capillary walls, using an amaeboid-like process called Diapedesis.
What is the thick filament of a sarcomere made of?
The thick filament of the sarcomere is made of the protein myosin. - several long myosin molecules wrap around each other to form one thick filament. Globular heads protrude along both ends of the thick filament. - Myosins comprise a family of ATP-dependent motor proteins and are best known for their role in muscle contraction and their involvement in a wide range of other eukaryotic motility processes. They are responsible for actin-based motility. The term was originally used to describe a group of similar ATPases found in striated and smooth muscle cells.
What is the thin filament of a sarcomere made of?
The thin filament of a sarcomere is composed of a polymer of the globular protein actin.
What is the trachea composed of?
The trachea is composed of ringed cartilage covered by ciliated mucous cells. - the mucous and cilia collect dust and usher it towards the pharynx.
Where is the trachea located?
The trachea is the windpipe and it is located in front of the esophagus
100 people are homozygous for an allele that is implicated in cancer, but only 20 develop cancer. Why could this be?
The trait of cancer development is probably polygenic, so it doesn't display simple patterns of inheritance. It also could be affected by other environmental factors.
What does the binding of the lac repressor to the operator in the absence of lactose prevent?
The trc of the lac genes.
(T=tall, t=short, G=green, g=yellow) If height and color genes were not linked, what ratios of phenotypes would be observed in a cross between a TtGg and a ttgg individual?
The ttgg can only make tg gametes. The TtGg can make four different types of gametes: TG, Tg, tG, and tg. The cross will be 25% tall green, 25% tall yellow, 25% short green, and 25% short yellow
What is the larynx?
The voice box, contains the vocal chords. - The larynx sits behind the epiglottis
If a woman heterozygous for type A blood marries a man who is heterozygous for type B, what are the possible genotypes and blood types of the kids?
The womans genotype: IAi The mans genotype: IBi The children could be IAIB (AB), IAi(A), IBi(B) or ii (O)
How are enzymes denatured?
Their structures are altered by heat and extreme pH levels
For an autosomal gene in a population of 2000 individuals, how many copies of the gene are present in the gene pool?
There are 2 copies of the gene in each of the 2000 people, so 4000
How many layers or strata are there in the epidermis and what are they?
There are 5 layers of the epidermis: - the deepest layer contains the Merkel cells and stem cells. - the stem cells continually divide to produce keratinocytes and other cells. - Keratinocytes are pushed to the top layer - as they rise, they accumulate keratin and die, losing their cytoplasm, nucleus, and other organelles. - the outermost layer of epidermis consists of 25-30 layers of flat, dead cells.
From what and where do the agranular and granular forms derive?
They all derive from pluripotent stem cells (myeloid and lymphoid) in the bone marrow.
In a dehydrated individual, blood levels of vasopressin and aldosterone are likely to be:
They are both likely to be higher. -In severely dehydrated person, blood volume would be low, likely resulting in diminished blood pressure. Aldosterone levels will rise in response to the low blood pressure.
What happens to monocytes once they are deposited into tissues?
They become macrophages where they can live for years.
How do activators or repressors affect gene expression?
They bind to the DNA close to the promoter and either activate or repress the activity of rna poly during trc. Activators bind upstream of promoter, repressors bind downstream
What happens to the neutrophils and macrophages once they engulf necrotic tissue and bacteria?
They die. These dead leukocytes, along with the fluid and necrotic tissue, make up the pus from an infection.
When a blood type is termed negative, as in type B negative, what does it mean?
This means that the person with Type B blood carries the B antigen on the RBC but NOT the Rh factor. - it does not carry A antigen - It does produce A antibodies and Rh antibodies
Increasing the duration of ventricular diastole would serve what purpose?
This would increase the period of time the heart fills with blood, thus would decrease cardiac output and decrease blood pressure
What would permanent sequestering of calcium in the sarcoplasmic reticulum lead to?
This would prevent calcium from leaving the sarcoplasmic reticulum and binding to troponin, which is what causes the conformational change that moves tropomyosin away from the myosin binding sites/active sites on actin filaments. Thus, if no calcium is able to leave the SR and bind troponin, no myosin would be able to bind to the actin active sites and thus there would be no muscle contractions.
Where is the velocity of blood the slowest in the body?
Through the capillaries
How is the platelet membrane designed?
To avoid adherence to healthy endothelium while adhering to injured endothelium.
What is the purpose of the fluid exchange that occurs in the capillaries?
To control for inflammation, blood flow, blood pressure, tissue fluid (edema), gas exchange and body temp.
What is the main role of the respiratory system?
To deliver oxygen to the blood and expel carbon dioxide
What is the function of gap junctions in the intercalated disc of cardiac muscle?
To insure that an AP is spread to all fibres in the muscle network.
The net affect of the distal tubule is?
To lower the filtrate osmolarity.
Why does a cardiac muscle cell remain depolarized much longer than a neuron during an AP?
To precent the initiation of another action potential during contraction of the heart.
What is the role of Red Blood Cells?
To transport/deliver oxygen and remove CO₂
Why is the concentration of free Ca²⁺ ions in the blood the physiologically important form of calcium?
Too much Ca²⁺ results in cellular membrane becoming hypo-excitable producing lethargy, and memory loss; too little produces cramps and convulsions.
The cell cycle can be arrested for many reasons: Name three of them.
Too much genomic mutation/damage causes a cell to arrest in M phase. Contact inhibition Lack of food can also cause growth arrest.
If 20% of the population is heterozygous for an allele Q and 10% is homozygous, what will be the frequency of the allele in the population?
Total number of alleles is 100%. (0.5 x 20%heterozygotes) + 10% homozygotes = 20%
What is viral transduction? Describe the process
Transfer of genetic material by viruses Virus infects cell: host DNA degraded into fragments, viral DNA takes over control. Host DNA fragment gets packed into virus progeny by accident. Virus progeny infects another cell, injects previous host's DNA fragment. Fragment enters cell, find its homologous counterpart, and crossover.
What is a base pair substitution involving a complete switch from from the A-T bp to the G-C bp or vice versa called?
Transition mutation
What are the 2 types of ribosomes upon which translation will occur?
Translation always begins on free floating ribosomes 1) On free floating ribosomes in the cytosol, producing proteins that function in the cytosol. 2) Or ribosomes may attach itself to the rough ER during translation and inject proteins into the ER lumen-- these proteins are destined to become membrane bound proteins of the nuclear envelope, ER, golgi, lysosomes, PM, or to be secreted from the cell.
What is the resulting mutation called when one segment of DNA from one chromosome is inserted into another chromosome?
Translocation
Rough ER's role is the biosynthesis of transmembrane and secreted proteins that are cotranslationally targeted to RER by signal sequence. What goes on in this process? ribosome now on the RER continues making the protein, but snakes it into the lumen. Signal sequence is clipped off
Transmembrane proteins, or proteins that are to be secreted (need RER vesicle) have a signal sequence right at the beginning. When ribosome starts making those proteins, they make the signal sequence first. Signal sequence recruits a signal recognition particle that drags it to the RER.
trypsin (located?) and chymotrypsin released from? function?
Trypsin is located in the brush border -Both are released from pancreas -degrades proteins into small polypeptides
Describe Type II A or fast twitch II A muscle fibres:
Type II A muscle fibres are also red, but they split ATP at a high rate. - Type II A fibres contract rapidly - Type II A fibres are resistant to fatigue but not as resistant as type I fibres
How many nuclei does each cardiac muscle cell contain?
Unlike skeletal muscle, each cardiac muscle cell only contains one nucleus and the cardiac muscle cell is separated from its neighbour via and intercalated disc.
Is Uracil in RNA a purine or pyrimidine?
Uracil is pyrimidine.
During protein metabolism, the liver de-aminates amino acids, forms ___ from ___ in the blood, and synthesizes?
Urea; ammonia -Synthesizes plasma proteins such as fibrinogen, prothrombin, albumin, and most globulins and synthesizes nonessential amino acids
What are the nonpolar amino acids?
VIP Malt Valine, Isoleucine, Proline, Methionine, Alanine, Leucine, Tryptophan, Phenyalanine, and Glycine
In active immunity, production of memory B cells against a particular antigen is conferred by _____.
Vaccination - a second vaccination a few month later is typically needed to cause a secondary response which increases the longevity of immunity for the antigen.
____ always carry blood to the heart; ___ always carry blood away from the heart.
Veins; Arteries
Deoxygenated blood coming from the body enters the heart via the ___ ___.
Vena cava
Through which duct does the lymphatic system connect to the circulatory system?
Via The thoracic duct of the lymphatic system is the largest lymphatic vessel in the body. It is also known as the left lymphatic duct, alimentary duct, chyliferous duct, and Van Hoorne's canal. - It collects most of the lymph in the body (except that from the right arm and the right side of the chest, neck and head, and lower left lobe of the lung, which is collected by the right lymphatic duct) and drains into the systemic (blood) circulation at the left brachiocephalic vein between the left subclavian and left internal jugular veins. - The thoracic duct originates in the abdomen from the confluence of the right and left lumbar trunks and the intestinal trunk, forming a significant pathway upward called the cisterna chyli. It extends vertically in the chest and curves posteriorly to the left carotid artery and left internal jugular vein at the C7 vertebral level to empty into the junction of the left subclavian vein and left jugular vein, below the clavicle, near the shoulders. It traverses the diaphragm at the aortic aperture and ascends the superior and posterior mediastinum between the descending thoracic aorta (to its left) and the azygos vein (to its right).
How does the action potential from the Bundle of His branch out through the ventricular walls?
Via conductive fibres called Purkinje Fibres.
How are nucleotides bound to each other?
Via phosphodiester bonds between the 3rd carbon of one deoxyribose and the 5th carbon of the other creating the sugar-phospahte backbone of a single strand of DNA with a 5'→3' directionality.
How are proteins and large particles that cannot be taken up by the capillaries removed from the interstitium and returned to the blood?
Via the lymphatic system
The outermost layer of the small intestine wall contains finger-like projections called? Function?
Villi -Increase surface area of the intestinal wall allowing for greater digestion and absorption
plus-strand RNA
Virus; "plus-strand" - proteins can be directly translated from the RNA
Is skeletal muscle involuntary or voluntary?
Voluntary
Skeletal muscle is ____ muscle tissue.
Voluntary; wherein it can consciously controlled
What happens to Hb's capacity to hold CO₂ when it is saturated with oxygen?
When Hb is saturated with oxygen, its capacity to hold carbon dioxide is reduced. The Haldane Effect
When does translation end?
When a stop codon is reached in a step called termination. When a stop (or nonsense) codon reaches the A site, proteins known as release factors bind to the A site allowing a water molecule to add to the end of the polypeptide chain. The polypeptide is freed from the tRNA and ribosome, and the ribosome breaks up into its subunits to be used again for another round of protein synthesis later.
What happens when an antibody whose base is bound to a mast cell also binds to an antigen?
When an antibody, whose base is bound to a mast cell, also binds an antigen, the mast cell releases histamine and other chemicals.
When chromatin is condensed and wrapped into nucleosomes, it is called _______, though when chromatin is uncoiled and being transcribed, it is called ______. Chromatin that is permanently coiled is called ______.
When chromatin is condensed and wrapped into nucleosomes, it is called heterochromatin, though when chromatin is uncoiled and being transcribed, it is called euchromatin. Chromatin that is permanently coiled is called constitutive heterochromatin. Heterochromatin is not transcribed.
Describe allosteric regulation
When feedback inhibitors don't resemble the substrates of the enzyme that they inhibit, they bind to the enzyme and cause a conformational change.
Explain linkage
When genes that are located on the same chromosome do not display independent assortment.
What is nondisjunction
When homologous chromosomes in meiosis I fail to separate, or when sister chromatids in meiosis II fail to separate
What is the Quaternary enzyme structure?
When more than one chain is involved.
What is contact inhibition?
When normal epithelial cells stop growing when it gets crowded such that it's touching adjacent cells.
Describe the changes in diaphragm shape as a person breathes.
When relaxed, the diaphragm is dome-shaped. It flattens upon contraction, expanding the chest cavity and creating negative gauge pressure, allowing for the lungs to take in air. - Thus, with negative gauge pressure, atmospheric pressure forces air into the lungs - Upon relaxation of the diaphragm, the chest cavity shrinks, aided by other intercostal muscles and abdominal muscles, and the elasticity of the lungs along with increased pressure in the chest cavity forces the air out of the body
What is the Buffy coat made from?
White blood(leukocytes) cells and platelets
How is the Oxygen dissociation curve affected with an increase in carbon dioxide pressure?
With an increase in CO₂ pressure, the oxygen dissociation curve is shifted to the right. - this indicates a lowering of Hemoglobin's affinity for oxygen. - thus, with increased CO₂, the Hb can not bind O₂ as well.
How is the Oxygen dissociation curve affected with an increase in hydrogen ion concentration?
With an increase in hydrogen ion concentration comes a lowered pH, thus the curve is shifted to the right, thus indicating a lowered affinity for O₂. - This is called the Bohr effect, wherein H⁺ ions bind to Hb, releasing O₂ bound by Hb to the peripheral tissue.
Where does the actual gas exchange occur in the lungs?
Within the alveoli
How does the thymus test T lymphocytes?
Within the thymus, T lymphocytes are tested against self-antigen, or antigen that are found on normal body tissue. If the T lymphocyte binds to a self-antigen, the T lymphocyte will be destroyed to prevent autoimmune diseases If the T lymphocyte does not bind to self-antigens, it is released into the blood and lymphoid tissue after differentiating into Helper, Memory, Suppressor and Killer T cells
What does yellow bone marrow contain?
Yellow bone marrow contains adipose cells for fat storage.
Is cardiac muscle striated like skeletal muscle?
Yes, cardiac muscle is striated like skeletal muscle, which means that cardiac muscle is also composed of sarcomeres.
is there such a thing as double straded RNA viruses and single and double stranded DNA viruses?
Yes.
What is the main difference between overcoming competitive inhibition and overcoming non-competitive inhibition in regards
You can overcome competitive inhibition by providing more substrate. Providing more substrate will not overcome non competitive inhibition, however.
neurotransmitters
___ are capable of excitation or inhibition depending upon the type of receptor in the postsynaptic membrane
prokaryotic
___ flagella is formed from a thin strand of flagellin
eukaryotic, prokaryotic
___ flagella undergo a whip-like action, ___ flagella rotate
What is the net result of fluid exchange by the capillaries?
a 10% loss of fluid to the interstitium, thus to the lymphatic system
kidney
a bean-shaped organ that filters waste from the blood and produces urine
What does DNA poly require to start replication?
a dna primer laid down by Primase
Define Systole:
a force that drives blood out of the heart. Without qualifiers, it usually means the contraction of the left ventricle. When the smaller, upper atria chambers contract in the first phase of systole, they send blood down to the larger, lower ventricle chambers. When the lower chambers are filled and the valves to the atria are closed, the ventricles contract in the second phase, sending blood from the left ventricle to the aorta and body, and from the right ventricle to the lungs. Thus, the atria and ventricles contract in sequence (the atria feeding blood into the ventricles), while the left and right ventricles contract at the same time. - occurs when the ventricles contract and force blood out if the heart. - Highest blood pressure due to blood pumping out of ventricles
What is a gene?
a gene is a stretch of DNA that codes for a trait. In molecular biology, the gene codes for a protein, which acts to bring about a trait.
What are Globulins?
a group of proteins that include antibodies
semipermeable membrane
a membrane that slows diffusion but does not stop it for a particular compound
insulin sensitivity
a person with insulin resistance is said to have decreased insulin sensitivity. The body's cells are not sensitive to insulin, so they resist it and sugar levels are not regulated effectively
What is a promoter?
a promoter is a region of DNA that initiates transcription of a particular gene. Promoters are located near the genes they transcribe, on the same strand and upstream (towards the 5' region of the sense strand). The TSS is part of the promoter, the transcription start point is +1, the first base pair. A TATA box is a promoter
What is a centromere?
a region on the chromosome, can be at the center or close to one of the ends.
What do genes normally code for?
a single polypeptide, mRNA, rRNA, or tRNA
one, or
a single synapse usually releases __ neurotransmitter and is designed to excite ___ to inhibit
globules
a small round particle of a substance
prophage
a type of provirus if host cell is bacterium
Polydipsia
abnormal state of much thirst
hypothermia
abnormally low body temperature
How long does replication in human cells take?
about 8 hours
One function of the large intestine is:
absorb water
What major action of small intestine in digestion?
absorption
diabetic nephropathy
accumulation of damage to glomerulus capillaries due to chronic high blood sugars of diabetes mellitus
integral/intrinsic proteins
amphipathic proteins that traverse the membrane from the inside of the cell to the outside
Capillaries are found close to ____?
all cells of the body
Heat is a denaturing agent that disrupts what force?
all forces
receptors
all hormones act by binding to these proteins
What does the term "gene pool" relate to?
all of the alleles in a population.
If there are 5000 hippos in a population, out of which there are 100 homozygotes of an autosomal allele h and 400 heterozygotes, what is the frequency of the h allele in the population
allele freq= number of copies of a specific allele/total number of copies of the gene There are 5000, so there are 10,000 copies of the gene. There are 100 homozygotes of the h allele, each with 2 copies of it, and 400 heterozygotes with one h allele, for a total of 600 h alleles. 600/10,000 = .06
Bowman's capsule assists in clearing urea from the blood by?
allowing urea to diffuse into a filtrate under filtration pressure
What are examples of secondary enzyme structure?
alpha helices and beta sheets (backbone H-bonding). For RNA, this is base pairing.
Animals eat _____ linkages, but only bacteria break the ____ linkages.
alpha, beta
mRNA produced in bacteria is....
already mature, contains multiple genes and is translated directly into protein.
What is recombination?
also called genetic recombination, is the process that introduces genetic diversity into the gametes during meiosis. There are 2 processes that make up recombination: independent assortment and crossing over.
Proteins are built from a chain of ______ linked by ______, and are therefore called ________
amino acids, peptide bonds, polypeptides
All dietary protein is completely broken down into _____ before ____. Any protein that isn't broken down may cause ____. FOR MCAT-- when you think of proteins, think of?
amino acids; being absorbed into the blood; Allergic reactions. -NITROGEN
Gene mutation:
an alteration in the sequence of DNA nts in a single gene
What is an antigenic determinant that is removed from the antigen called?
an antigenic determinant that is removed from the antigen is called a Hapten
Describe the process of ATP production?
an apparatus called the ATP synthase makes ATP from ADP by utilizing the proton gradient as the driving force. The proton gradient is where the proton H+ concentration is higher in the inter-membrane space than the matrix of the mitochondria
Fermentation
anaerobic respiration. Reduction of pyruvate to ethanol or lactic acid and reduction of NADH to NAD+
What are the acidic amino acids?
aspartic acid and glutemic acid
Describe the generalized phage and viral life cycle
attachment to host, penetration of cell membrane or cell wall, and entry of viral genetic material use of host synthetic mechanism to replicate viral components: Host's ribosomes synthesize the necessary enzymes. Host's ATP provides necessary energy. The host also provides the raw materials such as nucleotides and amino acids. Next is self-assembly and release of new viral particles: The coat proteins and viral genetic material will assemble into viral particles all by themselves.
Why is DNA replication referred to as semidiscontinuous?
because the formation of one strand is continuous while the other strand is fragmented.
For the MCAT, you should know that when the liver mobilizes fat or protein for energy, what happens?
blood acidity increases
When a gene has only 2 alleles, then that's the simple case we're used to seeing. For example, the trait for height in peas is governed by T and t. TT and Tt gives tall plants, and tt gives short ones. When a gene has more than 2 alleles, then that's called multiple alleles. What is an example of this in the circulatory system?
blood type is governed 3 alleles: IA IB and i. Because a cell can only hold 2 of these alleles, the different combinations an individual can have are: Genotype Blood type (phenotype) IAIA or IAi---->A IBIB or IBi---->B IAIB ---->AB ii----->O
nervous system
brain, spinal cord, nerves, neural support cells, eye, ear
What is digestion?
breakdown of food
Proteolysis
breaking down of protein, the breakdown of proteins (from body tissues) into amino acids
Describe catabolism
breaking stuff down for energy
eclipse period
brief period before the first fully formed virion appears
What creates the plateau after depolarization of the cardiac muscle?
by the effects of slow voltage-gated calcium channels, allowing calcium to enter and hold the inside of the membrane at a positive potential difference
What is cDNA?
cDNA is just DNA that is reverse transcribed from mRNA. cDNA lacks introns that would normally be found in eukaryotic DNA. This is beneficial when trying to insert euk DNA into bacterial DNA because bacteria have no way of removing the introns.
How is smooth muscle shaped?
cell is tapered
host
cell that is being infected
goblet cells
cells of the GI tract (and lungs) that secrete mucus to lubricate the intestine and help protect the brush border from mechanical and chemical damage
Chromosomal mutation:
changes to the structure of a chromosome
electrochemical gradient
chemical concentration gradient + electrical gradient; electrochemical gradient for compound X points in the direction that particle X will tend to move.
neurotransmitters
chemicals used for communication in the nervous system
What are fungi walls made of?
chitin
The liver synthesizes bile from
cholesterol and converts carbohydrates and proteins into fat
A common question is what is the difference between chromatin and chromosome. So..if someone asked you this, how would you explain the difference??
chromatin is the "stuff" that chromosomes are made of. If the chromosome is a cotton shirt, then chromatin is cotton
Where is a gene located?
chromosome
The stomach is a very flexible pouch that both mixes and stores food, reducing it to a semifluid mass called ___.
chyme
What is the function of the lysosomes
contain acid hydrolases which digest substances
What is the function of the nucleus
contain and protect DNA, transcription, partial assembly of ribosomes
lysosomes
contain hydrolytic enzymes that digest substances taken in by endocytosis; come from the Golgi
____________ is an important component in many second messenger systems
cyclic AMP
Which amino acids have sulfur?
cysteine and methionine
sympathetic ANS
deals with fight or flight responses; increases heart rate and stroke volume, constricts blood vessels around digestive and excretory systems to increase skeletal blood flow
Muscles cause movement at joints by:
decreasing in length or contracting, thereby bringing the muscle's origin and insertion closer together.
Trypsin and chymotrypsin
degrade proteins into small polypeptides
The AV node:
delays the contraction of the ventricles of the heart
What does mRNA do?
delivers the DNA code for amino acids to the cytosol where the proteins are manufactured. Messenger RNA (mRNA) is a molecule of RNA that encodes a chemical "blueprint" for a protein product. mRNA is transcribed from a DNA template, and carries coding information to the sites of protein synthesis, the ribosomes. In the ribosomes, the mRNA is translated into a polymer of amino acids: a protein. (This process is sometimes referred to as the central dogma of molecular biology
peptide hormones
derived from peptides often include carbohydrate portions manufactured in the rough ER as a preprohormone golgi modifies it released via exoctyosis act through a secondary messenger system because they can't diffuse through the membrane
proteinuria in absence of urinary tract
diabetic nephropathy
The major functions of the large intestine are water absorption and electrolyte absorption. When this function fails what results?
diarrhea
facilitated diffusion
diffusion facilitated by transport or carrier proteins; diffusion must occur down the electro-chemical gradient of all species involved
passive diffusion
diffusion where molecules move through leakage channels across the membrane due to random motion
Any cell that contains homologous pairs is said to be?
diploid
somatic nervous system
division of the PNS designed primarily to respond to the external environment; contains sensory and motor functions; voluntary; motor neurons innervate skeletal muscle
autonomic nervous system
division of the PNS that receives signals from the viscera; motor portion conducts theses signals to smooth muscle, cardiac muscle, and glands; involuntary
Prokaryotes
do not have a membrane bound nucleus; split into Bacteria and Archaea
What is the difference between autosomal dominant and autosomal recessive?
dominant- a single copy of the allele will confer the trait or disease phenotype recessive- two copies of the allele are required for the affected phenotype
When is euchromatin coiled?
during nuclear division
tympanic membrane
ear drum, beginning of the middle ear
gonadal hormones (steroid)
estrogen, progesterone, testosterone
Eukaryotic genes that are being actively transcribed by a cell are found in which regions of DNA?
euchromatin
What is a translation error?
even if the DNA for a gene is perfect, errors during translation can cause expression of a mutant phenotype.
What is a transcription error?
even if the DNA of a gene is perfect, errors during transcription can cause expression of a mutant phenotype.
retroviruses
example of enveloped plus-strand RNA carry reverse transcriptase
hyperaldosteronism
excessive output of aldosterone from the adrenal gland, leading to increased sodium and water retention and loss of potassium
polyuria
excessive urination
Since the SA node is innervated by the vagus nerve, the frequency of self-excitation of the cardiac cells of the SA node is likely to be:
faster than a normal heartbeat because excitation by the vagus nerve decreases the heart rate. - The vagus nerve is a parasympathetic nerve. Heart rate is set by the SA node, and the SA node is innervated by the parasympathetic vagus nerve. - the parasympathetic nerve tonically slows the contractions of the heart to its resting pace.
In a coupled transcription-translation system, regulation by attenuation can occur for the Trp gene: What happens when the cell is full of Trp? What about when the cell is starved for Trp?
full: translation occurs fast because of abundant Trp amino acid. This fast ribosome movement across the transcribing mRNA causes the Trp mRNA transcription to terminate. Because Trp is not needed. starved: translation occurs slower because Trp amino acid is lacking. This slower ribosome movement across the transcribing mRNA causes the Trp mRNA to be made to its completion.
Describe lichens
fungi + algae. Algae provides food, fungi provides water and protection.
Describe mycorhhizae
fungi + plant roots. Plant provides food, fungi provides more absorption surface area.
G cells secrete? Function of this hormone?
gastrin (a large peptide hormone) into the interstitium where it is absorbed in the blood and stimulates parietal cells to make HCl
In genetics, what is leakage?
gene flow from one species to another
What is the difference between a gene and an allele
gene- length of DNA coding for a particular gene product allele- different versions of genes that carry out the genes functions
What are oncogenes?
genes that cause cancer when activated. The product of many oncogenes are involved in speeding up cell division. Before an oncogene is activated, it is a harmless proto-oncogene. Something occurs that changes the proto-oncogene to an oncogene.
pancreatic hormones (peptide)
glucagon and insulin
adrenal cortex hormones (steroid)
glucocorticoids and mineral corticoids
During carbohydrate metabolism, the liver maintains normal blood glucose levels through?
gluconeogenesis, glycogenesis, and storage of glycogen
Which amino acid is not optically active?
glycine
Any cell that does not contain homologues is said to be?
haploid
Chemoautotrophs
have a large environmental impact all known chemoautotrophs are prokaryotes
Archaea
have as much in common with eukaryotes as they do with bacteria; found in extreme environments; cell walls are not made from peptidoglycan
amphiphatic
having both a polar and a nonpolar portion; example: phospholipid bilayer
Other than excreting waste products, such as urea, uric acid, ammonia, and phosphate and maintaining homeostasis of the body fluid volume and solute composition...What do the kidneys also do?
help control plasma pH
There are some traits that are inherited via the mitochondrial genome called mitochondrial traits. These traits are an example of _____
hemizygosity; the individual only has one copy of the chromosome in a diploid organism.
Heterochromatin vs euchromatin
hetero: densely packed chromatin where genes are inaccessible and turned off eu- same as hetero but allow genes to be activated.
What are the basic amino acids?
histidine, lysine, arginine
The sections of DNA that are not in use are wrapped tightly around globular proteins called ______?
histones
What are nuclear pores?
holes in the nuclear envelope where things can pass into and out of the nucleus. Transcription occurs in the nucleus, and those transcribed RNA need to pass out of the nucleus. Things like transcription factors need to pass into the nucleus where they can access the DNA to be transcribed.
In human cells, each chr possesses a partner that codes for the same traits as itself, two such chromosomes are called?
homologues; though the traits are the same, the actual genes may be different.
cholecystokinin
hormone release from small intestine in response to presence of fats, causes contraction of gall bladder and release of bile to small intestine (to aid in digestion of fats)
What do steroids include?
hormones, vitamin D, and cholesterol
endocytotic process
how most viruses that infect eukaryotes are infected
Urea is a denaturing agent that disrupts what force?
hydrogen bonds
organic solvents are denaturing agents that disrupts what force?
hydrophobic forces
What are fungi made out of?
hyphae filaments
Describe tumor suppressors
if the oncogene is the "bad" gene, tumor suppressors are the "good" genes. The product of many tumor suppressors are involved in slowing down or controlling cell division. If something happens that cause the tumor suppressor to no longer function, then the cell becomes cancerous.
chemical synapse, Ca2+, into, postsynaptic, ions
in a ___, small vesicles filled with neurotransmitter rest just inside the presynaptic membrane, which contains a large number of voltage gated __ channels that are activated by the arrival of an action potential; Ca2+ rushes ___ the presynaptic neuron leading to the exocytosis of neurotransmitters into the synaptic cleft which bind to receptor proteins on the __ neuron, and the postsynaptic membrane becomes more permeable to ___
inner, cristae
in mitochondria, the ___ membrane invaginates to form ___
Describe transcription-translation coupling in prokaryotes
in prokaryotes, translation occurs as the mRNA is being transcribed (no RNA processing in prokaryotes).
In which direction does RNA poly move along the DNA strand?
in the 3' to 5' direction, same with DNA poly, building new RNA strand in the 5' to 3' direction
In which direction does DNA poly read the parental DNA strand?
in the 3'→5' direction.
Where is DNA found in animals?
in the nucleus and mitochondrial matrix.
rods, cones
in the retina __ don't distinguish colors, ___ do
Where is the SA Node located?
in the top of the right Atrium
In viruses, what is transformation? Describe the process
incorporation into bacterial genome of DNA fragments from external medium When a bacteria dies, it lyses and spills many DNA fragments into the environment. Another bacteria encounters these DNA fragments, takes them in, and integrates them into its own genome. If the DNA fragments contained an antibiotic resistant gene, then the transformation just made the bacteria antibiotic resista
glucocorticoids
increase blood glucose concentration and have an even greater effect on fat and protein metabolism
peptide hormones secreted by the small intestine after a meal have what effect?
increase blood insulin levels especially in the presence of glucose.
Some carcinogens are direct mitogens. What do mitogens do?
increase mitosis
There are two kidneys and each one is made up of?
inner medulla and an outer cortex
IDDM
insulin-dependent diabetes mellitus-type 1 diabetes, insulin deficiency requiring replacement therapy.
voltage gated sodium channels
integral membrane proteins in neuron that change configuration when voltage is disturbed, allowing sodium to pass through
lower brain
integrates subconscious activities such as the respiratory system, arterial pressure, salivation, emotions, and reaction to pain and pleasure
Define Lymphocytes:
is a type of white blood cell in the vertebrate immune system. - The three major types of lymphocyte are T cells, B cells and natural killer (NK) cells.
In genetics, what is expressivity?
is to what degree a penetrant gene is expressed.
How does the shape gene affect inheritance of the alleles for the color gene
it doesn't (independent assortment)
From the purkinje fibres, how the action potential transmitted from one cardiac muscle to the next?
it is spread through gap junctions from the purkinje fibres from one cardiac muscle to the next.
What role does the coding strand play in trc?
it protects the template strand from degradation.
desmosomes
join two cells at a single point; attach directly to the cytoskeleton of each cell; don't prevent fluid from circulating around the cell
What monitors the filtrate pressure in the distal tubule?
juxtaglomerular apparatus
The oxygen dissociation curve shifts ____ in tissues where Hb should load more oxygen.
left
anterior pitutary
located in the brain beneath the hypothalamus releases peptide hormones
semicircular canals
located in the inner ear; responsible for balance; contain fluid and hair cells; oreinted 90° to each other to detect movement in all directions
Where are the Purkinje Fibres located?
located in the inner ventricular walls of the heart, just beneath the endocardium. These fibers consist of specialized cardiomyocytes that are able to conduct cardiac action potentials more quickly and efficiently than any other cells in the heart. Purkinje fibers allow the heart's conduction system to create synchronized contractions of its ventricles, and are therefore essential for maintaining a consistent heart rhythm.
hair cells
located in the organ of Corti detect movement in the cochlea and tranduce it into neural signals that are sent to the brain
What is the function/location of the nucleolus?
location is a region inside the nucleus. function is to transcribe ribosomal RNA (rRNA).
What is the function of the RER
location of the synthesis/modification of secretory, membrane-bound, and organelle proteins
Explain what happens as the mRNA finishes post transcriptional processing in the nucleus:
mRNA leaves the nucleus via the nuclear pores and enters the cytosol. With the help of initiation factors (proteins), the 5' end attaches to the small subunit of a ribosome. A tRNA possessing the 5'-CAU-3' anticodon sequesters the amino acid methionine (AUG) and settles in at the P site (peptidyl site). This is the signal for the large subunit to join and form the initiation complex. This process is termed initiation.
What are the 3 forms that RNA exists in?
mRNA, rRNA, tRNA
What are the cells directly involved in innate immunity?
macrophages, neutrophils, eosinophils, basophils, Natural killer cells
What are microfilaments made out of and what do they do specifically?
made of actin responsible for cytokinesis. Supports cell shape by bearing tension.
What are microtubules and what are they responsible for specifically?
made of tubulin responsible for mitotic spindle, cilila/flagella, intracellular transport of organelles and vesicles. Supports cell shape by bearing compression.
actin
major component of microfilaments
Na+, K+
major ions in establishing the resting potential
What is the role of albumin?
major osmoregulatory proteins in the blood
androgen
male sex hormone
Where does the Krebs cycle occur and what are the end products after each cycle?
matrix of the mitochondria. Products: 1ATP, 3NADH, 1 FADH2
secretory vesicles
may contain enzymes, growth factors, or extracellular matrix components; release their contents through exocytosis
Fill in the blank: In the mechanisms of chromosome movement chromatids move apart during _______ by the spindle fibers. _________ cause the chromosome movement
mechanisms of chromosome movement: chromatids move apart during anaphase by the spindle fibers. Microtubules cause the chromosome movement
lower brain
medulla, pons, mesencephalon, hypothalamus, thalamus, cerebellum, basal ganglia
MITOSIS OR MEIOSIS: 4 sperm cells or 1 egg (with polar bodies)
meiosis
MITOSIS OR MEIOSIS: Two divisions involved
meiosis
MITOSIS OR MEIOSIS: haploid (n) daughter cells
meiosis
MITOSIS OR MEIOSIS: tetrad formation (pairing of homologous chromosomes) and cross over
meiosis
What is the significance of meiosis?
meiosis introduces genetic variability by genetic recombination.
What is the first amino acid added to peptide chains?
methionine
What is the site of ATP production?
mitochondria
phospholipid bilayers
mitochondria are surrounded by two ___
endosymbiont theory
mitochondria may have evolved from a symbiotic relationship between ancient prokaryotes and eukaryotes
What are three facts about mitochondria that serve to support the endosymbiosis theory?
mitochondria replicate independently from the cell containing the mitochondria. mitochondria does not share the same genome with its host. mitochondria has their own ribosomes, which are different from the host's ribosomes in both sequence and structure.
Describe the process of aerobic decarboxylation.
mitochondrial matrix = convert pyruvate (3 carbons) to an acetyl group (2 carbons). 1 NADH made for every pyruvate. Only occurs in the presence of oxygen. Acetyl group attaches to Coenzyme A to make acetyl CoA.
MITOSIS OR MEIOSIS: No tetrad
mitosis
What is the function of the Golgi apparatus
modification and sorting of proteins
Golgi apparatus
modifies and packages proteins for use in other parts of the cell and outside the cell
What is the basic function of the Golgi Apparatus?
modifies and/or secretes macromolecules for the cell. RER make protein → modified in the Golgi → buds off golgi and secreted out of cell by exocytosis.
local mediators
molecules used for communication by the paracrine system
What role do monocytes play in this innate immunity?
monocytes circulate in the blood until they are needed. - They enter the damaged or infected tissue via diapedesis - once inside the tissues, monocytes mature to become macrohpages
All cellular organelles, such as mitochondria, is inherited from the _____.
mother
ventral horns
motor neurons in the somatic nervous system are located in the ___ of the spinal cord
acetylcholine
motor neurons of the somatic nervous system synapse directly on their effectors and use ___ as their neurotransmitter
(KNOW) *The basic anatomy of the digestive tract
mouth; esophagus; stomach; small intestine; large intestine; rectum and; anus.
active transport
movement of a compound against its electrochemical gradient; requires expenditure of energy
carrier population
multiple carrier populations make it more difficult to fight viral infections
Nearly all cells are capable of producing and storing some glycogen; however, only....
muscle cells and especially liver cells store large amounts
The functional unit of the kidney is the ____. Blood flows into the first capillary bed of this unit called ___.
nephron; glomerulus.
diffusion
net movement of compound X towards Y; for molecules without an electric charge, diffusion occurs in the direction of lower concentration
epinephrine, norepinephrine (adrenaline, noradrenaline)
neurotransmitters used by postganglionic neurons in the sympathetic system
How is skeletal muscle shaped?
non branched
NIDDM
non-insulin dependant diabetes mellitus
intracellular second messenger
often activated by the binding of a hormone activates or deactivates enzymes or ion channels
refractory period
once an action potential has begun, period of time in which no stimulus will create another action potential
Islet cell antibodies
one method to diagnose type I diabetes is to detect presence of
vertebrates
only ___ have myelinated axons
Where does nutrient and gas exchange occur for any tissue other than vascular tissue?
only across capillary walls, and not across arterioles or venules
fallopian tubes, respiratory track
only locations of cilia in the human body
How many strands in a molecule of double stranded DNA are transcribed?
only one! The template or antisense strand
Autotrophs
organisms that are capable of using CO₂ as their sole source of carbon
All fungi are heterotrophs. They are either ____ or ____
parasites or saprobes
What is a haustoria?
parasitic hyphae
A stomach ulcer may increase the acidity of the stomach. The stomach cells most affected by a stomach ulcer are?
parietal cells
*The descending loop of Henle is ___ to water; and the ascending loop of Henle is ___.
permeable to water; impermeable to water and actively transports sodium into the kindey.
plasma membrane
phospholipid bilayer that surrounds the cytosol of all prokaryotes does not contain steroids such as cholesterol but contain steroid-like molecules called hopanoids
What type of coenzyme is heme?
prosthetic
Capsid
protein coat that contains DNA or RNA
albumin
protein in blood; maintains the proper amount of water in the blood.
Phosphorylation typically occurs in the presence of a _____
protein kinase
Apoproteins
proteins embedded in surface of lipoproteins
spike proteins
proteins encoded from the viral nucleic acids protrude from envelope that is borrowed from the host cell used to bind to new host cells - cause virus to be infectious
transport/carrier proteins
proteins that are desesigned to facilitate the diffusion fo specific molecules sacross the membrane
In the electron transport chain, what force propels protons through ATP synthase to manufacture ATP?
proton-motive force
where most reabsorption takes place in the kidney
proxima:! tubule
What is a random mutation?
random changes in DNA sequence. Can be due to radiation, chemicals, replication error ...etc.
What is scenario 3 of a double crossover?
results in genetic recombination. The chromatids exchange, then 2 totally different chromatids on the same chromosome exchange. This is called the 4-strand double crossover. Results in 4/4 recombinants.
Describe scenario one for double crossover.
results in no genetic recombination. The chromatids involved in this double crossover exchange alleles at first, but then it exchanges them back, resulting in no net recombination. This is called the 2-strand double crossover. Results in 0/4 recombinants.
passive diffusion
returns the neuron to its resting potential after an action potential
What is the Lock and Key model?
rigid active site. Substrate fits inside the rigid active site like a key
spirilla
rigid helically shaped bacteria
bacilli
rod
What are some basic differences between rough ER and smooth ER
rough ER has ribosomes studded over it, smooth ERs don't. RER deals with protein synthesis, folding, modification, and export. SER deals with biosynthesis of lipids and steroids, and metabolism of carbohydrates and drugs
cocci
round
To denature DNA means to...
separate the two strands of the double helix, via breaking the hydrogen bonds with high salt, high pH or high heat solutions.
Golgi apparatus
series of flattened, membrane bound sacs that organize and concentrate proteins as they are shuttled by transport vesicles progressively outward
What do single crossovers result in??
single crossovers result in genetic recombination. The chromatids involved in this single crossover exchange alleles at a given locus. Results in 2/4 recombinants.
What are the Pyrimidines?
single ring structure: thymine and cytosine
DNA in prokaryotes
single, circular double stranged molecule of DNA which is twisted into supercoils and associated with histones in Archaea and proteins that are different from histones in Bacteria
What is the functional relationship between chromatids, centromeres, and kinetochores?
sister chromatids are duplicated copies of the chromosome. chromatids are joined at the centromere. There's a protein at the centromere called the kinetochore, where spindle fibers attach to pull the chromatids apart.
smooth ER
site of lipid synthesis, including steroids; helps detoxify some drugs
peripheral/extrinsic proteins
situated entirely on the surfaces of the membrane; ionically bonded to integral proteins or the polar group of a lipid
two aspects of a compound that affect its semipermeability
size and polarity; large the molecule = the less permeable the membrane is to that molecule; polar molecules with a molecular weight greater than sistance; greater the polarity of the molecule, the less permeable the membrane to that molecule
How many nuclei do smooth muscle cells contain?
smooth muscle cells contain one nucleus
Aldosterone acts on the distal tubule cells to increase ______.
sodium and potassium membrane transport proteins
Mutations in _____ cells are not passed to offspring, while mutations in ____ cells are passed to offspring.
somatic; germ
intermembrane space
space between the inner and outer membrane in mitochondria
enterocytes.
specialized absorptive cells in the villi of the small intestine
receptor
specific glycoprotein on host cell membrane (usually)
micelle
spherical structure of the plasma membrane with polar ends towards the solution and nonpolar ends toward each other
What happens during post translational modification?
sugars, lipids or phosphate groups may be added to amino acids.
Bolus is pushed into esophagus by _____, and then moved down via ____ action.
swallowing, peristaltic action.
spinal cord, brain and spinal cord
sympathetic signals originate in neurons whose cell bodies are found in the ___, and parasympathetic signals originate in neurons whose cell bodies are found in the ____
Unlike mitosis, homologous chromosomes pair with each other during meiotic prophase I in ______. Homologous chromosomes align themseles very precisely w/ each other, with the two copies of each gene on two different chromosomes brought closely together. The paired homologous chromosomes can be either called _____ or ______
synapsis bivalent tetrad
Describe wild type allele
the "normal" allele or phenotype for an organism. The wild-type is usually the most prevalent, although it doesn't necessarily have to be true.
What is recessiveness, and what is an example of this in human hair?
the "weak" allele. The recessive allele is only expressed if both copies are present. Only a single copy is needed for the dominant allele. The recessive allele is usually denoted as the lower case letter, the dominant allele is usually denoted as the upper case letter. For example, blond hair is recessive. Both alleles for blond hair need to be present, otherwise the hair is dark.
Upon secondary exposure to a pathogen, what type of cell elicits the immune response?
the Memory B-cell
3,out of, 2, into
the Na+/K+ pump moves __ sodium __ the neuron and __ potassium ___ the neuron
PNS
the ___ handles the sensory and motor functions of the nervous system
α-subunit
the ___ of a G-protein breaks free and may activate separate specific ion channels, a second messenger, intracellular enzymes, and/or gene transcription
resting potential
the ___ of a neuron is established by an equilibrium between passive diffusion of ions across the membrane and the Na+/K+ pump
The cell just went all apoptosis on us. Now what happens to it?
the apoptosed cell releases chemicals that attract macrophages, and gets engulfed
cytosol, ER lumen
the cell can be divided into two sides __ and ___
What happens in Metaphase of Mitosis?
the chromosomes align along the equator of the cell
CNS
the function of the __ is to integrate nervous signals between sensory and motor neurons
What happens, in general, during the electron transport chain?
the high energy molecules, NADH and FADH2, are broken down to produce energy.
negative
the inside of a neuron has a ___ potential difference compared to the outside
converging, less, away from
the lens of the eye is a __ lens; flattening the eye by relaxing the ciliary muscles makes the lens __ powerful, moving the focal point __ the lens
Eukaryotes lack the bacterial transcription regulation mechanisms such as the ____ (exists but very rare) and _____.
the operon and attenuation.
glycosuria
the presence of abnormally high levels of sugar in the urine
Explain what happens in the elongation step called translocation:
the ribosome shifts 3 NTs along the mRNA toward the 3' end. The tRNA that carried methionine moves to the E site where it can exit the ribosome. The tRNA carrying the nascent (newly formed) dipeptide moves to the P site, clearing the A site for the next tRNA. Translocation requires the expenditure of another GTP. The elongation process is repeated until a stop codon reaches the P site.
cytosol
the ribosomes in rough ER are attached to the __ side
cochlea
the snail-shaped tube in the inner ear where sound vibrations are converted into nerve impulses by the organ of Corti
effector cell
the target cell of the hormone
lever
the three bones of the middle ear act as a __ system; displacement is lessened, increasing the force
slowest
the transmission of the neural signal from one cell is the ___ part of the process of nervous system cellular communication
What is peristalsis?
the wave-like motion of smooth muscle that moves food through the digestive system
What is the composition and function of eukaryotic cilia and flagella?
they are made of microtubules cilia can be for locomotion, sensory, or for sweeping mucus. flagella is used for locomotion.
What is the secondary enzyme structure?
this is hydrogen bonding between the protein backbone. Examples include alpha helices and beta sheets (backbone H-bonding). For RNA, this is base pairing.
What is the primary enzyme structure?
this is the sequence of the protein or RNA chain.
malleus, incus, stapes
three bones in the middle ear
outer ear, middle ear, inner ear
three divisions of the ear
neurotransmitters, local mediators, hormones
three molecules that are used for communication in multicellular organisms
Codon:
three-nucleotide sequence on messenger RNA that codes for a single amino acid
How do osteocytes that are trapped between the lamellae of concentric rings in compact bone exchange nutrients?
through tunnels called canaliculi
tyrosine derivatives
thyroid hormones T3 and T4 catecholamines formed in the adrenal medulla: epinephrine and norepinephrine
tyrosine
thyroid hormones and the catecholamines
Virus
tiny infectious agents, much smaller than bacteria; comparable in size to large proteins Made up of capsid, tail, and tail fiber. Some have lipid-rich envelopes
What is the purpose for the delayed contraction of the AV Node?
to allow the atria and ventricles to fill with blood. They are slow to contract to allow for atrial emptying and ventricular filling. Basically, this delay allows the atria to finish their contraction, and to squeeze their contents into the ventricles before the ventricles begin to contract.
The primary cause of insulin resistance remains unclear.
true about Type 2 diabetes
The major enzymes released by the pancreas are? (6) They are released as ____.
trypsin, chymotrypsin, pancreatic amylase, lipase, ribonuclease, and deoxyribonuclease -Zymogens
Which amino acids strongly absorb in the UV?
tryptophan, tyrosine, and phenylalanine
Heterotrophs
use preformed, organic molecules as their source of carbon.
Describe anabolism
using energy to build stuff for storage
How can structural changes to a chromosome occur?
via deletions, duplications, translocations, inversions
How do fungi reproduce?
via spores or mycelial fragmentation.
virulent virus
virus following a lytic cycle
temperate virus
virus in a lysogenic cycle;
Bacteriophage
virus that infects bacteria Nucleic acid injected through tail after viral enzymes have digested a hole in the cell wall
Whenever you get a large intestine question on the MCAT, what should you think?
water absorption
The major functions of the large intestine are
water absorption and electrolyte absorption
The collecting duct is impermeable to ____, but it is also sensitive to ____.
water, ADH
What does it mean that DNA replication is semi-conservative?
when a new double strand is created, it contains one strand from the original DNA and one newly synthesized strand.
less, hyperpolarization
when a photon isomerizes the retinal in rhodopsin in rods, the membrane becomes __ permeable to sodium ions leading to ___
What do osteoclasts develop from?
white blood cells called monocytes
What does the sarcolemma do?
wraps several myofibrils together to form a muscle cell or muscle fibre.
Is cardiac muscle striated?
yes
Is skeletal muscle striated?
yes
all of the major enzymes in the pancreas are released as
zymogens
