Biology D
what is derived form cholesterol
steroid hormones: estrogen, progesterone, cortisone, cortisol, testosterone, and aldosterone Epinephrine and thyroxin are amino acid derived
sperm cell and egg cell unite to make a zygote this is called fertilization or
syngamy
bacteria derive their energy from
they do not have mitochondria and do not carry out the TCA cycle, however, they do carry out glycolysis and have their own electron transport system
about kinase
transfer phosphoryl groups
somatic cell is undergoing mitosis. At anaphase the chromosome number is
4N
Kingdom monera can be distinguished from other kingdoms by
70S ribosome
organs are constructed from which 4 basic tissue types
nervous, epithelial, muscle, and connective tissue
Sucrose is hydrolyzed into
sucrose : glucose + fructose Maltose : 2 moles of glucose Lactose : 1 mole galactose + 1 mole glucose
Nucleoside
sugar and base
about kangaroo rat
survives by eating dry seeds high in fat and carbohydrates but low in protein. oxidation of this fat provides the needed water for survival
Centrifugation works by spinning a tube of components at high velocities to create a force. The heavier a component is, the faster it will pellet out of the solution.
1.Whole cells and nuclei 2.Mitochondria, choloroplasts (if present), lysosomes, peroxisomes, golgi 3.Microsomes (vesicles of disrupted endoplasmic reticulum and pieces of plasma membrane) 4.Ribosomes, viruses, larger macromolecules
How many DNA strands are expected after 8 cycles of the polymerase chain reaction
2^8 x 2 Multiply by 2 because each DNA has 2 strands
bone
-Arm bones include the humerus, ulna, and radius -leg bones include the fibula, tibia, and femur -Osteoblasts are bone forming -Osteoclasts are bone reabsorbing -more info in picture
cell cleavage
-During cell cleavage, the embryo does not grow significantly in mass as mitosis occurs. Cleavage partitions the cell (zygote) into smaller cells. Gene transcription is shut down during cleavage as we see an increase in cell number. Thus, the ratio of nuclear to cytoplasmic material increases
what is unique to mammals
-Fish and frogs are not mammals but do have a backbone -Birds are not mammals but are warm blooded -Mammals contain hair, produce milk to nurse their young and have a lower jaw that is a single bone -3 bones contained in the middle ear are unique to mammals -The diaphragm muscle is unique to mammals and is the major muscle of inspiration -The diaphragm separates the thoracic cavity from the abdominal cavity
facts
-If an organism is too warm, blood vessels will dilate -If an organism is too cold, the blood vessel will constrict -The oncotic pressure tends to pull fluid into capillary -The hydrostatic pressure tends to push fluid out of a capillary
about ferns
-In ferns the predominant plant form is the sporophyte -Sporangia are structures in which spores are produced; clusters of sporangia are known as sori and are found on the lower surface of the leaf -vascular plants -large leaves with many veins
Facts
-Lymph nodes may contain lymphocytes and macrophages -Plasma cells produce antibodies -The greatest resistance to blood flow is in the arterioles -In the normal adult, there are 8 premolars, 8 incisors, 4 canines and 12 molars
sperm
-a sperm cell comes in contact with the jelly coat surrounding an egg known as the zona pellucida -The acrosome covers most of the head of a sperm cell -Sperm has very little cytoplasm compared to an egg cell -mitochondria are located in the midpiece of the sperm and supply energy for the tails' whip like movement -a sperm cell comes in contact with the zona pellucida -the membrane of the acrosome ruptures and releases its contents that exclude enzymes that act on the jelly coat and egg cell membrane
What requires a carrier protein
-active transport -Na+/K+ pump -facilitated diffusion -intracellular Ca+ pump -endocytosis is the result of a cell's plasma membrane and does not require a career molecule
what organs are involved in excretion
-skin excretes water and dissolved salts -liver processes nitrogenous waste for excretion -kidney coordinates the balance of excretion -lungs: CO2 and O2 diffuse at the blood-air barrier and are exchanged with the environment
enzymes
A competitive inhibitor will compete for the native site of the enzyme. The Vmax of the reaction is unchanged in competitive inhibition but decreases in non-competitive inhibition. Many enzymes contain metal ions usually held by coordinate covalent bonds from amino acid side chains or bound by nonprotein molecules called prosthetic groups. ex: an enzyme called Carboxy peptidase A contains Zn2+ in its active site which is needed for it to function properly
facts
A lymphatic vessel is most similar to a vein; they have internal valves The thymus makes thymosin which stimulates T-cell development. Once puberty is reached, the thymus gland shrinks and is replaced by fat. Lysozyme is an enzyme found in tears and saliva. This enzyme helps break down some bacterial cell walls. The coating of a microbe with antibodies to make t more "delicious" for phagocytosis is called opsonization. The functional capacity of T-cells is most influenced by the effects of aging. After age 60, declines in the immune system is most evident
Allelopathy
Allelopathy is type of interference competition, where the establishment of other individuals who would compete for a mutual resource is prevented, in this case using a toxic chemical. Intraspecific competition (E) occurs when competition occurs within the same species; in this case the plant is competing with all the other species of plants in the area.
A ? is created by the fusion of normal haploid gametes from different but closely related species
Allodiploid
facts
Alpha helix and beta pleated sheet are secondary structures held together by hydrogen bonds -quaternary structure is a property of proteins that consist of more than one polypeptide chain ex: hemoglobin has 2 alpha chains and 2 beta chains thus has a quarternary structure -myoglobin has a single chain thus no quarternary structure
The most diverse and abundant vertebrate are
Bony fish
brackish water
Brackish water means a mix between salt and fresh water, which would be found in an estuary. An estuary is a specific area where freshwater meets seawater. A mangrove swamp often grows near an estuary and is characterized by a mix of salt and freshwater.
most abundant waste product
CO2
about Ferns
Ferns are unique because they contain two separate living structures called the sporophyte and gametophyte. They are unique because they are not dependent on one another
about cell types
Fibroblasts are least specialized in connective tissue family. Involved in collagen and extracellular matrix synthesis. Cells are derived from primitive mesenchyme. Fibroblasts show the ability to differentiate into other cell types like adipose, muscle, bone, and cartilage cells.
Photosynthesis
CO2 is the carbon source in the sugar produced -The light dependent reactions occur in the thylakoid membrane Source of O2 produced is the H2O that is split during the light reaction -product of dark reactions is glucose
a stable complex of carbon monoxide and hemoglobin in red blood cells is termed:
Carboxyhemoglobin
matching
Chlorophyll: Mg+ Homologous structures: common ancestors Hypothalamus: Temperature regulation Meninges: covering around brain and spinal cord Carbon fixation: CO2 being converted into organic materials occur in the dark
If a solution turns black-blue due to Iodine what is it
Amylose which is found in starch
cartilage
Connective tissue regenerates most rapidly while ganglion cells of the CNS have virtually no ability to regenerate. Bone, liver, and surface epithelium has marked capacity for regeneration HEart and neurons of the CNS have no regeneration power. Cartilage is a connective tissue that is derived from mesenchyme. Mesenchyme is the embryonic connective tissue that gives rise t most of the connective tissue cells. Cartilage can be found in areas such as the trachea, tip of the nose, larynx, external auditory canal and external ear
Enzyme that unwinds DNA
Helices, use energy from ATP
Which vessel carries blood away from the liver and towards the heart
Hepatic Vein. It will empty into the inferior vena cava and allow blood to return to general circulation
Which antibody class can cross the human placenta
IgG
Which valve is at the junction of the small and large intestine
Ileocecal valve. It prevents the contents of the large intestine from entering the small intestine. Mitral and semilunar valves are in the heart
What is Apoptosis
Programmed cell death
some facts
Lysosomes have an acidic pH, this is where the enzymes of cellular digestion are found. Golgi apparatus contains a membrane, they are membrane bound- bound sacs involved in the packaging of glycoproteins. Oocyte development is halted at the primary Oocyte stage until puberty (meiosis is arrested in prophase I). During transduction, we see DNA transfer by a virus
Reptiles
Reptiles have thick skin, thick shelled eggs, an amnion and internal fertilization. however, they do not lose fills at any stage of development
about keystone species
allow for species maintenance. The density of strong competitors is reduced, such that competitive exclusion of other species does not occur.
What part of the flower catches pollen
The sticky part: stigma
Fixed action Patterns
Specific environmental stimulus triggers a complex, corrdinated behavioral response. Not learned
what happens to lactic acid produced in muscles
blood transfers lactate to the liver. The cori cycle allows the conversion of lactate back into glucose which can be carried back to the muscles via blood. The glyoxylate cycle occurs in plants and bacteria
what factor is responsible for the striation in skeletal muscle
Thin filaments are actin, they are the light I bands Thick dark bands are myosin filaments Actin is the most abundant cytoplasmic protein Alternating between these actin and myosin filaments gives skeletal muscle it's striated appearance
RNA polymerase
does not have proof reading ability, DNA polymerase does
when enzyme reaches Vamx
enzymes active site is fully saturated with substrate
cilia would be most affected by a drug that causes the destruction of
flagella and cilia are made of microtubules
Cytochromes
group of heme containing proteins found in the electron transport chain
What is in Kingdom Monera
includes blue green algae and the bacteria Paramecium is in kingdom protista Mushrooms are in kingdom fungi Green algae are in kingdom Protista
Pulse chase experiment
involves using a radioactive label on a protein to detect what is happening to a molecule in cells. In this technique, one can track the fate of proteins through a cell and learn important information about biochemical pathways
sequence of air
nasal cavity -> trachea -> bronchus -> bronchiole -> alveoli In alveoli, air sacs O2 and CO2 diffuse into and out of the blood stream through the capillary walls
after ovulation the ovarian follicle creates
ovarian follicle becomes the corpus luteum Corpus luteum will provide progesterone and estrogen that will help blood vessel growth
earth
oxygen makes most of the earths crust earths most abundant gas in the atmosphere is nitrogen
High energy compounds
phosphoenolpyruvate acetyl CoA ATP
what enzymes catalyzes glucose to fructose
phosphoglucose isomerase
bones and muscles
pictures
ear order from outside to inside
pinna, auditory canal, tympanic membrane, malleus, incus, stapes, semicircular canal, cochlea, and eustachian tube
suitable vector for recombinant DNA cloning
plasmids and bacteriophages (a virus)
birds are likely the decedents of
reptiles both lay eggs, have scaly legs, horny beaks and may contain many reptilian internal structures
failure to separate homologous chromosomes at anaphase I
result will be 4 cells: n-1, n-1, n+1, and n+1 If failure was at anaphase II then it would be n+1, n-1, n, n
reverse transcriptase its found in what
retroviruses RNA viruses that use the enzyme reverse transcriptase to copy their RNA genome into DNA
about viruses
reverse transcriptase is an enzyme seen in retroviruses in which RNA, not DNA is the genetic material. DNA is made from RNA and is incorporated into the host cells Viruses have -DNA or RNA but not both -are obligate intracellular parasites -unable to reproduce outside a living cell -capsid of the virus may be spherical or rod like
matching
rhizoids: root like absorptive structures in some fungi and plants seed: similar to a fertilized egg sepal: encloses and protects the flower bud in angiosperms seed: includes the young, dormant sporophyte, nutritive tissue, and outer protective coat moss and ferns have no seeds
organisms that cause diseases in man
roundworms and flatworms
Which hormone is highest during the secretory phase of the menstrual cycle
secretory phase is the final stage Corpus luteum produces progesterone which allows the endometrium to be receptive to implantation of the blastocyst
there are ? pairs of cranial nerves that are ?
12 pairs of cranial nerves that arise from various locations on the underside of the brain -cranial nerves can be mixed, sensory, or motor. However, most are mixed
Dino the dinosaur most likely lived
230 million years ago during the Triassic Period and became extinct 65 million years ago
amount of blood in an average sized adult
5 quarts Blood is a tissue that carries raw materials, wastes, and substances to and away from cells. Plasma is the liquid portion of the blood and contains hundreds of plasma proteins such as albumin, fibrinogen, and globulin. Albumin is the most abundant and is important in maintaining the blood's osmotic pressure
promoter site
6 protein enzyme complex called RNA polymerase binds to a specific site on the DNA called the promoter site, hence determining where transcription begins Transcription and translation have several differences in prokaryotes and eukaryotes, but both employ a promoter site to determine where transcription begins
Dihybrid crosses
9/16: both traits dominant 3/16: one dominant other recessive 3/16: one dominant other recessive 1/16: both recessive
What type of reaction is involved in the assembly of a peptide bond? A. Condensation reaction
A condensation reaction involves the for - mation of a water molecule by combin - ing an H + ion with an OH - ion during the creation of a polymer. Two examples are the formation of polysaccharides and the formation of polypeptides. A hydrolysis reaction (choice B) is the exact opposite: a polymer is split ("-lysis") into monomers through the addition of a water ("hydro-") molecule across the bond. Catabolic re - actions (choice C) are those that break things down. Hydrolysis is a catabolic reaction. This is not the type of reaction used to form bonds. Fermentation (choice D) has to do with the production of ATP through anaerobic respiration (glycolysis in the absence of oxygen) and has nothing to do with polypeptide formation. Meta - bolic reactions include both catabolic and anabolic (building up) reactions. While 7 polypeptide formation is certainly an ex - ample of an anabolic reaction, choice A is more specific and thus better than E
Defects in the ectoderm during development could lead to damage of what organ? A. Stomach B. Lungs C. Brain D. Heart E. Kidneys
A defect in the ectoderm would directly cause damage to the organs it develops. The table below breaks down what you need to know for each germ layer. Germ layer Organ development Ectoderm Epidermis of skin, hair, nails, nervous system, lens of eye, enamel of teeth Mesoderm Dermis of skin, muscle, skeleton, circulatory system, gonads, kidneys, respiratory tracts, notochord Endoderm Lining of digestive and layer of respiratory tracts, liver, pancreas
Plant structures
A pollen grain is an immature gametophyte with hard covering. The anther is the chamber where pollen develops The pistil is the female part of the plant; it consists of the stigma, style, and ovary. The stigma is sticky and will catch the pollen The style is a tube like structures connecting the stigma to the ovary. The ovary encloses one or more ovules where the monoploid egg nucleus is found The stamen is the male part of the plant The petal is the colorful part of the plant that attracts insects, they have odors as well In the plants, the haploid gametophyte is multicellular while in animals is it unicellular
immunity
-A vaccination is an immunization against a given pathogen; it is artificially acquired. Production of immunological agents begins. This production is active immunity that is artificially acquired. If you recover from chicken pox immunity was conferred by active immunity that was naturally acquired Antibodies may be transferred from one individual to another providing passive immunity ex: mother transfers antibodies across the placenta (naturally acquired) or in the case of rabies; a person would b treated by injecting antibodies from a person who has already been vaccinated. This is passive immunity that is artificially acquired
Facts
-A zymogen such as pepsinogen is the inactive form of an enzyme. -Estrogen is a steroid and being a steroid has receptors within the cell -When a peptide hormone like insulin is present, it binds to a receptor and sets off a chain of events within the cell -Endocytosis may involve the transport of liquid droplets into animal cells, the process utilizes ATP and is sometimes called pinocytosis -During endocytosis, we may also see solid material taken into the cell -Material attaches to the cell membrane and induces the membrane to bulge inward producing a vacuole. When the substance is solid, the process is called phagocytosis
facts about NS
-Acetylcholine is the primary neurotransmitter of the parasympathetic nervous system -Norepinephrine is the primary neurotransmitter of the sympathetic NS -Acetylcholine has excitatory and inhibitory effects on muscles and glands throughout the body -Action potential is an all or nothing event
facts
-Angonistic behavior can result if two animals conflict over a mate of food source -Xylem will transport water and minerals from the soil throughout a plant -The Casparian strip is a waxy band in plants that aid in water control -Main solute transported by the phloem is sucrose
facts
-Chemotrophs are organism that use redox reactions to produce ATP -Ubiquinone, also called Coenzyme Q is a lipid soluble electron carrier seen in the electron transport chain -Eukaryotes and prokaryotes both use the electron transport chain -In oxidative phosphorylation, electrons are transferred from NADH to O2 through an electron transport chain to produce ATP -Bacteria use multiple electron transport chains, sometimes at the same time. Similar to eukaryotes, their electron transport chains involve proton pumps -In typical eukaryotic cell the pH is around 7.4 -Amino acids are amphoteric, they act as acids or bases pH of gastric juice is under 2 -Hemoglobin and myoglobin are water soluble globular proteins -Glycine is the only optically active amino acid since it has no chiral centers
facts
-Differentiation occurs when a cell has become specialized -Differentiation will arise as a result of selective gene expression -An annelid has a closed circulatory system -An arthropod has an open circulatory system -Annelids are the segmented worms, the nephridia is their excretory organ
The left atria and left ventricle are connected by
-Four main heart valves are mitral (bicuspid), tricuspid, and the 2 semilunar valves: the aortic and pulmonary valve -The right atria and ventricle are connected by the tricuspid valve -Left atria and ventricle are connected by the mitral valve -There are 2 heart sounds: lub and dub lub = closing of AV valves dub = closing of semilunar valves Coronary sinus is a wide venous channel that receives blood from the coronary veins and empties into the right atrium of the heart
Major Histocompatibility complex, MHC
-Important in distinguishing self from non self -This complex is a collection of molecules which are responsible for stimulating the rejection of tissue grafts and organ transplants -MHC triggers T-cells to attack and begin a cell mediated response against the donated organ
genetic facts
-In achondroplasia, we see dwarfism. It is an autosomal dominant disorder -In progeria, we see autosomal recessive inheritance where a premature aging is seen -Trisomy is associated with down syndrome -an inactive X-chromosome is called a barr body -the probability of a crossover occurring between two genes on homologous chromosomes is increased if they are further apart
info
-Platelets have no nucleus -Osteoblast will create new bone -Myoglobin consists of a single chain but does not store O2 in muscle. Hemoglobin, another globular protein consists of two alpha chains and two beta chains. Collagen is a fibrous protein and consists of a triple double helix; it is very rich in glycine. A meshwork of macromolecules is called the extracellular matrix. The extracellular matrix is rich in collagen. A large percentage of vertebrate weight consists of extracellular matrix as seen in bone. Mineralized ground substance and collagen fibers are a distinguishing feature of bone
Hyperthyroidism
-TSH is made in the pituitary gland in the brain -TSH stimulates the thyroid gland to make thyroxin -If thyroxin in the blood is high, then this gland releases less TSH. Thus, a low TSH level means you may have hyperthyroidism -Thyroid uses iodine in food to make T4(thyroxin) and T3(triiodothyronine) -Graves disease is an autoimmune disease that causes too much thyroid hormone to be made and the result is hyperthyroidism , symptoms: anxiety, weakness, and increased heart rate
about plants
-The leaf has a spongy mesophyll layer which the O2 and CO2 diffuse across and a palisade mesophyll layer that has chloroplasts and is exposed to light -plants have cellulose containing CELL WALLS not cell membranes -xylem transports water up the roots of plants -calvin cycle can occur during day or night -plants hormones: auxins, gibberellins, kinins, and ethylene
about Krebs (TCA) cycle
-a phase of aerobic respiration - 3 NADH, 1 FADH2, and 1 GTP are produced per turn of the cycle - the reaction occurs within the matrix of the mitochondria - one molecule of glucose produces 2 turns of the cycle -pyruvate loses CO2 in the matrix of the mitochondria and combines with CoA to becomes acetyl CoA. it is acetyl CoA that enters the TCA cycle by condensing with oxaloacetate to form citrate
about liver
-albumin storage - bile production -destruction of worn out red blood cells -converts nitrogenous waste into urea -glycogen stored in liver, not glucose. the hormone insulin, secreted by the pancreatic beta cells decrease blood glucose levels and allow it to be converted to glycogen where it is stored in the liver and skeletal muscle
fetal circulation
-blood is oxygenated at placenta -blood is shunted away from the lungs by ductus arteriosis -fetal lungs receive very little blood -fetal hemoglobin has a higher affinity for O2 than adult hemoglobin -Foramen ovale is responsible for contributing to the shunting of blood away from the lungs by connecting the right and left atrium NOT ventricles
facts
-blood travels slowest in capillaries and has lowest average blood pressure in veins -CO2 reacts with water in equilibrium CO2 + H2O -> H2CO3 -> HCO3- + H+ -Oxygenated blood from the pulmonary veins goes into the left atria of the heart -In the heart of an amphibian like a frog, 2 atria and one ventricle are observed -lub and dub sounds are due to the closing of heart valves.Lub is the closing of the AV valve, dub is the closing of the semilunar valve
about bones
-bone contains blood and nerves -Triglycerides are contained in the yellow bone marrow -Ground substances and collagens are a distinguishing feature of bone -Haversian canals are interconnected channels for blood vessels and nerves _Once trapped within the small spaces of bone, osteoblasts mature into osteocytes. Fibroblasts produce extracellular fibers and ground substances of connective tissue Collagen is made by the fibroblasts as well Red blood cells: O2 transport WBC: infections Macrophage and neutrophil: phagocytosis Plasma cells: antibody production Mast cells: histamine release
molecule that participates in endocytosis by forming a polyhedral lattice around coated pits
-clathrin -plasma membrane invaginates and fuses to form an endocytic vesicle. this process allows things such as cholesterol to enter a cell
some fact
-cleavage begins while the zygote is still present in the fallopian tube -fertilization>morula>blastula>gastrula> -during ovulation, the follicle ruptures and releases secondary oocyte -in hard shelled eggs, the allantois stores waste from protein metabolism -in humans, the allantois is involved in oxygen and nutrient transport and becomes part of the placenta -eventually, allantois becomes the umbilical cord
animal behaviors
-courtship precedes mating in animals -appeasement behavior allows dominant hierarchies to be maintained and will inhibit other animals from attacking -agonistic behavior may or may not result in physical combat
About Fungi
-eukaryotic heterotrophs -secrete digestive enzymes and then absorb the soluble products of digestion -composed of filaments called hyphae; collectively hyphae are called mycelium -can reproduce sexually or asexually -haploid state predominates but they do alternate between haploid and diploid stages -saprophytic, they break down the remains of living organisms that have died -immotile and have cell walls -a fungus not only attacks dead matter but may attack living tissue like in Athletes foot -more similar to human cells than bacterial cells
about smooth muscle
-found in aorta, pulmonary artery, esophagus and bladder -it is mononucleated -involuntary muscle that is slow to contract -they respond to stimulation with action potential
nervous system facts
-functional unit of the nervous system is the neuron or nerve cell -dendrites are nerve fibers that transmit impulses toward a neuron cell body - Multiple sclerosis involves myelin sheath destruction -action potentials usually travel along an axon away from the cell body
facts
-glycogen is a branched polymer of glucose -glycogen reprsnts a stored energy called "potentail energy" and is found in skeletal muscle and the liver -starch and glycogen are polymers of alpha glucose -glycogen can be stored intracellularly -a greater number of polysaccharides can be made from 20 amino acids than polypeptides -polysaccharides can be branched or linear whereas polypeptides are only linear -polysaccharides can be alpha or beta
Dicotyledons
-have veined leaves and vascular bundles arranged in a ring -Dicotyledons have seeds with 2 cotyledons ex: mapple and apple trees
about ATP
-hydrolysis of ATP is exergonic ATP hydrolysis releases energy that can be utilized to drive endergonic reactions At pH=7 ATP is negatively charged ATP is the universal carrier of free energy in biological system
angiosperms
-in monocots, the stem vascular bundles are vascularized in monocots the leaves have parallel veins -conifers are the oldest and largest trees of the world -gymnosperms were the first plants to have seeds -evolutionary path: bryophytes > gymnosperms > angiosperms
Epinephrine
-increase heart rate, respiratory rate -increase blood glucose, blood flow to skeletal muscles -increase rate of glycogenolysis -will constrict blood vessels to decrease blood supply to digestive tract and kidneys -dilation of pupils -increase blood flow to brain and blood pressure
some genetic facts
-microtubules comprise the spindle fibers -prophase is the longest mitotic stage; anaphase is the shortest -total DNA content in cells is the genome -DNA is highly conserved and is passed from generation to generation
about eye
-most eye volume is made up of a jelly like substance called virteous humor -the watery aqueous humor fills the anterior eye chamber -light enters the eye at the cornea while the virteous and aqueous humor help focus light onto the retina -sclera : white portion of the eye -retina: inner layer of eye containing photoreceptors -iris : colored portion of the eye
about kidney
-not enough ADH (vasopressin) = lose water, large quantities of urine would be produced. This is seen in diabetes insipidus. sugar in urine = diabetes mellitus Path of urine: loop of Henle -> distal convoluted tubule -> collecting duct The proximal convoluted tubule is where most reabsorption occurs; the glomerulus is involved with blood filtration. it is actually a capillary bed lying in the Bowman's capsule. fluid from the blood is filtered through the glomerulus in a process called glomerular filtration. the glomerular filtrate lacks blood cells and proteins. substances such as sugars are activerly reabsorbed. thr driving force for this filtration is the blood pressure (hydrostatic pressure within the glomerulus). The distal convulted tubule is the main area where secretion (K+ . H+ by active transport and NH3 by diffussion ); H+ secretion regulates blood pH
microscopes
-phase contrast microscopy can be used to view live cells; no staining is required -dark field microscopy views live cells or flagella that are too thin to be seen by phase contrast microscopy -electron scanning microscopy may be employed to view mitochondrial surfaces; cells are not alive -electron microscopes reveal many organelles but the chemical and physical methods employed kill the cell
some facts
-prolactin is produced by anterior pituitary -prolactin is a hormone that stimulates milk secretion in mammals -The sea urchin can develop a touch protective envelope called the fertilization membrane as a block to polyspermy -In parthenogenesis, an egg develops without fertilization as seen in wasps -when a sperm enters an egg the egg surface changes as a wave of negativity spreads out over the surface, thus preventing other sperm from entering
about skin
-skin is made of the outermost epidermis, followed by the dermis consisting mostly of connective tissue, hair follicles, sensory receptors, erector muscles, sweat and sebaceous glands. Below the dermis is fatty tissue that serves as a cushion and an insulator. The epidermis has no blood supply and depends on the dermis for oxygen and nutrients. Several layers of skin make up the epidermis: Strataums germinativum, spinosum, granulosm, lucidum, and corneum
about sweat
-some sweat glands are apocrine: glands that respond to stress. -Some are eccrine: responsible for maintenance of body temperature. -as we age the activity of sweat glands decrease and may become fibrous tissue. the skin also becomes dry and loses oil; this is due to a decrease in sebaceous gland activity. As body temperature increases, blood vessels dilate. this allows blood to enter the dermis and dissipate some of the heat
some facts
-spermatogenesis partitions cytoplasmic volume equally into 4 function spermatozoa -narrow opening or neck of the human uterus is known as the cervix -once released from the ovary, the egg is moved into the fallopian tube by the action of beating cilia located within the tube -a positive pregnancy test will show the presence of human chronic gonadotropin (hcG) in the urine
about development
-the placenta consists of maternal and embryonic tissue -during the menstrual cycle, a midcycle surge of LH causes ovulation -the amnion is a fluid filled sac that will protect the embryo from mechanical shock -three germ layers are completely formed during late gastrulation -the umbilical cord is not avascular but is well endowed with blood vessels. It does not, however, connect the embryo to the yolk sac, allantois, and amnion. A protective membrane develops called the chorion. The chorion becomes part of the placenta and secrets chorionic gonadotropin hormone which will maintain the corpus luteum. The corpus luteum will secrete progesterone that will help maintain the uterine lining. After about 3 months, the placenta produces the needed progesterone and estrogen
where is gas exchange in an insect
-tracheae: extensive system of tubes that permit air to directly reach cells within the body -single celled organisms respire via the cell membrane -aquatic animals respire via gills -in humans, the alveoli is the site of gas exchange of CO2 and O2 in the lungs -annelids have gas exchange in the mucus cells on the skin
some facts
-when amino acids are absorbed by liver cells, a series of chemical reactions take place. First, the amino group is removed; this is called deamination. The amino group is then reduced to NH3. NH3 is made into urea in the liver by the ornithine cycle. The urea can diffuse into the blood and be excreted in the urine (the rest of the amino acid is recycled or perhaps oxidized for energy needs. Amino acids can also produce glucose in a process called gluconogenesis
Organelles
. Golgi complex The golgi complex is responsible for the transport of various substances in vesicles, and modifies the products of the endoplasmic reticulum: proteins can be glycosylated, phosphorylated, or sulfonated in the golgi complex so the answer choice is correct. The golgi complex consists of flattened sacs called cisternae. B. Ribosome The ribosome is responsible for synthesis of proteins, but not their subsequent packaging or modification; therefore the answer choice is incorrect. Ribosomes can be found freely in the cytosol or on the rough endoplasmic reticulum, where they allow the synthesized protein to be transferred into the endoplasmic reticulum for further modification. C. Nucleus The nucleus of a cell is responsible for packaging and replication of DNA, as well as the transcription of RNA. It does not participate in the packaging of proteins, and does not import or modify products from the endoplasmic reticulum; therefore the answer choice is incorrect. D. Centriole A pair of centrioles make up a centrosome, found in the nucleus of animal cells which serve as microtubule organizing centers during cell division. These processes are unrelated to protein packaging and modification of the endoplasmic reticulum's products; therefore the answer choice is incorrect. E. Lysosome Lysosomes are vesicles produced from the golgi that contain digestive enzymes for breaking down nutrients, cell debris, and bacteria. These activities are unrelated to protein packaging and product modification; therefore the answer choice is incorrect. The interior of lysosomes have a lowpH; they are also known to function in apoptosis (by releasing their contents to destroy cells) and autophagy (intracellular breakdown of unneeded cell components). Note that while the endoplasmic reticulum and golgi complex can both be involved in protein modification, the question specifies the organelle that modifies the products from the endoplasmic reticulum, narrowing the correct answer down to the golgi complex.
Hormones
A. Aldosterone Aldosterone is a mineralocorticoid, which are a class of steroid hormones. Steroid hormones are synthesized from cholesterol in the smooth endoplasmic reticulum; therefore the answer choice is incorrect. Aldosterone (released from the adrenal cortex) acts on the distal convoluted tubule and collecting duct of the kidney to increase reabsorption of Na+ and excretion of K+. This leads to passive reabsorption of water in the nephron, which causes blood volume and blood pressure to rise. B. Cortisol Cortisol is a glucocorticoid, which are a class of steroid hormones. Steroid hormones are synthesized from cholesterol in the smooth endoplasmic reticulum; therefore the answer choice is incorrect. Cortisol is released from the adrenal cortex and primarily raises blood glucose levels. It is a stress hormone. C. Epinephrine Epinephrine is a catecholamine, a class of peptide hormones. While the catecholamines are water-soluble, they are not steroids or otherwise derived from cholesterol, so the answer choice is correct. Epinephrine is released from the adrenal medulla and is sometimes referred to as adrenaline. It functions in "fight or flight" response and raises blood glucose levels. It causes vasoconstriction to internal organs and the skin, but causes vasodilation to the skeletal muscles and increases the respiratory and heart rate. D. Testosterone Testosterone is a gonadal steroid hormone. Steroid hormones are synthesized from cholesterol in the smooth endoplasmic reticulum; therefore the answer choice is incorrect. Testosterone is primarily produced by the interstitial cells of the testicles. Testosterone functions in spermatogenesis and is responsible for male secondary sex characteristics. E. Progesterone Progesterone is a gonadal steroid hormone. Steroid hormones are synthesized from cholesterol in the smooth endoplasmic reticulum; therefore the answer choice is incorrect. Progesterone is produced by the ovaries (later in pregnancy, the placenta also produces progesterone) and functions in the menstrual cycle and the development and maintenance of the endometrial wall and fetus. Birth control pills frequently use high doses of progesterone (or progesterone and estrogen together) to cause negative feedback that suppresses LH and FSH levels, which in turn prevents ovulation from occurring.
Evolution
A. Allopatric speciation Allopatric speciation describes the formation of a new species as a result of a population being divided by a geographic barrier. Interbreeding between the two split populations is prevented and gene frequencies can then potentially diverge due to natural selection, mutation, and genetic drift. If the gene pools sufficiently diverge, a new species can form. The question describes a lion population separated by a river, which is a geographic barrier, so the answer choice is correct. B. Sympatric speciation Sympatric speciation describes the formation of new species without the presence of a geographic barrier - in the question the population of lions is separated by a river (a geographic barrier); therefore the answer choice is incorrect. Sympatric speciation can occur a number of ways: balanced polymorphism (natural selection due to multiple alleles being maintained in the population, allowing those with certain alleles greater ability to survive and reproduce where other members of the same species in the same geographic area without the same alleles cannot), polyploidy (often seen in plants), and hybridization. C. Adaptive radiation Adaptive radiation describes the rapid evolution of multiple species from a single ancestor. This occurs when the original species is introduced into an area with a broad range of environmental conditions available for colonization. Since there is no geographic barrier involved with adaptive radiation, the answer choice is incorrect. The multiple species of finches that Charles Darwin discovered on the Galapagos Islands were the result of adaptive radiation. D. Disruptive selection Disruptive selection occurs when an environment favors extreme or unusual traits on the very ends of a spectrum, while selecting against the more common traits. This is unrelated to speciation resulting from a geographic barrier; therefore the answer choice is incorrect. An example of disruptive selection would be a moth population that has a spectrum of color from white to black (with varying shades of grey in between) living in an area with white and black rocks. If a predator arrived, the grey moths would stand out on the white and black rocks, and would be eaten. The white and black moths would be able to hide on the matching colored rocks and would not be eaten. As a result, disruptive selection would occur and those moths at the ends of the spectrum (white and black) would survive with greater frequency. The image below shows the results of disruptive selection, which the red curve indicating the frequency of population along a spectrum of a given characteristic before, and the blue curve showing the results after disruptive selection. E. Natural speciation Natural speciation refers to a speciation event as a result of evolution occurring naturally over time, in contrast to artificial speciation which is a result of intentional methods such as selective breeding that result in the creation of a new species (for example, many domesticated dog breeds are considered to be the result of artificial selection over long periods of time). Natural speciation includes processes such as allopatric speciation and sympatric speciation, but it is not specific enough to geographic barriers to be the best answer choice (unlike answer choice A, allopatric speciation); therefore the answer choice is incorrect.
Biomes
A. Deciduous forest The deciduous forest biome is characterized by cold (but not particularly harsh) winters, warm summers, and moderate levels of precipitation. It has deciduous trees that shed their leaves during the winter, not coniferous trees; therefore the answer choice is incorrect. Due to the shedding of leaves, the soil in deciduous forests is rich. This biome is characterized by vertical stratification (plants and animals live on the ground, in low branches, and high in treetops). B. Savanna The savanna biome is characterized by warm temperature year-round, with some small seasonal variation. There is very little precipitation in terms of rainfall, and the dry season can last many months each year. These conditions do not match the question (describing long harsh, snowy winters); therefore the answer choice is incorrect. Fires are common during the dry season. Plants in this biome consist of grasses and scattered trees with small leaves. Animals in this biome consist primarily of large plant-eating mammals (e.g. zebras) and their predators (e.g. hyenas). C. Tundra The tundra biome is characterized by cold winters (to the point that the top layer of soil freezes). In the summer, the top layer thaws, but deeper soil (permafrost) remains frozen year-round. The summers are still relatively cold (generally average less than 50° F), and there is very little precipitation or vegetation; therefore the answer choice is incorrect. Plants in this biome consist of shrubs, grasses, mosses, and lichens (permafrost restricts the growth of plant roots). Animals in this biome include musk oxen, caribou, arctic hares, and arctic foxes. D. Taiga The taiga biome (sometimes referred to as boreal forests), located south of the tundra biome, is the largest terrestrial biome. It is characterized by very long, harsh winters and precipitation in the form of heavy snow, along with short rainy and humid summers. The primary form of vegetation is coniferous forests. These characteristics all match those described in the question, so the answer choice is correct. E. Chaparral The chaparral biome is characterized by highly seasonal precipitation, with rainy winters and dry summers. The scattered vegetation in this biome consists primarily of shrubs, grasses, and herbs. Animals include deer and goats. The chaparral biome is found along the California coastline, and many California fires happen here. These conditions do not match those stated in the question;
Genetics Terms
A. Dominant Sickle-cell disease is an autosomal recessive condition, not dominant; therefore the answer choice is incorrect. Even without knowing the method of inheritance of sickle-cell disease, one should recognize that the question does not describe a mode of inheritance but instead several phenotypic outcomes, which is not specific to autosomal dominant disorders. B. Polygenic inheritance Polygenic inheritance describes the interaction of multiple genes to shape a single phenotype, but the question describes the opposite - one defective gene causing multiple phenotypic changes; therefore the answer choice is incorrect. Examples of polygenic inheritance include phenotypes with continuous variations, including height and skin color. C. Pleiotropy Pleiotropy describes when a single gene has more than one phenotypic expression, so the answer choice is correct. For example, if a mouse had a single gene that determined both the color of its fur and the shape of its ears, the gene would be said to exhibit pleiotropy - a single gene has determined multiple separate phenotypes. In this case, a defective hemoglobin gene results in multiple phenotypic changes, indicating pleiotropy. D. Epistasis Epistasis describes when one gene affects the phenotypic expression of a second gene. This may initially seem an appealing answering choice, but epistasis does not result in several phenotypic outcomes - rather, it is the control of a single phenotypic outcome of a separate gene; therefore the answer choice is incorrect. An example of epistasis: say a mouse has a "fur color gene", which determines whether the mouse's fur is brown or black. If a second gene controlled the production of pigment, and this gene was mutated such that no pigment was produced, the mouse would be white. Here, one gene (pigment production) affected the phenotypic expression of a second gene (fur color). E. Linked genes Linked genes are genes which physically reside close together on the same chromosome and do not assort independently. The question asks about a single defective gene causing multiple phenotypic changes, not the relative locations of multiple genes, so linked genes is irrelevant as an answer choice; therefore the answer choice is incorrect. Genes which are linked are expected to have recombination frequency less than 50%, whereas genes that are unlinked are expected to have a recombination frequency greater than 50%.
Which of the following lack a true coelom? A. Flatworms B. Annelids C. Echinoderms D. Chordates E. Mollusks
A. Flatworms Flatworms - from the phylum Platyhelminthes - are acoelomate, which means they lack a true coelom, so the answer choice is correct. The coelom is a cavity derived from the mesoderm in certain animals. Platyhelminthes is the only phylum of triploblasts that lacks a coelom. Other examples of Platyhelminthes include trematodes, flukes, tapeworms, and planarians. B. Annelids Annelids are coelomate, which means they possess a coelom; therefore the answer choice is incorrect. The coelom is a cavity derived from the mesoderm in certain animals. The Annelid phylum includes earthworms and leeches. C. Echinoderms Echinoderms are coelomate, which means they possess a coelom; therefore the answer choice is incorrect. The coelom is a cavity derived from the mesoderm in certain animals. Examples of the Phylum Echinodermata include starfish, sea cucumbers, and sea urchins. Echinoderms (along with Chordates) are the only phyla with endoskeletons. D. Chordates Chordates are coelomate, which means they possess a coelom; therefore the answer choice is incorrect. The coelom is a cavity derived from the mesoderm in certain animals. Examples of the Phylum Chordata include tunicates, lancelets, and all vertebrates. E. Mollusks Mollusks - from the phylum Mollusca - are coelomate, which means they possess a coelom; therefore the answer choice is incorrect. The coelom is a cavity derived from the mesoderm in certain animals. The Mollusca phylum includes the bivalves (clams, oysters), gastropods (snails, slugs) and cephalopods (octopus and squid). Coelomate Summary - The parazoa animals of the animal kingdom lack true tissues (those of the phylum Porifera), and the phylum Cnidaria are diploblast, having only two tissue types. Of the triploblast animals, there are three types: acoelomate (lack a true coelom), pseudocoelomate (have an internal cavity, but one that is not completely lined by mesoderm derived tissue), and coelomate (have a cavity lined by mesoderm derived tissue). Acoelomates: Platyhelminthes Pseudocoelomates: Nematodes, Rotifers Coelomates: Annelids, Mollusks, Arthropods, Echinoderms, Chordates
Biomolecules
A. Glycogen The molecular makeup of glycogen does not contain any nitrogen; therefore the answer choice is incorrect. Furthermore, glycogen is not found in the nucleus. Glycogen is a carbohydrate polymer of alpha glucose molecules that stores energy in animal cells. B. Actin Actin is found in both the cytoplasm and the nucleus, so this may initially appear to be a tempting answer choice. As a protein (comprised of multiple amino acids), it also contains nitrogen. However, the question points out that no sulfur is found in the extracted biomolecule. Knowing that actin is a protein microfilament, one should be aware that cysteine and methionine - amino acids found in many proteins, including actin - contain sulfur; therefore the answer choice is incorrect. Actin is found in microfilaments, which play important roles in skeletal muscle contraction, the cleavage furrow formed during cytokinesis, and the structure of pseudopods. C. DNA DNA is abundant in nitrogen (due to the nitrogenous bases that are part of nucleotide structure). Additionally, DNA contains no sulfur and is found in the nucleus - but only the nucleus. It is not present in the cytoplasm; therefore the answer choice is incorrect. Note that the cellular processes involving DNA - replication and transcription - take place solely within the nucleus. D. RNA Do not let the application style of the question overwhelm you; answering this question is a straightforward matter of identifying which of the biomolecules presented in the answer choices match the criteria of the question. RNA is abundant in nitrogen (due to the nitrogenous bases that are part of nucleotide structure). Additionally RNA contains no sulfur and is found in both the nucleus (as a result of transcription) and the cytoplasm (where mRNA, tRNA, and rRNA are all found in the process of translation). As RNA is the only biomolecule that fits all the criteria specified in the question, it is the most likely biomolecule extracted by the researcher, there the answer choice is correct. E. Cholesterol The molecular makeup of cholesterol does not contain any nitrogen; therefore the answer choice is incorrect. Furthermore, cholesterol is not found in the nucleus. Cholesterol, a type of steroid, is an amphipathic lipid 4-ringed structure. It is a critical component of animal cell membranes and plays an important role in maintaining membrane fluidity and rigidity.
Nematoda Annelida Mollusca Echinodermata Platyhelminthes
A. Nematoda Nematoda have a complete digestive system; therefore the answer choice is incorrect. They are triploblasts with bilateral symmetry, and (like Rotifera) are pseudocoelomates. Examples of Nematoda include round worms, hook worms, and the model organism C. elegans. Many Nematoda are parasitic and contain a thick protective outer layer known as the cuticle. B. Annelida Annelida have a complete digestive system; therefore the answer choice is incorrect. They are triploblasts with bilateral symmetry, and are coelomates with segmented bodies and closed circulatory systems. Examples of Annelida include earthworms and leeches. C. Mollusca Mollusca have a complete digestive system; therefore the answer choice is incorrect. They are triploblasts with bilateral symmetry, and are coelomates with open circulatory systems (with exception to cephalopods, which have closed circulatory systems). The tongue of this class is referred to as a radula. Examples of Mollusca include clams, snails, squids, and octopuses. D. Echinodermata Echinodermata have a complete digestive system; therefore the answer choice is incorrect. They are triploblasts with radial symmetry as adults), and are coelomates with open circulatory systems. They are deuterostomes (like Chordata). Examples of Echinodermata include starfish, sea urchins, and sea cucumbers. E. Platyhelminthes Platyhelminthes do not have a complete digestive system, so the answer choice is correct (it is important to know that Cnidaria also lack a complete digestive system - both Cnidaria and Platyhelminthes instead have a gastrovascular cavity in which two way digestion takes place, rather than the one way digestion through an alimentary canal seen in other classes with digestive systems). Platyhelminthes are triploblasts with bilateral symmetry, and are acoelomate. Examples include flatworms, tapeworms, and flukes.
Where is ADH stored in the body
ADH is produced in the hypothalamus. The posterior pituitary stores oxytocin and ADH (also known as vasopressin). The pineal gland produces melatonin to help regulate our sleep patterns. The anterior pituitary produces the following, you can remember most of them with the acronym FLAT, for: FSH, LH, ACTH, and TSH. A. Thyroid The thyroid does not store ADH; therefore the answer choice is incorrect. The thyroid is located just in front of the trachea and is responsible for the production of thyroxine (T4) and triiodothyronine (T3), which increase metabolic rate, and calcitonin, which lowers blood calcium ion levels. B. Pancreas The pancreas does not store ADH; therefore the answer choice is incorrect. The pancreas is both an exocrine and endocrine gland and has bundles of cells called islets of Langerhans. Alpha cells of the pancreas secrete glucagon, a catabolic hormone that converts glycogen to glucose and raises blood glucose levels. Beta cells of the pancreas secrete insulin, an anabolic hormone that converts glucose to glycogen and lowers blood glucose levels. Delta cells of the pancreas secrete somatostatin, which inhibits the release of insulin, glucagon, and other gastrointestinal hormones. C. Pineal gland The pineal gland does not store ADH; therefore the answer choice is incorrect. The pineal gland (located in the brain) secretes melatonin, which plays a role in maintaining the circadian rhythm, including the timing of sleep. D. Posterior pituitary The posterior pituitary stores ADH and oxytocin produced by the hypothalamus, so the answer choice is correct. It is important to note that the posterior pituitary itself does not synthesize these hormones - the neural cell bodies of the hypothalamus synthesize them, then they are transferred down axons to the posterior pituitary for storage and release into the blood. For reference, ADH stands for anti-diuretic hormone (anti-diuretic meaning you don't urinate as often), and can also be referred to as vasopressin. When you drink coffee or beer you may urinate more often, these are known as diuretics. E. Anterior pituitary The anterior pituitary does not store ADH; therefore the answer choice is incorrect. The anterior pituitary is responsible for releasing the tropic hormones (hormones that stimulate other endocrine glands) ACTH, TSH, LH, and FSH and the non-tropic hormones (hormones that stimulate their target organ directly) HGH, prolactin,MSH (melanocyte stimulating hormone), and endorphins. The anterior pituitary is often regulated by the hypothalamus. You can remember the hormones released by the anterior pituitary with the mnemonic "FLAT PiG" (FSH, LH, ACTH, TSH; Prolactin and Growth hormone).
Acetylcholinesterase
Acetylcholinesterase is found in nerve and muscle tissue, central and peripheral tissues as well as sensory and motor fibers -This Enzyme hydrolyzes the neurotransmitter acetylcholine -Acetylcholine is released by the nerve into the synaptic cleft where it binds to ACh receptors on the post synaptic membrane allowing for nerve transmission -Acetylcholinesterase breaks acetylcholine down to terminate signal transmission and is also located on the post - synaptic membrane
Fish Types
All fish have gills. Modern of fish are Agnatha (primitive, jawless: include Lampreys and hagfish), Chondrichthyes(Jawed fish that have cartilage skeletons), and Osteichthyes(Jawed fish that have skeletons made of bone). They are cold-blooded vertebrates who respire by passing oxygenated water over gills.
What is the Cell Theory
All living organisms are composed of one or more cells The cell is the most basic unit of life All cells come from pre-existing, living cells Modern cell theory has expanded on these fundamental statements, and can best be summarized in the following seven statements: All known living things are made up of one or more cells All living cells arise from pre-existing cells by division. The cell is the fundamental unit of structure and function in all living organisms. The activity of an organism depends on the total activity of independent cells. Energy flow (metabolism and biochemistry) occurs within cells. Cells contain DNA which is found specifically in the chromosome and RNA found in the cell nucleus and cytoplasm. All cells are basically the same in chemical composition in organisms of similar species
classifications
Amphioxus is an invertebrate. Amphioxus and tunicates are chordates that are not vertebrates. Chordates have a notochord at least sometime during development, however, the amphioxus and tunicates do not lose their notochord -invertebrates include mollusks, arthropods, annelids, and echinoderms -monkeys, apes, and man are all primates -a viviparous mammal is one in which the offspring develop within the uterus -a duck-billed platypus is an egg laying mammal
What is colchicine
An alkaloid that inhibits the polymerization of tubulin into microtubules. Microtubules and associated proteins comprise the mitotic spindle. Mitosis would stop of Colchicine is present.
amnion
An amnion is a membrane that surrounds an embryo or fetus and is filled with a watery solution. This can act as a shock absorber to protect the developing ani- mal, as well as to prevent dehydration. It evolved in organisms that no longer have an aquatic life-style. A frog lays eggs in the water, so the eggs need no specialized water-filled membrane to keep them from drying out.
All of the following directly use an electrochemical gradient EXCEPT one. Which one is the EXCEPTION? A. Flagella rotation B. Mitochondria C. Chloroplasts D. Aquaporins E. Neurons
An electrochemical gradient is one where an electrochemical imbalance exists between a membrane. A great example is a proton gradient in ATP synthesis. Protons are pumped out of the mitochondrial matrix to create a proton force made of electrical charge (protons are positively charged) and a chemical gradient (made up of H+), or an electrochemical gradient. Flagella use proton force to spin and give locomotion to bacteria. Mitochondria use a proton force in ATP synthesis as well as chloroplasts, where they also produce NADPH. Neurons use Na+/K+ ATPase to create an electrochemical gradient by pumping 3 sodium ions out of the cell and 2 potassium ions into the cell. Aquaporins are protein structures in the membrane that help water passively flow into or out of the cell, a process known as facilitated diffusion. A. Flagella rotation In prokaryotes, the flagella uses a proton motive force to spin and give locomotion. This proton motive force makes of the flow of protons (hydrogen ions) across the bacterial membrane - this is an electrochemical gradient; therefore the answer choice is incorrect. B. Mitochondria Mitochondria must establish an electrochemical gradient in order to produce ATP; therefore the answer choice is incorrect. When NADH and FADH2 are oxidized in the electron transport chain, protons are transported from the mitochondrial matrix to the intermembrane space. This creates an electrochemical gradient within the mitochondria; ATP synthase utilizes the kinetic energy established by this electrochemical gradient to produce ATP as protons flow from the intermembrane space into the mitochondrial matrix. C. Chloroplasts Chloroplasts use an electrochemical gradient to produce ATP; therefore the answer choice is incorrect. During photolysis and the transfer of electrons from photosystem II to photosystem I, protons accumulate in the thylakoid lumen of the chloroplast. This establishes an electrochemical gradient within the chloroplast; ATP synthase utilizes the energy established by this electrochemical gradient to produce ATP as protons flow from the thylakoid lumen out into the stroma. D. Aquaporins Aquaporins are integral membrane proteins that allow for the facilitated diffusion of water across the cell membrane. The only gradient involved in facilitated diffusion is movement down a concentration gradient, not electrochemical, so the answer choice is correct. E. Neurons Neurons are the functional unit of the nervous system. The membrane of neurons are maintained at resting potentials with an electrochemical gradient consisting of a higher concentration of K+ inside the cell and a higher concentration of Na+ outside the cell, and an overall excess of negative charge inside the cell relative to the outside; therefore the answer choice is incorrect. This gradient acts as a means of transmitting nerve impulses - voltage-gated channels opening allows for the movement of Na and K across the membrane, resulting in an action potential.
About plants
Angiosperms are flowering plants. They are divided into monocots (narrow leaves like grass) and dicots (broad leaves like shrubs) . Undifferentiated cambium tissue develops into phloem and xylem (vascular tissue). Xylem transports water and minerals up the stem while the phloem transports nutrients down the stem. Plants lacking vascular tissue are called non-tracheophytes: these include simple plants. Gymnosperms do not have flowers ex: redwood, pine, juniper tree (a fruit is the ripened ovary of a flower)
about plants
Angiosperms are the most diverse types f plants; they are flowering plants A cotyledon or seed leaf will store food for the germinating seedling Endosperm will serve as food for a flowering plant embryo, and later for the germinating seedling Vegetative propagation is a form of asexual reproduction in plants Vegetative Propagation is a form of asexual reproduction. One of the sperm cells unite with the egg to form a zygote. The nucleus of the second sperm unites with 2 polar bodies to form a 3N cell. The 3N cell develops into specialized endosperm tissue. This "double fertilization" occurs only in flowering plants, the angiosperm
Hormones and sites of production
Anterior Pituitary: HGH, LH, FSH, TSH and prolactin Posterior pituitary only stores ADH(vasopressin) and Oxytocin. Both are made in the hypothalamus Adrenal cortex makes aldosterone and cortisol while the adrenal medulla makes epinephrine (adrenaline) and norepinephrine (noradrenaline) Glucagon is made by the pancreatic alpha cells while insulin is made by beta cells Glucagon and cortisol raise glucose levels in the blood while insulin lowers glucose levels Aldosterone is involved in Na+ reabsorption and K+ secretion in the kidneys collecting duct as well as a raise in blood pressure and blood volume Epinephrine: vasoconstriction of blood vessels Parathyroid: increases blood calcium
about antibodies
Antibodies are proteins that are in five major classes: IgG, IgM, IgA, IgE and IgD. IgG: most abundant circulating antibody IgM: the first antibody to appear in response to an antigen IgA: found in saliva, sweat and tears and prevents viral and bacterial attachment to epithelial surfaces IgE: involved in allergic reactions IgD: does not cross the placenta and is found on the surface of B cells. Involved in the differentiation of B cells into memory and plasma cells.
What is ecological succession
Areas in which communities replace one another ex: sand dunes become woodlands, ponds become grasslands or even deserts
fertilization
Around the sixth day the blastocyst begins to attach to the endometrium of the uterus. About 24 hours after fertilization in the fallopian tube, the zygote undergoes mitosis giving rise to 2 daughter cells. These cells, in turn, divide into 4 cells, then 8 then 16 and so forth. With each subsequent division, the cells become smaller and smaller. This is called cleavage. After about 3 days, a solid ball of about 32 cells form; it is called a morula. The embryo does not grow during cleavage. The morula cells continue to divide for 4 days to form a blastocyst that implants in the uterus. This implantation in the uterus (endometrium) occurs on day 6xth day,
blood
Artery constriction will increase blood pressure while dilation will decrease blood pressure Normally arteries carry blood high in O2 while veins are low in O2 Pulmonary arteries and veins are opposite of the systematic circuit Pulmonary arteries are low in O2 while pulmonary veins are high in O2 veins often have valves and have the same 3 layers as an artery but the wall is much tinner Blood moves the slowest in the capillaries due to greatest total cross sectional area
about fatty acids
B-Oxidation of fatty acids occurs in the matrix of the mitochondria whereas fatty acid synthesis occurs in the cytosol Fatty acids are metabolized into acetyl CoA units which can then enter the citric acid cycle to generate ATP. Animals cannot convert fatty acids into glucose. Specifically, the Acetyl CoA produced will enter the TCA (citric acid) cycle
The phenomenon by which WBC adhere to and pass through the endothelium of the blood vessels is called:
B/c of diapedesis, white blood cells become a part of the interstitial fluid. WBC slip through the tiny endothelial pores that widen in response to the presence of "injury producing" chemicals during an infection of traumatic injury. Neutrophils, leukocytes, and cytokines are the cells primarily involved in diapedesis with the neutrophils the first cell type to arrive. Chemicals like prostaglandins and histamines are released by the injured tissue cells: this causes vasodilation and an increase in capillary permeability. An increase in blood flow occurs as well allowing the WBC to consume pathogens
About Bacteria
Bacteria are prokaryotes that reproduce by binary fission. Most bacteria have a single circular chromosome that is replicated; many species also have plasmids. Surface appendages called pili allow bacteria to adhere to one another or even to a mucous membrane. Pili hold bacteria together to allow DNA transfer during conjugation
About bacteria
Bacteria can start a process called endo sporulation where an endospore is produced. Endospores are resistant to extreme temps, chemicals, toxins, detergents, and radiation. Microorganisms can adapt to environmental changes thus the production of endospores is a survival strategy employed by certain gram-positive bacteria under extreme conditions. The cell wall of bacteria is up of peptidoglycan while plant cell walls are made of cellulose. Endospore is made of bacterial cytoplasm, DNA and is surrounded by a tough outer coat
Marine Zones
Benthic zone: bottom surface of sea floor Pelagic zone: open waters of any depth Aphotic Zone: no photosynthetic plants. No light reaches this area Intertidal Zone: land meets water Photic Zone: Light and photosynthesis is seen ex: Zooplankton
About Kidney Physiology
Blood enters the glomerulus via the afferent arteriole and leaves via the efferent arteriole. If efferent arteriole is constricted blood cannot flow past the constricted point. This causes an increase in the glomerular pressure as blood backs up into the glomerulus consequently the glomerular hydrostatic pressure is increased and filtration rates rise. The opposite will occur is the afferent arteriole is constricted: blood flow is diminished, hydrostatic pressure is decreased and filtration decreased. Sympathetic innervation of the kidneys primarily will affect the afferent arterioles and causes constriction and would reduce the urine output.
Pulmonary Vein
Blood enters the heart on the right side, from the superior and inferior vena cava. This blood is deoxygenated. It circulates from the right atria to the right ventricle, then goes out through the pulmonary artery to the lungs. At the lungs, the blood disposes of CO2 and absorbs O2 and then returns to the heart through the pulmonary vein. Therefore the blood in the pulmonary vein should be high in O2, or answer choice [C]. The terms "vein" and "artery" only describe if blood is moving towards or away from the heart, it has nothing to do with whether they're oxygenated or not. The pulmonary artery has a low concentration of oxygen and the pulmonary vein has a high concentration of oxygen.
About Spleen and Lymphs
Blood is composed of white blood cells that include neutrophils, lymphocytes, monocytes, basophils, and eosinophils. Neutrophils make up about 60% of white blood cells while lymphocytes make up about 30%. Lymph is a tissue fluid that contains water, proteins, salts, sugars, and urea. The lymphatic system returns excess interstitial fluid to the blood. It also absorbs fats and fat-soluble vitamins from the digestive system and transports them to the venous circulation. It also provides defense from microorganisms. Lymph nodes filter the lymph to remove foreign invaders. Lymphatic organs like the spleen contain lymphocytes that destroy invaders, make lymphocytes, filter blood, store red blood cells and destroy old ones.
structure similar to chlorophyll
Both chlorophyll and heme (part of hemo- globin) contain a porphyrin ring. None of the other answer choices have a similar structure.
about heart
Both superior and inferior vena cava carries deoxygenated blood from the upper and lower extremities to the right atria
After ejaculation, what process must sperm undergo before they are competent to fertilize an oocyte?
Capacitation is the penultimate step of development of sperm. It occurs in the oviduct. It involves the destabilizing of the acrosome to allow for better binding between the sperm and oocyte. The acrosome reaction is when the tip of the sperm reacts with the zona pellucida of the egg to fuse together. Metamorphosis is the process of additional development that usually refers to the process of larva turning into an adult insect. Sperm meiosis is completed in the seminiferous tubules.
Catabolism
Catabolism is the breaking down of materials to smaller units, such as when glucose is broken down to release energy. If we're breaking down glucose, we're releasing energy, so this is an exergonic reaction. It is the opposite of anabolism, a set of metabolic pathways to create molecules from smaller units. Think of anabolic steroids, they develop bigger muscles because they build up molecules. It takes energy to build up those muscles, so anabolism is an endergonic process.
about some prokaryotes
Cell wall is made of peptidoglycan. Peptidoglycan is composed of polysaccharide and polypeptide chains. Gram positive bacteria have a thick peptidoglycan layer and appear purple after gram staining. the thin peptidoglycan layer of bacteria causes most of the gram stain to be washed off. Blue-green algae are the cyanobacteria and have cell walls. Teichoic acids are used as recognition and binding sites by bacterial viruses that cause infection. These acids are in gram-positive bacteria and covalently attached to the peptidoglycan layer.
about breathing
Chemoreceptors are specialized structures located in the walls of major arteries. They detect changes in H+, O2, and CO2. breathing is sensitive to blood CO2 and H+ ion concentrations. A small inc in H+ or CO2 will increase the breathing rate. High blood O2 partial pressure would decrease breathing rate
stomach cells that produce pepsinogen
Chief cells: secrete pepsinogen pariental cells: secrete HCl, intrinsic factor (B-12 absorption) G-cells: secrete hormone gastrin which stimulates HCl production of parietal cells Mucous cells: secrete mucous that lubricates the stomach and protects the stomach from HCl production
A situation in which different body cells express different genotypes and all cells are derived from different fertilized eggs is called a
Chimera
About Chitin
Chitin is a polysaccharide that has glucose molecules with nitrogen groups attached. It is a polymer of amino sugars and is found in the cell walls of fungi and exoskeleton of arthropods.
Which statement best explains why some sea birds can drink seawater but humans cannot? A. Their intestines are physically designed to filter salt from their diet. B. Sea birds naturally have a higher intracellular osmolarity that requires excessive amounts of salt from their diet. C. Salt glands secrete the excess salt. D. Their nephrons are adapted to be longer to resorb less sodium to compensate for the excessive salt intake. E. Specialized bacteria in sea bird's intestines utilize the salts before the sea bird can absorb them.
Choice [A] is wrong because there is no structure in the intestine that can physically eliminate salt. Choice [B] is wrong because most chordates have similar osmolarities. Choice [D] is incorrect because nephrons become longer to resorb MORE ions and water, not less. A classic example are rodents in the desert that have very long loops of Henle to resorb as much water and ions as possible. Lastly, specialized bacteria will still eliminate the salts after they've used them, so it does not solve the problem of excessive salt. Choice [C] is correct, sea birds have supraorbital glands, or salt glands, above their eyes, which secrete excess salt from their blood. It functions similar to a kidney, but is much more efficient at excreting salt.
which hormone stimulates release of bile
Cholecystokinin is a hormone made by cells of the duodenum(first part of the small intestine) that stimulate bile release Some duodenal cells produce the hormone secretin, which stimulates the production of pancreatic juice, especially the bicarbonate portion. Gastrin is made in the stomach. This hormone stimulates HCl secretion. Enterogastrone is made in the duodenum and when fatty food is in the intestine it inhibits stomach glands secretion and slows the stomachs muscular movemnt. By slowing the stomach's emptying, more time is allowed for meals that contain fat to digest
phylums
Cnidaria: Hydras, corals, jellyfish Arthropoda: spiders and crustaceans Chordata: Tunicates, mammals, amphibians Chordata: reptiles, jawless fish
Categories
Coelomates: animals with true coelom (body cavity) lined by tissue that is derived from the mesoderm Pseudocoelomates: cavity that is not completely lined by tissue derived from the mesoderm Acoelomates: lack a cavity between their gut and outer body wall Vertebrates, Annelids, and Arthropods: Coelomate Pseudocoelomates: Roundworms (nematodes) Acoelomate: Platyhelminthes
A chemical defense system that works with the immune response and supplements the inflammatory response is termed
Complement system
glucocorticoids
Cortisol: isolated from the adrenal cortex and promotes the synthesis of glucose from sources like proteins
Which of the following statements accurately describes cytokinesis in mammals?
Cytokinesis is the last stage of mitosis and actually begins occurring at the end of anaphase. It is the process of dividing the cytoplasm to form 2 cells. In mammals, a cleavage furrow develops from microfilaments encircling the cell and pulling the plasma membrane into the center. In plants, vesicles from the Golgi bodies migrate and fuse to form a cell plate to separate the two cells (Choice B). Choice [A] is incorrect, molecular chaperones are typically used in protein synthesis, not in cytokinesis. Choice [D] refers to anaphase directly where the microtubules shorten to pull apart chromosomes. Choice [E], while true, is not related to cytokinesis.
genetics
DNA synthesis is during S phase In G2 phase, the cell prepares to divide In G1, we see the production of mitochondria, ribosomes, and much protein synthesis Ribosomes are assembled by the nucleolus
cells
Desmosomes hold adjacent cells together Desmosomes attach cells together and give cells mechanical strength and are abundant in cells such as skin. Tight junctions seal the spaces between cells and prevent cell leakage. Intestinal cells are surrounded by tight junctions that prevent any intestinal content to seep out. The gap junction will allow cells to exchange nutrients for "molecular communication" The fluorescent tag was able to move into the adjacent cell due to the gap junction
facts
Determinate cleavage is characteristic of protostomes such as mollusks, annelids, and arthropods In protostomes, the blastopore forms the mouth while in deuterostomes the blastopore forms the anus In determinate cleavage, if after the single cell divides and the cells are separated from each other, they will die. There is no potential to develop into a viable organism. During the indeterminate (regulative) cleavage, if the cells are separated they can develop into a viable organism.
Deuterostomes and Protostomes Differences
Deuterostomes and Protostomes are classifications of animals that differ in their development of the mouth and the anus. The blastospore or the opening in the archenteron (the primitive gut that forms during gastrulation) gives rise to the anus in deuterostomes. In protostomes, the blastospore evolves to become the mouth of the embryo. The cleavages (cell divisions in the zygote's early development) of protostomes are spiral and determinate. In deuterostomes, they are radial and indeterminate. The coelom develops from splitting of mesoderm tissue at the sides of the archenteron in protostomes. In deuterostomes, the coelom develops directly from outpouching in the archenteron wall. The blastopore gives rise to the mouth in protostomes and the anus in deuterostomes.
What is unique to angiosperms
Double fertilization of the egg nucleus and of the central nucleus. One sperm nucleus fertilizes the egg, we form a 2N zygote. Now, the other sperm nucleus fertilizes the two haploid central nuclei forming a 3N endosperm nucleus that is a nutritive tissue. The endosperm will provide nutrients to the developing embryo.
Calcium in Muscles cells
During a muscle contraction, a neuron releases acetylcholine which triggers an action potential on the muscle cell. This signal is propagated by T tubules and releases Ca2+ from the sarcoplasmic reticulum and initiates contraction of the muscle cell. The calcium binds to actin filaments called troponin, which allows it to change its shape and expose binding sites for myosin. The myosin binds to the actin by using ATP and shortens, creating a contraction. When the action potential passes, the calcium gets removed from the troponin and the binding sites are no longer available, relaxing the cell.
About lakes and ponds
During the summer, warm water is at the surface and is well aerated because of oxygen productoin by plants and mixing by the wind. The bottom layer is high in nutrients. In the spring and autumn, oxygenatted water from the surface goes to the bottom and nutrients from the bottom go to the top. This is called turnover
what protein is associated with a flagellum
Dyne is the "motor protein" Energy contained in ATP is converted into energy used for movement Dynein is also involved in chromosomal movement During cell divsion, chromosomes are moved into proper position with the aid of dynein
About Ebola
Ebola infects white blood cells like monocytes and macrophages along fibroblasts, dendritic cells and endothelial cells that release proteins that can cause clots in the bloodstream
What syndrome is not due to trisomy nondisjunction
Edward Syndrome, Down syndrome, and Klinefelter syndrome are because of trisomy nondisjunction Turner's syndrome is monosomy of having only XO
which hormone inhibits peristalsis and acid secretion by the stomach
Enterogastrone is released by the duodenum to inhibit peristalsis and acid secretion by the stomach Cholecystokinin causes the gallbladder to contract, it is also made in the duodenum Secretion signals the pancreas to release bicarbonate (a buffer) which can neutralize the acidic chyme Secretin is also made by the duodenum
about enzymes
Enzymes are globular proteins that will lower the energy of activation. They do not alter H, G, or K. Feedback inhibition is used to regulate a metabolic pathway. Here we see a product come back to inhibit an enzyme that was used in a previous reaction. Many, if not most enzymes operate with some type of a feedback mechanism. Feedback inhibition allows for an entire reaction series to be shut down.
Organisms
Euglena: has flagellum for locomotion and has chloroplasts, lives in fresh water, lack a cell wall and are highly motile ciliated protozoa: Paramecium: relies on contractile vacuoles to rid of excess water Planaria : flatworm and contains both male and femlae reproductive structures; planaria excretory system is composed of a network of tubular excretory canals that open to the outside of the body and contain flame cells that are involved in fluid excretion Hydra: multi celled organism that contains tentacles with specialized stinging cells called nematocysts
facts
Exchange of oxygen and carbon dioxide between mother and fetus occurs through the placenta. Maternal blood pools in sinuses in the placenta, and umbilical ves - sels are in close contact with the sinuses. Gas exchange occurs across the wall of the umbilical vessels in a fashion similar to gas exchange across the walls of the pulmonary capillaries and alveoli in the lungs. The allantois (choice A) ultimately becomes the umbilical cord, the chorion (choice D) is a membrane formed from the 8 initial tissues that penetrate the endome - trium (the trophoblast), and the yolk sac (choice E) is the site of formation of the first red blood cells. There is no such thing as a chorioallantoic membrane (choice C).
which lack seeds
Fern is a vascular plant that contains xylem and phloem tissue. They reproduce by spores. Ferns lack seeds and flowers. The life cycle is referred to as alternations of generations which include a sporophyte and gametophytic phase. Angiosperms and gymnosperms are seed producing plants.
about WBC
Five major leukocytes: monocyte, neutrophil, lymphocyte, basophil, eosinophil Neutrophils are most numerous and basophils are least numerous
The breakdown of which of the following products does not produce glucose?
Fructose is an isomer of glucose, so break - ing down fructose could not produce glu - cose. Glycogen and cellulose (choices B and C) are large polymers of glucose. Sucrose and maltose (choices D and E) are disaccharides, one monomer of which is glucose (sucrose = glucose + fructose, maltose = glucose + glucose).
Hardy Weinberg Equilibrium
Genetic Equilibrium possible if the population was very large and no net mutations, random mating occurred, isolation from other populations and no natural selection occurred. Bottlenecking will reduce overall genetic variability while founder effect introduces new genes. Meiosis will not change the Hardy-Weinberg eq. because the genetic frequency is not altered for the genes to keep going back into the gene pool.
stem elongation and flowering in some plants are due to
Gibberellins are plant hormones that induce certain plants to flower and allow stem elongation. Ethylene stimulates stem ripening. Abscisic acid is an inhibitor of plant growth hormones. Cytokinins are plant hormones involved with promoting cell division
about PNS and CNS cells
Glial cells include astrocytes, Schwann cells, and oligodendrocytes. The Glial cells provide support and protection as well as myelin production. Schwann cells are glial cells of the PNS while Oligodendrocytes are glial cells of the CNS. Both cells make myelin. Astrocytes are the most abundant glial cells in the CNS. These cells are involved in maintaining brain homeostasis among other functions such as regulating glucose and oxygen delivery in neurons
about Kidney physiology
Glomerular filtrate is larger water and contains same substances as blood plasma except for large proteins Glomerular filtrate contains water, glucose, urea, amino acids, and ions like K+, Na+, Cl- Blood pressure forces water and solutes out of the glomerular capillaries and into the region inside Bowmans capsule (lumen) The first step in urine formation is filtration through the glomerulus into Bowmans Capsule
Glycolysis
Glycolysis requires the use of energy when the glucose molecule is broken into two pyruvates. The two steps in which ATP is used can be considered endergonic, however, overall glycolysis produces energy to be consumed by the cells. If energy is released, then the reaction is exergonic.
Bone
Ground substance is the gel like noncellular portion of the extracellular matrix. Fibers, glycoproteins, proteoglycans, and glycosaminoglycans can be found. Fibroblasts produce the ground substance, not osteocytes. Osteocytes are entrapped in the bone matrix and are involve with regulating bone health
immune system
Histamine is a vasodilator contained in basophils and mast cells Macrophages produce a cytokine called Interleukin-1 while helper T cells are produced Interleukin 2 Interleukins can activate cytotoxic cells, B cells, and other helper T cells Helper T cells mobilize both humoral and cell mediated branches of the immune system
genes that regulate anatomical structures in insects, plants and mammals
Homeotic genes: involved in building organs and body parts Genes encode various proteins known as transcription factors that direct cells to form various anatomical parts like wings, antennae, and legs
allantois
In mammals, the chorionic villi eventually form the placenta, but the villi are finger-like sections that burrow into the wall of the uterus near the mother's blood vessels. The allantois disposes of wastes, and forms part of the umbilical cord to carry waste away from the embryo and towards the mother's blood vessels. The amnion is a thin sac that surrounds the embryo and produces amniotic fluid to provide cushion for the growing embryo. Mammals do not have yolk, and the yolk sac contains only fluid to cushion the growing embryo and has blood vessels in it that give rise to the vascular system of the embryo. In birds, the yolk sac serves to nourish the embryo throughout its development.
smoking
In response to smoking, cilia are damaged and mucus produced by the goblet cells is increased. The lungs have a decreased means of moving the mucus out, thus an unproductive cough results. Continued smoking may lead to chronic bronchitis, emphysema or lung cancer.
process in an embryo in which one tissue causes another to differentiate is called:
Induction it is seen during gastrulation
Interferon
Interferons are a group of small proteins made by most body cells following a viral attack. They belong to a class of glycoproteins called cytokines Interferons are also produced in response to bacterial, parasitic, and foreign agents as well as tumor cells
about cells
Interns are cell adhesion molecules. they couple the extracellular matrix from the outside to the inside of the cell (cytoskeleton). integrins are heterodimers of alpha and beta subunits. these cell surface receptors that interact with the extracellular matrix are responsible for the mediation of intracellular signals. Wound repair is a critical event for our survival, the process of wound coverage is called re-epithelialization which can occur about 24 hours after trauma. Integrins help mediate the movement of epidermal cells into the area that was injured. this is but one of many examples in which integrins play a major role in cell signaling
Lysosomes
Involved in digestion of substances brought into the cell which contains many enzymes some enzymes end in -ase
Second messenger molecules
Involved in the relay of a signal at receptors on the cell surface to target molecules in the cytosol and/or nucleus. Includes: IP3, DAG, cyclic AMP, cyclic GMP, and Ca2+
Humoral immunity
Is responsible for the production of immunoglobin or antibodies. The antibody will bind to the antigen (foreign particle) and attempt to destroy it. T-lymphocytes are involved in cell mediated immunity. T-lymphocytes do not make antibodies. B lymphocytes make antibodies
Lydia cells and islets of langerhans
Islets of Langerhans represent a collection of alpha and beta cells of the pancreas. the alpha cells secrete glucagon and he beta cells secrete insulin Leydig cells in the testes secrete testosterone
About the sodium Potassium Pump
It is an integral protein. Actively pumps 3Na+ out of a cell and 2K+ into a cell against their gradients by using ATP. Drugs like ouabain or digitalis will stop the pump and cause the buildup of Na+ in the cell.
evolution
Jawless dish -> bony fish -> reptile s-> amphibians -> birds -> mammals A Real Bad Man Amphibians , reptiles, birds, mammals
matching
Joints : auctions between bones Femur: longest bone in the body knee is a hinge joint which allows movement in one plane only -ball and socket joints include the hip and shoulder; they allow movement in all planes -ACL ligament is one of four ligaments connecting the bones of the knee joint. this ligament will connect the femur and tibia -ACL ligaments limit rotational knee movement. This ligament is common injury in athletes
R-selected populations
K selected = members have low reprouctive rates and are roughly constant in size ex: humans R selected = bacteria, rapid growth, numerous offspring, fats maturation and little parental care
Keratin
Keratin is a fibrous protein that is found in mammals, birds, reptiles, and amphibians. Cells in the skin are almost waterproof due to keratin. Keratin is found in nails, hair, skin, hooves, claws, horns, and even the shell of a turtle.Keratin can be soft V(feathers) or very hard (turtle) due to the disulfide bridges.
Genetic disorders
Klinefelter syndrome: 44 autosomes and XXY Turner Syndrome: Sterile female lacking X chromosomes Down Syndrome: 47 chromosomes Hemophilia: sex linked disorder
Part of prokaryotic cell
Lack organelles like mitochondria, golgi bodies, ER, nucleus, and lysosomes. They do contain ribosomes, nucleic acids, plasma membrane, and nuclear region called a nucleoid
Ligand gated channels
Ligand gated channels are controlled by a substance present in the extracellular fluid to the receptor An excited neuron releases acetylcholine into the synaptic cleft. It is in the postsynaptic neuron that acetylcholine interacts with the acetylcholine receptor and triggers an impulse Binding causes a conformational change that opens the channel The acetylcholine is the ligand. Now, Na+ rush in, K+ move out; the Na+ influx depolarizes the postsynaptic membrane, initiating an action potential Voltage gated channels such as K+ and Na+ are controlled by the voltage across the membrane due to concentration gradients of ions
insulin acts as a ? by binding and triggering a conformational change within subunit receptors
Ligands bind to and form a complex with biomolecules such as receptors The conformational site of a receptor is altered upon binding. Ligands include substrates, activators, inhibitors, hormones, and neurotransmitters
An unknown biological sample is exposed to several enzymes and is found to react only with lipase. What is this sample composed of?
Lipases are enzymes that digest fats. Adipose tissue is also known as body fat. Fats are made of triglycerides, which contain a glycerol backbone and fatty acid chains, which make up lipids. You could conclude that lipases likely digest lipids given their similar names. Nucleic acids are what DNA and RNA are made of, and are digestible by nucleases. Glycogen stores are long chains of glucose molecules. Skeletal fragments are bones and made of bone matrix, an organic and inorganic mixture. Actin and myosin make up muscles and are made of proteins.
About White blood cells
Lymph nodes contain B cells, T cells, and macrophages. Large macrophages contain fibril-like pseudopodia that can attach to a bacterium. Macrophages are the largest phagocytic cells and will phagocytize bacteria. Fixed macrophages are very numerous in lymphatic organs like the spleen and lymph nodes. Neutrophils have an average lifespan of a few days and tend to self-destruct as foreign invaders are destroyed. Neutrophils make up about 60% of white blood cells
Urination
Mammals and adult amphibians excrete urea, while marine animals excrete ammonia. Birds, insects, and reptiles excrete uric acid. Uric acid requires little water for its excretion and actually forms a precipitate. The vasa recta is a capillary system associated with the loop of Henle and is involved in concentrating the urine
plants
Mature xylem and sieve tube cells have no nucleus. The sap of a plant is transported by sieve cells. Parenchyma cells carry out metabolic functions in the plant such as synthesis of organic compounds. The photosynthetic cells in a leaf are actually parenchyma cells. Parenchyma cells do not have a nucleus Secondary xylem make up most of the wood in a tree CO2 enter the leaf and Oxygen exits by the stomata
If a human cell has 46 chromosomes at the beginning of meiosis, then at the end of meiosis I each cell would have: A. 23 chromatids B. 46 chromatids C. 46 chromosomes D. 92 chromatids E. 92 chromosomes.
Meiosis will take a diploid cell and produce two haploid cells. This means that our chromosome number will decrease to 23 chromosomes for each daughter cell. However, each of these chromosomes have two chromatids, so they will also have 23 x 2 = 46 chromatids.
The epidermis is the outermost layer of the integumentary system and is comprised of four types of cells. Which of the cell types is associated with fine-touch differentiation necessary for detecting shapes and texture?
Merkel cells are oval shaped and usually can be found in clusters under ridged epidermal areas. These are the cells responsible for fine-touch differentiation. Keratinocytes produce keratin and are the cells responsible for creating the skin barrier against infection. Fibroblasts manufacture collagen and are found in the dermal layer since collagen is one of the connective tissues. Melanin, the pigment responsible for skin color, is produced by melanocytes. The function of the Langerhans' cell is to fight against skin infection by processing microbial antigens.
Connective Tissue binds and supports different types of tissues and organs. Which germ layer is it derived from?
Mesoderm. Consists of various cell types like fibroblasts, mast cells, and macrophages. Some connective tissue like bone and cartilage are rigid whereas adipose tissue and fibrous tissue are flexible
Competitive Inhibition
Metal cofactors and ATP are often used to help boost enzyme activity, and are not competitive inhibitors. Non-competitive inhibition (D) occurs when an inhibitor is able to prevent the enzyme from binding with the reactant by binding to the enzyme at a site away from the active site, and change the enzyme's conformation so it cannot bind to the reactant. Competitive inhibition occurs when the inhibitor competes directly with the reactant at the active site, and this substrate takes the place of the reactant and prevents the reaction from occurring.
terms
Metaplasia: a change form one cell type to another such as inflammation or irritation Hyperplasia: refers to an increase in cell numbers Hypertrophy: refer to an increase in the cell size of a tissue or organ Atrophy: refer to a decrease in cell size Aplasia: refers to almost complete failure of development
some facts
Mg2+ is found in chlorophyll Fe2+ is found in hemoglobin the stinging cells of cnidarians are called nematocytes ribosomes are found in prokaryotes and eukaryotes Cnidoblasts are specialized cells located in the tentacles and body wall of coelenterates. The interior is filled by the stinging cells, nematocytes
Layers
Morula is a solid ball of cells. Morula divides mitotically to form a hollow ball of cells called a blastula. Blastula becomes the gastrula Ectoderm: hair, eyes, teeth, skin, nervous system, lens of the eye Mesoderm: skeleton, muscles, gonads, kidney, and circulatory system Endoderm: lining of bladder, digestive and respiratory tracts, liver, pancreas, gall bladder
An area located close to the equator of an egg on the side opposite the point of sperm entry is called:
Most animal cells have polarity. In animals and many frogs, the yolk is most concentrated in the vegetal pole and least concentrated in the animal pole. When some ectodermal cells elongate, the neural plate is formed. The folding of the neural plate gives rise to the neural tube that will become the brain and spinal cord. The gray crescent will establish the body axis and is an area located on the side of the egg opposite the sperm penetration
Digestive Enzymes
Mouth: salivary amylase (carbohydrates) Stomach: Pepsin (proteins) Pancreas: pancreatic amylase (carbohydrates), pancreatic trypsin and chymotrypsin (proteins), carboxypeptidase (proteins), nucleases (DNA, RNA), lipase (fats) [Note: these digestive enzymes are secreted by the pancreas but carry out their function in the small intestine] Small Intestine: Disaccharidases (carbohydrates), dipeptidases and aminopeptidases (proteins), nucleotidases (nucleotides), nucleosidases (nucleosides)
Matching
Myelin is made by schwann cells. Myelin acts as an electrical insulator; it increases the rate in which the axon can translate signals. Gluconeogenesis occurs in the cytosol Nerve signal is Presynaptic cleft -> synaptic cleft -> postsynaptic cleft Middle ear has 3 bones: incus, malleus, and stapes Inner ear has semicircular canal for balance and snail-like cochlea where sound waves in the air are converted into neural messages
What is the fundamental niche of an organism?
Note that this question asks about the "fundamental niche" of an organism, not just the "niche". The fundamental niche of an organism is simply the range of environmental conditions an organism can live in, where there is no influence from predators. The realized niche is where the organism actually lives in the environment.
what lacks a notochord
Notochord is a cartilaginous rod that extends from the head to the tail in the embryo of all chordates The notochord is derived from cells of the mesoderm Earthworm is an invertebrate and does not ever have a notochord. Porifera, cnidarian, Platyhelminthes, nematodes, and annelids all lack notochords
What are the products of the light-dependent reactions in photosynthesis?
O2, NADPH, and ATP The light-dependent reactions of photosynthesis occur in the thylakoid membranes of chloroplast. Here, cyclic photophosphorylation produces ATP through an electron transport chain, and noncylic photophosphorylation produces NADPH. Water is split during these reactions, releasing O2. These products, along with CO2 and rubisco, will become the reactants in the light-independent reactions of photosynthesis, which will produce C6H12O6, NADP+, and ADP.
Cooperativity
Occurs when O2 binds to hemoglobin, we see an increased affinity for O2 binding in the remaining subunits
absorption in kidney
Of the choices given, only glucose is both completely filtered and completely re- absorbed. Na+, urea, and K+ (choices B, C, and E) are completely filtered but not completely reabsorbed, and water (choice A) is neither completely filtered nor com- pletely reabsorbed.
some diseases
PKU: high amounts of amino acid phenylalanine. lack an enzyme needed for its metabolism gout: uric acid crystals deposit in tissues like the big toe diabetes insipidus: insufficient vasopressin production Tay sachs: lysosomal defect Hashimoto disease: thyroid involvement
about peripheral and integral proteins
Peripheral proteins are bound to the charged polar head group of the bilayer. Mild treatment with salts for ex can remove them. It is more difficult to remove the integral protein. Detergents, organic solvents, and ultrasonic vibrations are needed for their removal. Hydrogen bonding and electrostatic interactions allow peripheral proteins to be associated with the membrane. Integral proteins are held in the membrane by hydrophobic interactions with the lipid
What serves as a rapidly available reserve of high energy phosphates in skeletal muscle?
Phosphocreatine (or creatine phosphate) provides a quick energy source for skeletal muscles to contract when they need an initial energy burst
photoautotrophs
Photoautotrophs use energy from the sun to carry out photosynthesis: CO2 is also used. Red and blue light is most effective in promoting photosynthesis; Green is least effective Green light is reflected by plants, not absorbed About 3.5 billion years ago photoautotrophs appeared Cyanobacteria can carry out photosynthesis to produce O2 gas. It is thought that these bacteria played a major role in converting a reducing atmosphere devoid of O2 into an oxidizing atmosphere. This dramatically changed the life form composition on our planet
Nitrogen fixation
Plants require N2 to grow. Atmospheric N2 is converted into NH4+ or NO3- to be utilized by plants. Nitrogen fixing bacteria are located in root swelling called nodules. Plants that contribute to nitrogen fixation include the legume family. ex: peas, peanuts, soybeans and beans In nitrogen fixation, N2 from the atmosphere is converted to NH3
Plasmids
Plasmids are extrachromosomal genetic elements found in yeasts and bacteria The plasmid is circular and is sometimes called "vector DNA" which is double stranded Some plasmids can become part of the main chromosomes and is called an episome Plasmids can be transferred from one cell to another by viruses
Shrinkage of a cell due to water loss
Plasmolysis
About blood cells
Pluripotent stem cells arise in the early embryo and give rise to erythrocytes, platelets, and potential line of white blood cells. A blood clot (thrombus) may cause a heart attack or stroke. The kidney can produce erythropoietin in the tissues that are not receiving enough oxygen: red blood cell production in bone marrow is stimulated. Erythrocytes are most abundant. Leukocytes are least abundant. During an injury, the release of histamine will cause vasodilation and will allow white blood cells to squeeze out of the capillaries. A myeloma cell is a cancer cell with the ability for indefinite growth. If a lymphocyte is fused with a modified myeloma cell, a hybridoma cell results. These hybridoma cells can then produce a desired antibody
Which of the following best describes the enzyme that catalyzes the conversion of glucose into glucose-6- phosphate?
Polypeptide chain Enzymes are globular proteins, made of many amino acids bound to each other through peptide bonds (C is correct and E is wrong). Carbohydrates can be asso - ciated with enzymes but are not enzymes themselves (A is wrong). Lipids form membranes (B is wrong), and nucleic acids are DNA and RNA (D is wrong)
About Thyroid gland
Produces calcitonin (lowers calcium levels in the blood) and iodine-containing hormones thyroxine and triiodothyronine. they influence growth, development and metabolic rates. Ingestion of radioactive I-131 is a method employed to determine thyroid activity.
About Hormones
Prostaglandins are modified fatty acids that help induce fever, pain, sensation, and inflammation. Aspirin may inhibit prostaglandin activity. The pancreas has the dual function. It is both an exocrine and endocrine gland. Exocrine tissue produces lipase, amylases, and proteases and exports them to the small intestine via pancreatic duct. Endocrine function is to produce hormones like insulin and glucagon. Norepinephrine may act with epinephrine to increase glycogen breakdown and allow glucose release into the bloodstream. Norepinephrine can also act as a nuerotransmitter. The adrenal glands make hormones like epinephrine, norepinephrine, cortisol, and aldosterone. Ecdysone is a hormone that is involved in insect molting and metamorphosis.
about veins
Pulmonary vein and umbilical vein, unlike other veins carry oxygenated blood. Blood can bypass the liver due to the ductus venous. Most blood in the right atria is partly oxygenated and can bypass the pulmonary circulation by entering the left atria directly from the right atria by the foramen ovale. this shunt will divert blood away from the pulmonary arteries. the ductus arterioles conducts some blood from the pulmonary artery to the aorta thus bypassing the lungs
matching
Reptiles include lizards, snakes, turtles, and crocodilians. Fossil and other evidence show that reptiles evolved from amphibians. Reptiles have internal fertilization while amphibians have external fertilization. Crocodiles have a 4 chambered heart, but other reptiles have 3. fish -> amphibians -> birds = evolutionary relationship
ruminates
Ruminants like cows, sheep, and deer have a stomach with an alkaline pH The stomach has 4 chambers capable of digesting cellulose. The digestive tract of the animals harbors microorganisms (bacteria and protozoa) that can break the cellulose down into glucose The glucose molecules can now be absorbed and utilized for energy or storage Humans do not contain the microbes or the cellulose digesting enzymes of the ruminants
Freshwater and Saltwater fish
SUMMARY Fish in freshwater environments: Are hyperosmotic relative to their environment Drink very little water Salt enters the gills via active transport Produce large volume of urine In contrast, fish in saltwater environments (i.e. marine fish): Are hypoosmotic relative to their environment Constantly drink Salt leaves the gills via active transport Produce low volume of urine
Amylase is secreted by
Salivary and pancreatic amylase break down carbohydrates Pancreas also makes proteases and lipases
some facts
Sarcoma is only in connective tissue Carcinoma is only in epithelial tissue Satellite DNA is found concentrated at centromeres and at the ends of chromosomes Nucleic acids: DNA and RNA do not contain sulfur so to study nucleic acid metabolism, a researcher would have to use radioisotope 32-P
Sperm production
Semen contains sperm cells plus glandular secretions from the prostate gland and seminal vesicles. The Vas Deferens transports the sperm to the urethra then out the penis. The Cowper's (bulbourethral) glands add more thick mucous material to the sperm. Spermatozoa are matured in the coiled tube called the Epididymis. Sperm production (spermatogenesis) occurs in the seminiferous tubules of the testes. Leydig cells secrete testosterone that allows germ cells to mature into sperm cells
A scientist wishes to create bacterial colonies on an agar plate for observation of growth. Unfortunately, directly adding bacteria from the original culture results in too many bacterial colonies to count. In order to create a solution of proper bacterial concentration for observation, the scientist performs a three-step 1:100 serial dilution of the original bacterial culture. What is the dilution factor of the final solution?
Since the scientist used a 1:100 dilution, this means with every dilution the concentration was multiplied by 10-2. In this problem, the scientist performed a three-step 1:100 dilution, meaning they diluted the original concentration first to 10-2, then to 10-4, and finally to 10-6. The question asks for the dilution factor, which is the final volume divided by the original volume (or the inverse of the concentration), so we flip 10-6 to 106 to get answer
About earthworms
Skin of an earthworm secretes mucus which keeps the skin moist. Moist skin is needed for the gas exchange since earthworms have no respiratory organs. Salt can destroy the sensitive skin of earthworm and cause death
What is the purpose of SDS (sodium dodecyl sulfate) in protein analysis
Sodium dodecyl sulfate is a very strong anionic detergent that is used in gel electrophoresis to separate proteins based on their electrophoretic mobility (a function of the length of a protein and its charge). SDS is used to denature and linearize proteins and to impart a negative charge to the proteins. You could deduce it would impart a negative charge and not a positive one because sulfate is very negative and anionic. With this method, only the protein's size and charge will be compared. Generally, all gel electrophoresis will denature a protein to compare its size. SDS (sodium dodecyl sulfate) has three primary effects on protein: Denatures the protein Linearizes the protein Adds negative charge to the protein
Which hormone will inhibit many functions of the gastrointestinal tract?
Somatostatin suppresses the release of gastrointestinal hormones like gastrin, secretin, and cholecystokinin. This suppression will decrease the rate of gastric emptying along with reducing blood flow within the intestine
prostate gland
Sperm is unable to survive in highly acidic enviornments. The prostatic fluid helps to neutralize the acidic vaginal secretions and enhance sperm ability to swim (The sperm is relatively immobile in the acidic contents of the epididymis) In addition, the seminal fluid is neutralized since it is too acidic due to metabolic waste produced by stored sperm cells
Diploid/haploid stages
Spermatogonium: diploid 1 spermatocyte : diploid spermatid : haploid , differentiate into mature sperm cells oogonium : diploid 2 oocyte: haploid
An increase in calcitonin would lead to which of the following?
Stimulate osteoblast activity Two hormones regulate calcium levels in blood: calcitonin (produced by the thyroid), and parathyroid hormone (produced by the parathyroid). Calcitonin serves to lower calcium levels in blood. It does this by stimulating osteoblast activity, which builds up bone, which requires using calcium in the blood. Parathyroid hormone is the opposite, if calcium levels are too low in the blood, it will stimulate osteoclast activity to release calcium from the bones to the blood.
Penicillins inhibit bacteria to
Synthesize its Cell Wall. Bacteria are constantly rebuilding cell walls to maintain structure and function
Layers of the skin
Tattoos are on the dermis of the skin. Stratum are part of the epidermis. The hypodermis is the subcutaneous tissue that is below the dermis and has larger blood vessels than the dermis.
fluid mosaic model
The bilayer is not symmetric. The inner and outer faces are not the same. Lipids and proteins are capable of lateral movement but the movement of either from one face of the bilayer to the other is prohibited. The fluid mosaic model is the most widely accepted description of the cell membrane. In this model, proteins can float within the lipid bilayer while traversing the plane of the membrane
During embryonic development, a hollow sphere of cells is called a: A. blastula. B. morula. C. chorion. D. yolk sac. E. gastrula.
The blastula is the stage of embryonic development where liquid fills the inside of a morula to push the cells outward, forming a hollow sphere of cells. A morula is a solid ball of cells formed after cleavage. A gastrula is a 3-layered blastula (3 layers for the ectoderm, mesoderm, and endoderm), and is formed when a group of cells invaginate into the blastula. The chorion fuses with maternal tissue to form the placenta. The yolk sac is empty in placental mammals, but it is used to give nutrients to the embryo in birds and reptiles. A. blastula A blastula is a hollow sphere of cells that forms during the process of blastulation, making this answer correct. The blastula forms after the morula and will eventually give rise to the gastrula. The outer layer of cells is called the blastoderm and the inner layer is referred to as the blastocoel. B. morula A morula is one of the first stages of development after zygote formation. A morula is a solid ball of cells that later develops into the blastula during blastulation. Due to its solid nature, this answer is incorrect. C. chorion The chorion is the membrane that develops around the embryo and regulates nutrient offspring from mother to offspring. It is formed by two distinct cell layers during development: the outer layer, formed by trophoblasts, and an inner layer, formed by the mesoderm. Since the chorion is not a stage of early embryonic development, this answer is incorrect. D. yolk sac The yolk sac is not a stage of the early developing embryo in mammals; instead it is a vascularized structure that provides blood supply to the developing embryo during the early stages of Like the chorion, the yolk sac is not a stage of early embryonic development (it is formed by the hypoblast), so this answer is incorrect. E. gastrula The gastrula is the structure that forms after the blastula has reorganized into a trilaminar structure (three layers). The three layers are the endoderm, mesoderm, and ectoderm. This answer is incorrect because the hollow blastula is replaced by the trilayered structure of the gastrula, which is not hollow.
During the mammalian fertilization process, what component of the oocyte is responsible for the binding of the sperm?
The correct answer is [C]. Vitelline is a similar component in the egg cells of sea urchins, and is responsible for much of the same function. Progesterone plays a role in leading the sperm to the egg, but not in the binding. The zona pellucida is the outer layer of the egg that is responsible for the initial binding of the sperm to the egg. The ZP3 protein is responsible for the species-specific binding of the sperm to the egg, but is more important for helping galactosyltransferase (GaIT) activate the acrosome reaction. Without it, the sperm will not be able to bind to the egg. Once the egg has undergone the acrosome reaction and fused with the sperm, it can then bind to the uterine wall. A. Vitelline membrane Choosing the vitelline membrane is at first a tempting answer, as it is an oocyte component that functions in the binding of sperm. However, the vitelline membrane (or vitelline layer) is the term used to describe this structure in non-mammals (for example, a common model used to describe the process of egg fertilization is the sea urchin - the sea urchin egg would be said to have a surrounding vitelline membrane); therefore the answer choice is incorrect. B. Centriole Centrioles are not a component of oocytes that function in the binding of sperm; therefore the answer choice is incorrect. A pair of centrioles make up a centrosome, found in the nucleus of animal cells which serve as microtubule organizing centers during cell division. C. Zona pellucida The zona pellucida (specifically the ZP3 protein) is the component of the oocyte responsible for the binding of sperm in mammalian fertilization, so the answer choice is correct. The zona pellucida is a glycoprotein membrane that surrounds the oocyte. It binds sperm, and is required to initiate the acrosome reaction (the sperm releases the contents of its acrosome as it approaches the egg which contributes to charge-based fast block of polyspermy). Other zona glycoproteins include ZP2, which helps in oocyte-sperm recognition and in the prevention of polyspermy, and ZP1, which cross-links ZP3 and ZP2. Without ZP1, the zona pellucida cannot form. D. Progesterone Progesterone is a gonadal steroid hormone, not a component of the oocyte; therefore the answer choice is incorrect. It does not function in any way to bind sperm. Progesterone is produced by the ovaries (later in pregnancy, the placenta also produces progesterone) and functions in the menstrual cycle and the development and maintenance of the endometrial wall and fetus. Birth control pills frequently use high dosages of progesterone (or progesterone and estrogen together) to cause negative feedback that suppresses LH and FSH levels, which in turn prevents ovulation from occurring. E. The uterine wall The uterine wall is not a component of the oocyte, nor does it function in the binding of sperm; therefore the answer choice is incorrect. The oocyte is already fertilized by the time it makes contact with the uterine wall. In mammals, the blastocyst embeds into the uterine wall approximately 6 days into pregnancy.
about cytoskeleton
The cytoskeleton is made of microtubules, microfilaments, and intermediate filaments. Prokaryotes and eukaryotes contain a cytoskeleton. The cytoskeleton is actually a network of protein fibers that give shape to a cell, protects the cell by maintaining structural integrity and is involved in cellular movements such as contraction and gliding. Intermediate fibers are made of Keratin, microtubules are built by tubulin and microfilaments by actin. Both cilia and flagella are made from microtubules in a 9 + 2 pattern. Nine fused pairs of microtubules dorm a ring that surrounds two center microtubules
All of the following are statements that support the endosymbiotic theory EXCEPT one. Which one is the EXCEPTION? A. Mitochondria and chloroplasts reproduce by a process similar to binary fission. B. The thylakoid membranes of chloroplast resemble the photosynthetic membranes of cyanobacteria. C. The DNA of mitochondria and chloroplasts is circular and lacks proteins. D. Mitochondria and chloroplasts both produce energy. E. Mitochondria and chloroplasts have two membranes that consist of a lipid bilayer separated by an intermembrane space.
The endosymbiotic theory states that eukaryotic cells originated from a mutualistic relationship between two prokaryotes. Some evidence that points towards this includes: Mitochondria and chloroplasts both have their own DNA separate from the rest of the cell, and this DNA is circular and without any proteins, much like prokaryotes. Mitochondria and chloroplasts have different ribosomes that are more similar to prokaryotes than eukaryotes. Mitochondria and chloroplasts reproduce independently of the host cell by a process that is similar to binary fission, used by prokaryotes. Mitochondria and chloroplasts have a double membrane, which could have resulted from one prokaryote engulfing the other prokaryote in an endocytosis fashion, forming a vesicle. The thylakoid membranes of chloroplasts resemble the photosynthetic membranes of cyanobacteria, which are autotrophic bacteria. The fact that mitochondria and chloroplasts produce energy is irrelevant.
What is the original source of energy used to drive the light independent reactions of photosynthesis?
The energy used to drive photosynthesis comes from light, or photons, choice [E]. The light independent reactions (Dark reactions, also known as the Calvin-Benson Cycle) takes the energy produced in the light dependent reactions along with CO2 to produce glucose. Substrate level phosphorylation is related to glycolysis, or breaking down glucose, so [A] is out. The idea of photosynthesis is to produce glucose, not to breakdown glucose, so [B] is out. Choice [C] is a plausible distractor, but ultimately the energy used in the photolysis of water comes from light as well!
What is the function of the epiglottis?
The epiglottis is a structure in the throat that prevents food from going down the trachea instead of your esophagus. If you've ever choked on food, it's probably because your epiglottis didn't do its job. The lower esophageal sphincter is a valve between the esophagus and stomach that controls the entry of food into the stomach and protects against reflux.
About Pregnancy
The first trimester is the main period in which organs develop. Because of rapid organ development the embryo is most sensitive to drugs and radiation which can cause birth defects. The embryo is called a fetus at about 8 weeks. During that second trimester, the fetus is very active and the uterus will grow enough for pregnancy to be noticeable. The final growth of about 1.6 feet and 7lbs occur during third trimester
What are concentric rings of bone matrix found in compact and cancellous (spongy) bone called
The lamella is bony concentric layers that surround a Haversian canal in bone. Tiny canal in bone is a canaliculi. Lacunae are the small spaces between the lamellae that contain bone called osteocytes. The canaliculi will provide a route by which nutrients can reach the bone cells and waste products removed. Lamellae rings are very strong and are formed from calcium, phosphate, and collagen. Periosteum is a membrane that covers the outer surface of all bones. It allows for muscle tissue attachments to the bone as well as assisting the passage of blood into and out of all bones.
About the Lungs
The left lung has 2 lobes, the right lung has 3 lobes. The right lung is larger than the left lung. Left lung is smaller than right lung and has a cardiac notch to allow room for heart and its vasculature
About female reproductive cycle
The menstrual cycle is 3 phases: menstrual flow, proliferative phase, and secretory phase. Menstruation will begin with the disintegration of the endometrium(inner lining of the uterus). The endometrium thickens in response to estrogen levels during the proliferative phase and vascularization occurs. During the secretory phase, the endometrium continues to thicken, arteries enlarge and glands grow in response to progesterone and estrogens. If pregnancy does occur, estrogens and progesterone levels remain high to prevent disintegration of the endometrium
About sickle cell anemia
The mutation occurs on the beta chain: glutamic acid residue is replaced by a valine. Electrophoresis gel pattern would be different between HbA and HbS. HbA is more negative than HbS since it contains glutamic acid. Patients with sickle cell are homozygous for sickle gene while patients with sickle cell trait are heterozygous so they have both kinds of hemoglobin. Sickle cell causes pain, cell fragility, and organ failure. In sickle cell trait (heterozygous) allele confers malaria resistance
Notochord
The notochord is the feature that will eventually develop into a part of the spinal discs. The spinal cord begins as the dorsal neural tube. Pharyngeal slits are present in all chordates at some point during their development. For fish they will become gills, in other animals it will evolve into the pharynx, and in urochordates they are part of the filter-feeding system. The muscular tail that extends behind the anus is known at the post-anal tail. The endostyle is what produces mucus for filter feeders. Because it also stores iodine, it is believed to be the pre-cursor for the thyroid gland. Chordates share four main features during their development that are important to know: Notochord Dorsal hollow nerve cord Pharyngeal gill slits Muscular post-anal tail
inspiration
The phrenic nerves cause the muscle fibers in the diaphragm to contract and move downward The size of the thoracic cavity increases, but as volume increases the internal pressure decreases Atmospheric pressure forces air into the respiratory tract through the air passages as the lungs become inflated
A bacterial cell has its cell wall removed and is placed in distilled water. Which of the following will happen?
The rigid cell wall of bacteria is designed to protect it from changing osmolarities in the environment. Underneath the cell wall is a permeable plasma membrane. Placing the cell in distilled water will cause water to rush in, ultimately lysing the cell. This is because the cell has a higher osmolarity than the surrounding water, making it hyperosmotic to the water. Water will diffuse from areas of high concentration to areas of low concentration. The higher the osmolarity, the lower the concentration of water. This is similar to freshwater fish in a lake - water constantly enters the fish because they have a higher osmolarity. Hypertonic: more concentrated Hypotonic: less concentrated
muscle contractions
The sarcomere is the basic unit of skeletal (striated) muscle. The sarcomere is actually the repeating unit of myofilaments that are found along the length of a myofibril. The myofibril is composed of actin and myosin filaments. This distance between 2 Z lines will define a sarcomere. During muscle contraction, the I band and H zone shortens, while the A band stays the same.
Which layer of the skin helps the body conserve heat and protects the body from injury by acting as a "shock absorber"?
The subcutaneous layer contains a network of fat cells and collagen. It is the deepest layer of skin and the fat cells help insulate the body and act as a shock absorber to protect it from minor damage. The top layer of skin is the epidermis, which usually contains dead skin cells and contains melanocytes (produce melanin). The dermis is the middle layer and is highly vascularized. The dermis contains blood vessels, hair follicles, sweat glands, and nerves. A. Epidermis The epidermis is the outermost layer of the skin. The primary function of the epidermis is to serve as a barrier against pathogens and environmental dangers. Since the epidermis is not composed of fatty adipose tissue, and is mostly used for fighting off infections, this answer is incorrect. B. Dermis The dermis is primarily composed of flexible connective tissue. The dermis has many functions and is where sensory cells are anchored. The dermis is also responsible for supplying nutrients to the The highly vascularized and flexible dermis is adapted for sensation and nutrient recycling, not insulation or shock absorption, making this answer incorrect. C. Endodermis The endodermis is not a layer of human skin; instead it is found in vascular land plants, making this answer incorrect. The endodermis regulates the flow of water and nutrients through the symblast pathway. This is possible due to the hydrophobic properties of the Casparian Strip located in the endodermis. D. Subcutaneous layer The subcutaneous layer, part of the hypodermis, has a number of functions, including insulation and shock absorption, making this answer correct. The fatty, adipose tissue that makes up the subcutaneous layer of the skin is what helps it have functions such as shock absorption, insulation, and (in some species) energy storage. E. Mesoderm The mesoderm is not actually a layer of the skin; instead, it is one of the three germ cell layers formed by gastrulation in developmental biology. The mesoderm gives rise to a number of different tissue and cell types, including muscle tissue, mesenchyme, mesothelial tissue, and some blood cells. Since the mesoderm is not a part of the skin, the answer is incorrect.
About Altitude zones
There are 4 zones: (low elevation)Lowlands, Montane, subalpine, and alphine (high elevation). Zones depend on factors like soil composition, elevation, humidity, and temperature. Montane zone forests include fir, spruce, and pine trees. As you move higher, temps and species number decrease. Once the alpine zone is reached, there is a big vegetation change. No trees only shrubs and herbs.
All of the following are connective tissues EXCEPT for one. Which one is the EXCEPTION? A. Adipose B. Neurons C. Cartilage D. Bones E. Blood
There are four general classes of biological tissues: connective, epithelial, muscular, and nervous. Neurons, although connected, are not a connective tissue in the musculoskeletal system. Adipose, or body fat, is a connective tissue. Cartilage connects bones to other bones. Bones are a connective tissue as well. Blood, interestingly enough, is considered a connective tissue. Blood is derived from the mesoderm and connects the body systems together by providing nutrients and removing waste.
Which of the following components of the immune system responds to specific antigens? A. B cells B. Interferons C. Phagocytes D. Cilia E. Lysozyme
There are two parts to the immune system: specific and nonspecific defense. Specific defense responds to antigens, such as the toxin from an insect sting, or a molecule on the plasma membrane of a pathogen. Nonspecific defense is not specialized for a particular pathogen; it defends against all pathogens in general. Examples of nonspecific defenses include: skin, interferons, phagocytes, cilia, and lysozyme. Interferons are molecules secreted by cells invaded by viruses that stimulate other cells to help defend against viruses. Phagocytes are white blood cells that engulf pathogens. Cilia line the lungs and help sweep pathogens out of the lungs. Lysozyme is a protein that breaks down cell walls in bacteria.
Why have phosphates been restricted from use in pesticides and detergents
They cause the growth of plants and microorganisms. Phosphates are nutrients for plants and microorganisms. Excess could decrease supply of dissolved O2 = eutrophication
hormones
Tropic hormones have another endocrine gland as a target -most tropic hormones are produced and secreted by the anterior pituitary gland -tropic hormones include LH, FSH, TSH, and ACTH TSH: stimulates the thyroid gland to make and release thyroid hormone LH: stimulates the ovary and testes FSH: stimulates eggs maturation and sperm production ACTH: stimulates the adrenal cortex to release glucocorticoids such as cortisol
After drinking, what causes an increase in urine production
Vasopressin or antidiuretic hormone is involved in the body's ability to retain water and thus reduce urine output. Vasopressin can also raise blood pressure due to vasoconstriction. Alcohol will block the creation of vasopressin, thus the urge t urinate occurs. This peptide hormone is made in the hypothalamus and stored and released by the posterior pituitary gland
Microvilli and Villi in small intestine are associated with what
Villi contain capillaries and laterals and are covered with microscopic "hairs" called microvilli that further increase surface area and aid in food absorption
plant like protist
Volvox Paramecium is a unicelled protozoa, mold is a fungi that can release tiny spores into the air Amoeba is a single celled protist that moves by pseudopodia Dandelion is a producer, a flowering plant
Convergent Evolution
When 2 species with the same characteristics came from different ancestors
Noncompetitive Inhibition
When an inhibitor binds to the enzyme at a binding site other than the active site and prevents the enzyme from catalyzing the reaction, it is noncompetitive inhibition
What is the most accurate way to work out molecular structures
X-ray diffraction
Plants
Xylem contains 2 types of cells: tracheas and vessel members Xylem conducts water and dissolved mineral absorbed from the soil, and mechanically supports the plant. The yearly xylem deposits make up the annual growth rings used to record the age of a plant Phloem is another vascular tissue consisting of sieve tubes through which sugars and other solutes are conducted
Fungi groups
Zygomycetes Basidiomycetes Lichen Ascomycetes Lichen is a combination of blue green algae with a fungus. ex: of symbiosis. Alga supplies food while the fungus protects the alga and absorbs water and minerals for both
Killer T-cells
a cytotoxic cell (killer Tcell) will kill the bodys own cells that have been invaded by a bacteria or virus and kill cancer cells This cell will bind to an antigen-infected cell, release perform and will cause the plasma membrane to become perforated Helper Tcells are the specific target for the virus that causes AIDS (HIV) They develop in the thymus glands and do not release antibodies USe protein perforin to lyse their targets
what is a monotreme
a mammal that can lay eggs ex: platypuses and echidnas Kangaroo= marsupial: mammal that completes embryonic development in a pouch
adaptive radiation
a number of different species emerge from a single ancestor
Palindrome DNA sequences that could be a potential enzyme site
a palindrome is read the same from left to right as it is from right to left ex: GGATCC
biomes
a savanna is a tropical grassland that may cover tropical and subtropical areas like parts of Australia and Africa Ungulates are giraffes: seen in African Savanna Grasslands and savannas my receive an average of 25 inches of rainfall a year to prevent the regions from turning into deserts Seasonal drought, fires, and large mammals grazing may be seen in the grasslands Grasslands soils are among the most fertile in the world
rise in which ion triggers the cortical reaction and incites metabolic changes within an egg cell
a wave of Ca2+ is released from the endoplasmic reticulum and acts as a second messenger. the cortical reaction helps prevent polyspermy. a high concentration of Ca2+ is vital for the cortical reaction to occur. These Ca2+ ions are involved with allowing cortical granules to fuse with the plasma membrane
What is in between heart muscle cells
adjacent cells are held together in cardiac muscle by intercalates disks. These disks have a very low resistance to the passage of impulses to allow the cardiac muscle fibers to transmit electrical impulses rapidly
recessive v dominant in pedigrees
affected male passes onto both daughter and son = autosomal does not skip a generation = dominant skip a generation = recessive
after exposure to HIV
after exposure to HIV, the body develops antibodies to set up an attack against invading virus. This process is called seroconversion. During seroconversion, HIV antibodies might not be detectable and thus lead to a false negative. Seroconversion generally takes place within a few weeks of initial infection and often is accompanied by flulike symptoms, rash, swollen glands, and fever
surfactants
alveoli has surfactants that reduce the surface tension of the fluid within an infants lungs so that breaths are not laborfull Once alveoli expand, they tend to stay expanded and not collapse under surface tension after each breath The first breath must be particularly forceful since the newborn's lungs are collapsed and the airways are small. Therefore, collapsed lungs, surface tension, and small airways offer resistance to air movement Stimulation of the first breath is initiated by high CO2 levels
what allowed amphibians to successfully invade land
amphibians do not completely live on dry land since their reproduction depends on water Amphibians were successful due to development of lungs, legs, redesigned heart and the ability to develop a means to prevent drying of the skin Amphibians do not have an amnion amphibians developed from air breathing lobe fin fishes
In what phase does cytokinesis begin
anaphase
what is the reproductive structure of angiosperms
angiosperms are flowering plants that are divided into monocots and dicots. The flower is the reproductive structure of an angiosperm
matching
aorta: vessel with the highest blood pressure ; largest artery in the body -Bradycardia: slow heart rate Tachycardia: fast heartbeat coronary artery : aortic branch that supplies blood to the heart -blood pressure is measured by a sphygmomanometer -a manometer measures gas pressure
Arteries
arteries carry high pressure from the heart to arterioles arteries have the strongest and thickest walls comprised of 3 layers (tunics): endothelial lining, middle layer of smooth muscle and elastic tissue and an outer layer of connective tissue
relations
as predator populations increase we see a decrease in prey population as prey decline we see a decline in predators parasites and hosts increase or decrease together
about Tay sachs
autosomal recessive disease in which a lysosomal enzyme defect occurs and causes lipid buildup in brain cells fatal disease
about bones
axial skeleton includes skull, vertebra, and ribs. The appendicular skeleton includes the bones of the arms and legs as well as the bones of the pelvic and pectoral girdle. Ligaments connect bone to bone while tendons connect bone to muscle. at the end of long bones, are regions of cartilaginous cells where growth occurs this is called the epiphyseal plate. compact bone contains structural units called Haversian systems. blood vessels are nerves pass through the Haversian canals
Classification for fungi
based on type of sexual spores produced
common bile duct carries bile from the gall bladder and conducts it into the
bile is brought to the duodenum (first part of small intestine) by the common bile duct. Bile contains bile salts, bile pigments, water and various electrolytes in addition to cholesterol
how does novocain, a local anesthetic prevent action potentials from occurring
blockage of Na+ voltage gated channels
Blood brain barrier
blocks cells that prevent or slow the passage of drugs, ions, and pathogens into the central nervous system Barrier is permeable to O2, CO2, glucose and anesthetics
about osteoporosis
bone becomes fragile and more likely to fracture estrogen can help maintain bone density prevention includes calcium and vitamin D bone density decreases
Brain sections
brain is divided into 3 sections: forebrain(prosencephalon), midbrain(mesencephalon), and hindbrain(rhombencephalon, Upper telencephalon (containing cerebrum) and lower dicephalon (containing thalamus and hypothalamus) make prosencephalon medulla and cerebellum are components of the rhombencephalon
RBC in distilled water will
burst, swell Urine is hypertonic to the blood and contains high urea and solute concentration
main form of the calcium in bone
calcium phosphate most calcium is in bone and teeth
rain shadow
can be seen in deserts it is a reduction in rainfall on the leeward side of a high mountain causes no moisture The leeward side is that side not facing the wind
traits of mammals
can produce milk, have 3 bones in the middle ear, have hair or fur, have heterodont dentition (different kinds of teeth), have sebaceous (oil producing) and sudorifeous (sweat) glands -Poikioltherm is an organism that has varied internal temperature such as amphibians, reptiles and some invertebrates
carbon cycle
carbon moves from reservoirs in the atmosphere and oceans, through organisms then back to reservoirs Carbon enters the atmosphere by way of aerobic respiration, the burning of fossil fuels and volcanic eruption which release carbon from rocks deep in the Earth's crust In aquatic food webs, carbon can be integrated into shells and other parts The burning of fossil fuels is one of the biggest environmental problems. However, the ocean does absorb some of the CO2 being added Bacteria and fungi cleave carbon compounds in the bodies of dead plants and animals and convert them to CO2. Over a long period of time, the bodies of many of them may form petroleum
number of gametes
count number of heterozygous gametes: n then do n^2
where do food and air passages cross
cross in pharynx region -gas exchange will occur in the alveoli by passive diffusion
where are melanocytes found: produce melanin
deepest layer of the epidermis is called stratum germinativum. This layer contains the melanocytes. Stratum corneum is the outmost layer containing the dead epithelial cells. The dermis is below the epidermis. The dermis consists of connective tissue, containing erector muscles, hair follicles, sensory recpetors, sweat and sebaceous glands
about birth control
designed to deceive the body into thinking that pregnancy has occurred. Estrogen and progesterone are used. Progesterone will decrease FSH and LH so pregnancy will not occur. In males, FSH maintains sperm production and LH stimulates Leydig cells to make testosterone. Male pill can interfere with LH and FSH to lower sperm production
each spinal nerve emerges from the cord by 2 branches that are contained within the vertebral column These branches are called the ventral root and the dorsal root Which root contains cell bodies of the sensory neurons
dorsal root is the sensory branch of the spinal nerve while the ventral root is the motor branch of a spinal nerve
Plants
during light reactions, a high H+ is produced within the thylakoids. the light requiring reaction of photosynthesis produce NADPH and build a high conc of H+ ions that are used to make ATP. ATP production does not need light. In dark reactions, that occur in the stroma of the chloroplasts, ATP and NADPH are used in the fixation of carbon. during this carbon fixation, CO2 is incorporated into the carbohydrate molecules. the calvin cycle (dark reactions) requires 2 ATP and 2 NADPH for each CO2 molecule incorporated into carbohydrate and the production of ribulose biphosphate requires 1 ATP, a total of 3 ATP and 2 NADPH are used for each CO@ molecule that becomes carbohydrate. O2 is a byproduct of the light reaction. the dark reaction can occur either with or without light as long as ATP and NADPH and H+ are present. PGAL is made during the dark reaction from CO2 and ribulose. six turns of the calvin cycle are needed to produce a glucose molecule
DNA Replication
during replication process, an OH group at C3 reacts with the 5 phosphate group of a growing polynucleotide chain If a group such as N3 is present, no nucleophilic attack can occur, so the polypeptide chain growth cannot occur
Allosteric interaction
during this, when a molecule binds, a conformational change occurs and the primary binding site will no longer bind to its unusual substrate. In the Bohr effect, we see hemoglobin unloading O2 under conditions of low pH (high CO2)
a restriction endonuclease recognizes a specific sequence and makes a cut within a DNA molecule. this specific sequence is called
each restriction endonuclease hydrolyzes a specific bond in DNA. this is called palindrome.
about food pyramid
each trophic level represents different quantities of potential (stored) energy, with the producers ex: plants have greatest. Energy and mass will decrease as you move up this food energy pyramid. on bottom: Producers (plants): most mass, energy, and number of individuals Herbivores (primary consumers) carnivores (secondary consumers) Top carnivores (tertiary consumers) on top
food
each villus of the small intestine contains a capillary network and a lacteal that absorbs nutrients. Nutrients are carried into the bloodstream. The nutrient rich blood is conveyed through the hepatic portal vein to the liver which will regulate the blood nutrient content. The hepatic portal vessel has first "access" to nutrients that have been consumed by a person after a meal. as glucose rich blood passes through the liver, excess glucose is removed and stored in the liver as glycogen. The liver will remove excess glucose and amino acids from the blood to prevent tissue damage. blood will leave the liver and be transported to the heart, which then pumps blood to the rest of the body (villi -> bloodstream -> liver -> heart -> body)
light reaction of photosynthesis
electron are transferred from water to NADP+ and ATP is produced during the light reaction of photosynthesis -ATP is produced -Water is oxidized -NADP+ is reduced 2NADP+ + ADP + Pi + 2H2O ---> O2 + 2NADPH + 2H+ + ATP
matching
ependymal cells are involved with production of cerebrospinal fluid Kupffer cells located in the liver are specialized macrophages Chondrocytes are involved with the forming of cartilage Renin is an enzyme that is produced by granular cells of the juxtaglomerular apparatus (tissue in kidney) that regulates arterial blood pressure Sertoli cells are found in the testes and are involved with nourishing the developing sperm
arthropods
example : crayfish: crustaceans sheds its exoskeleton in a process called molting arthropods have bilateral symmetry and an open circulatory system
Zigome activation
examples are trypsin and chymotrypsin Activation of their precursors (trypsinogen and chymotrypsinogen) occurs by cleavage of peptide bonds using enzymes
where does fertilization occur
fallopian tube (oviduct) fraternal twins develop from 2 eggs which were fertilized independently of each other head of a sperm consist largely of a nucleus blastula is a hollow ball of cells trophoblast consists of a double layer of cells and will be the precursor of the placenta
about mitochondrial matrix
fatty acid oxidation and Krebs cycle occur in this region. Acetyl CoA accumulates here since pyruvate decarboxylates to enter the Krebs cycle (TCA cycle) as Acetyl CoA
which lacks a dorsal hollow nerve cord? a. snake b. alligator c. human d. frog
feature of chordates. in chordates, nerve chord develops into brain and spinal chord. all are examples of chordates
cell involved in the synthesis of extracellular matrix and collagen
fibroblasts they are also the common type of cell found in connective tissue
matching
fish : 2 chambered tubular heart frog : 3 chambered heart Artery: no valves pulmonary vein : oxygenated blood ascending loop of henle : impermeable t water. as urine descends the loop of henle, it becomes more and more concentrated and becomes less concentrated in ascending branch
genomic library and cDNA
genomic library: contains all the sequences that are present in the chromosomes and even contain those DNA sequences not transcribed cDNA library: made as a DNA copy of mRNA and contains only the DNA sequences that are expressed in the cell
N2 is replenished into the atmosphere by:
gentrifying bacteria convert nitrates or nitrites to free N2. in order for this to occur, there must be insufficient O2 present causing bacteria to use NO3 - or NO2- instead of O2. Nitrifying bacteria convert N2 to nitrogen containing species needed by plants
in glomerular filtrate, what should be completely reabsorbed
glucose This reabsorption occurs in the proximal convoluted tubule In diabetes blood glucose levels rise high and significant quantities of glucose appear in urine
Info
goiter: improper thyroid function pancreas: exocrine and endocrine activity melatonin: pineal gland kidney: main target organ of ADH calmodulin: an intracellular protein that Ca2+ binds. Calcium-calmodulin complex is capable of triggering a cascade of protein activators. The contraction of smooth muscle involves activation utilizing the Ca2+
In the alternation of generations, what do spores directly give rise to?
haploid spores divide by mitosis to form the gametophyte stage. These gametes fuse together to form the diploid stage and develop into a sporophyte, which then divides by meiosis to get back to the haploid stage. A. Gametes Gametes are produced from mitosis via the gametophyte structure in alternation of generations; therefore the answer choice is incorrect. B. Zygotes Zygotes - the fusion of sperm and egg - are not produced from spores, but rather the fusion of gametes (which are produced by the gametophyte); therefore the answer choice is incorrect. C. Gametophyte In the alternation of generations, spores produced by the sporophyte go through mitosis and form the multicellular gametophyte structure, so the answer choice is correct. D. Sporophyte The sporophyte is the multicellular structure that produces spores via meiosis, but the question asks what spores give rise to - not where they come from - therefore the answer choice is incorrect. E. Seeds A seed consists of a protective coat, some kind of storage material (usually food), and the developing plant embryo (developed from the zygote). The seed allows for the eventual formation of the sporophyte, and does not develop from spores; therefore the answer choice is incorrect.
chlorophyl is similar in structure to:
heme group in myoglobin, hemoglobin, and cytochromes In chlorophyll, the metal is Mg rather than Fe
hormones
hormones are intracellular messengers produced by ductless glands Hormones include steroids like testosterone and progesterone as well as peptides like insulin Binding of hormones can cause a cascade to occur that can activate biochemical pathways Steroid receptors occur within the cell, for example, they may bind directly to the receptor in the nucleus Insulin, however, binds to its receptors that is on the outer face of the plasma membrane
which structure is considered the link between the nervous system and the endocrine system
hypothalamus is the link between the endocrine and nervous system. the hypothalamus helps regulate the heart, arterial blood pressure, produce neurosecretory substances, regulate H2O and electrolyte balance, body temperature, and maintain homeostasis
about internal and external fertilization
in external fertilization, eggs shed by the female are fertilized by the male in the environment. External fertilization is seen in most fish and amphibians. internal fertilization involves sperm being deposited into the female reproductive tract. Internal protects from predators whereas in external, predators reduce chance of survival into adulthood
unsaturated v saturated bonds
increase degree of unsaturation = more double bonds = increase in fluidity and decrease in melting point cis double bond puts a kink and prevents it from tightly packing into a crystal In warm enviorenemtn, organisms want to increase its % of saturated fatty acids to ensure that membrane does not get to fluid like increase the degree of saturation = increase melting point but decrease fluidity Prokaryotes lack cholesterol in their cell membrane unlike eukaryotes
according to the impact hypothesis, an asteroid or comet struck the earth and caused mass extinction. A thin layer of which element separated Mesozoic from Cenozoic sediments?
iridium
about lac operon
lac operon has 3 structural genes that allow for synthesis of 3 enzymes for lactose metabolism. Lactose binds to the repressor and inactivates it. Thus, the lacoperon can now produce mRNA for the enzymes needed. It is also required that glucose be absent. If glucose is absent, a positive gene regulation occurs. Cyclic AMP is able to activate CAP, a key protein that stimulates transcription by binding to the promoter site and helping RNA polymerase association. Thus +lactose and -glucose allow for transcription of the needed enzymes
Electrophoresis
largest towards the top (near the negative end) Smallest towards the bottom
steroid hormones
lipid soluble and can easily pass through cell membrane They are synthesized from cholesterol
serous membranes associated with the lungs are called:
lungs have a thin, smooth membranous outer covering called pleurae. Alveoli are the basic respiratory unit where actual gas exchange occurs by passive diffusion. A sinus is a cavity or hollow space in a bone.The peritoneum is the tissue that covers all the digestive organs and lines the body cavity. the fleshy, outer portion of the external ear is the pinna.
fraternal twins
made form 2 sperm and 2 eggs
Large Intestine
main function of large intestine (colon) is the reabsorption of water, sodium, and other minerals. The bacteria in the large intestine make Vitamin K. These bacteria are the chief source of vitamin K. Feces are stored briefly in the rectum and eliminated through the anus. The portal vein directs glucose and other monosaccharides to the liver. Thus, the large intestine functions in not only waste storage, but also water conversation and ion regulation
what has a 4 chambered heart
mammals and birds have 4 chambered hearts -fish have a 2 chambered heart -amphbians and reptiles have a 3 cham chambered heart
matching
mandible: strongest bone of the face Foramen magnum : spinal cord passage TMJ : lower and upper jaw attachment Foramen : passage of nerves
cells
memory cells: secondary immune response monoclonal antibodies: B-lymphocytes fused with myeloma cells; defensive proteins Antibodies: immunoglobulin proteins Active immunity: conferred by recovering from disease
Human oocytes can be fertilized most successfully by the use of which technique
microinjection involves directly injecting sperm cells into an egg In-vitro fertilization involves fertilization between an egg and a sperm in a glass dish in lab
about archaea
microorganisms that exist in extreme environments, but also found in most environments. no pathogenic archaea have been found. archaea are closely related to eukaryotes and lack peptidoglycan cell walls.
ATP synthase is associated with
mitochondia and chloroplasts
reactive sequence where acetyl coA can serve as the starting compound for the biosynthesis of carbohydrates
modification of citric acid cycle where sugars can be made from acetyl coa found in bacteria and plants called glyoxylate cycle
muscles
myosin = thick filament actin = thin filament A band = A band is the entire length of the thick filament, including where the thick filament overlaps the thin filament. I band = area with only thin actin filaments Z line = attached to the thin filaments sacromere = region between Z lines. H zone = only contains thick filaments
chemoautotrophs
need only CO2 as their carbon source. They will oxidize inorganic molecules such as NH3, H2S, elemental sulfur and even Fe3+.
features
nematodes have a complete digestive system -two pairs of antennae distinguish insects from crustaceans -hydras, jellyfish, and echinoderms display radial symmetry -crustaceans are the only arthropods with two pairs of antenna -Platyhelminthes have an incomplete digestive system; they have a single opening for substances to enter and leave the body Flatworms are bilaterally symmetrical and contain a centralized nervous system containing a brain and nerve cord
parthenogenesis
new individuals are produced without fertilization
acetyl CoA being converted to citrate
occurs in mitochondrial matrix, is the first step of the citric acid cycle. Acetyl CoA contains a thioester bond that when hydrolyzed releases energy. This "high energy" bond is the source of this exergonic reaction
genetics
pleiotropy: single gene that affects many traits in an organism Epistasis: phenomenon that occurs when one gene pair masks or modifies the expression of another gene pair
Animals whose body temps vary with the external environment are
poikilotherm
Pollen
pollen is a immature male gametophyte
Blue green algae
prokaryotes from kingdom monera. Also called cyanobacteria Reproduction is asexual by binary fission In lichen, cyanobacteria provide organic nutrients for the fungus, thus they live symbiotically (the fungus offers protection) together
movement
protists are eukaryotes that have flagella or cilia Euglena has a flagellum Paramecium has cilia Amoeba has pseudopodia
timeline
protobionts>prokaryotes>eukaryotes>amphibains>reptiles>primates
What are analogous structures
similar structure functions but Evolved independently and are made from different structures
Which is most involved in the slow block to polyspermy in sea urchins
sperm proof fertilization membrane is formed when the cortical granules in the egg fuse with the plasma membrane. As a result, enzymes are released, biochemical reactions harden the vitelline layer and allow no further sperm from entering. This cortical reaction is referred to as "slow block to polyspermy" The acrosomal reaction is the fast block in which an electrical response occurs to change the membrane potential to prevent polyspermy
sporangia
sporangia are the spore producing and spore containing reproductive structures of ferns , angiosperms, gymnosperms, algae , fungi and bryophytes new swimming spores are released from the sporangia
Animals
starfish from phylum Echinodermata display radial symmetry ex: splitting them lengthwise along any plane yields 2 equal halves Coelenterates like jellyfish, sea anemones, hydra are radially symmetrical, have a single opening; a mouth used for transport and digestive purposes. Coelenterates are carnivores; they have tentacles to capture prey. These tentacles contain stinging called nematocysts Duck billed platypus is a mammal but does not develop its young internally Cartilaginous fish include sharks Chordates have a notochord as well as paired gill slits during embryonic development
methanogens
strictly anaerobic convert H2 and CO2 to methane can be found in gut of ruminants
which structure contains the hydrolytic enzymes needed to breakdown the protective surface of an egg cell?
the acrosome is a membrane bound structure found at the anterior end of most sperm cells. The acrosome contains hyaluronidase which is a hydrolytic enzyme that causes the breakdown of the protective surfaces of the egg
2,4 DNP is an uncoupler. What effect does this have on the electron transport system
the transfer of electrons through the electron transport system leads to the protons being pumped from the matrix to the intermembrane space. an uncoupler allows electron transport to continue but ATP synthesis ceases. they prevent the generation of the H+ gradient. H+ ions are stolen away and never utilized by ATP synthase to make ATP uncoupler dissipates the proton gradients
transcription
transcription occurs at the rough ER in eukaryotes -smooth ER=lipid metabolism
About bone stress
upon bone stressing, bone forming cells called osteoblasts deposit collagen and release calcium phosphate to strengthen the bone. Mineral hydroxyapatite is produced.
where is urea made
urea is the major end product of nitrogen metabolism urea is formed in the liver and then transported to the kidneys for excretion
urine leaves the kidney via
urine leaves kidney by the way of the ureters. from the kidney, the ureters carry the urine to the urinary bladder. urine is stored here until voided through the single urethra
hyperbaric oxygen therapy
used to treat ailments like bone infections, gas gangrene, decompression sickness, ulcers, and carbon monoxide poisoning. Obligate anaerobic bacteria are poisoned by O2. O2 may destroy the bacterial enzyme which contains metals like Mo or W at their active sites. O2 can also destroy these organisms by the production of radicals, which damage the cell by reacting with the proteins and cell membrane lipids. aerobic organisms have enzymes to remove O2 species like catalases, peroxides, and superoxide dismutases, but these are often absent in obligate anaerobes
Birds
warm blooded and have a four chambered heart classified in class Aves Penguins and ostrich are birds that cannot fly Bird wings is a system of lightweight bones and feathers and is vital for flight
Coding region of Lac Operon
where structural genes are found : Lac Y, Lac Z, and Lac A
a fertilized egg is called a
zygote, it is diploid
ATP is converted to cyclic AMP. This is catalyzed by adenyl cyclase. This enzyme is inactive until which hormone binds ?
Epinephrine
classes
Gastropoda: largest molluscan class. includes slugs and snail. single shell is characteristic of the class class crustacean: includes crabs, shrimp, lobster, crayfish, and barnacles class Arachnida includes spiders, ticks, scorpions, and mites class Cephalopoda includes octopus and squid
Gastrulation of the blastula
Gastrulation occurs when a group of the blastula's cells begins to fold inward, resulting in: Formation of three germ layers (endoderm, mesoderm, ectoderm) Formation of the archenteron (a center cavity completely surrounded by endoderm cells that eventually gives rise to the gut) Formation of the blastopore, the opening into the archenteron that becomes the mouth in protostomes and anus in deuterostomes
Identical twins are possible due to what
Indeterminate cleavage of a zygote
ATP being transformed into ADP is what reaction
ATP + H2O --> ADP + H2PO4- Hydrolysis reaction
what is an antigen
Antibody generating foreign macromolecules. Includes bacteria, fungi, viruses, protozoa, and parasites like worms
The primitive gut is called the archenteron and is lined by endoderm. The opening of the archenteron in the gastrula that becomes the anus in deuterostomes and mouth in protostomes is known as
Blastopore
Plant classifications
Bryophytes: mosses, non vascular land plants -Angiosperms : flowing pants -Sporazoans: Plasmodium
pancreatic enzymes
Chymotrypsin and trypsin are enzymes made by the pancreas These enzymes are proteases; involved in protein digestion
microorganisms that allow for the conversion of fibrinogen to fibrin produce what enzyme
Coagulase is an enzyme produced by staphylococcus bacteria that allows blood to clot
about fertilization
Corpus lute breaks down into the corpus albicans if no fertilization occurs. LH stimulates the corpus luteum to produce progesterone and estrogen which allow for the blood vessels to grow and for the uterine lining to prepare for implantation of the egg which is to be fertilized. If LH was to decrease, as in the case of no fertilization, progesterone levels fall, which cause the uterine wall tissue to break down and menstruation begins
Which process makes the most ATP
Electron transport chain which is in the inner mitochondira
Haploid stage is dominant
Fungi
longest stage of cell cycle
G1 is the longest stage of the cell cycle Organelles like mitochondria are produced during this stage M is the shortest stage
plant hormones involved in root growth and stem elongation
Gibberellins and Auxins are in plant growth and stem growth Ethylene promotes fruit ripening, abscisic acid inhibits growth and cytokines are involved in stimulating cell division
about hormones
Hormones can be steroid or nonsteroid derived. Nonsteroid hormones are made from amino acids (water soluble) while steroid hormone (lipid soluble) are derived from cholesterol. Norepinephrine and epinephrine are hormones that are nonsteroidal
About Echinoderms
Invertebrates. Include starfish, sea urchins, and sea cucumbers. They lack segmentation and adults display radial symmetry
substrate concentration at which the reaction rate is half of its maximal value is called the :
Km
What causes yellow skin discoloration
Liver problems prevent the normal removal of bile pigments via the digestive tract. If bile pigments like bilirubin get into circulation then they cause skin discoloration
What refers to a space inside a tube
Lumen Rings of muscles in the wall of the esophagus, stomach, and other specialized regions are called sphincters. The submucosa is a connective tissue with blood and lymph vessels along with nerve plexuses.
Karyotype is a visual picture in which chromosomes are arranged in order from largest to smallest. At which stage are the chromosomes examined
Metaphase: when they are most condensed
Facts
Methylation inhibits nucleoside packing acetylation helps
Which technique allows researchers to examine genes in a particular cell type and determine if they are expressed
Microarray Technology
phylums
Nematoda: hookworms and pinworms Platyhelminths: tapeworms and flukes Annelida: leeches and earthworms Echinodermata: sea urchins and sea stars Mollusca : corals and sea anemones
Oligodendrocytes
Oligodendrocytes are responsible for laying down the myelin sheath surrounding neurons in the central nervous system,. Remember, the central nervous system includes the brain and the spinal cord. Schwann cells perform the same function in the peripheral nervous system (PNS). Myelination insulates the neurons (like the plastic around an electrical wire) and allows the neurons to transmit electrical impulses more quickly and efficiently. Without myelination, your neurons will not be able to properly communicate together, resulting in a variety of diseases, such as multiple sclerosis.
any gene that has the potential to induce cancerous transformation is called a
Oncogene
What are allium cells
Onion cells
matching classes
Osteichthyes: bony fish Agnatha: hagfish and lamprey. they lack bones, scales, and fish Chondrichthyes: skates and sharks Amphibia: toads and frogs aves: birds reptilia: lizards, turtles, and snakes
Microfilaments
Our muscles are made of long chains of cytoskeleton comprised of two filaments - actin and myosin. Of these, actin is a microfilament, while myosin is a motor protein. If actin degenerates, then our muscles would not contract
a scientist wants to quickly "clone" a piece of DNA in vitro. which technique would she likely employ.
PCR, can make unlimited copies of DNA
Some muscles
Papillae are rough projections on the lounge surface that provide friction for handling food and contain taste buds. Papillary muscles are cone shaped and located in the heart Photoreceptors of retina of the eye have rods and cones. Ciliary muscles of eye is involved with changing lens shape
Cri du Chat Syndrome (shortening of chromosome 5) is a syndrome due to what
Partial Monosomy is when part of one chromosome is lost. In partial trisomy, the addition of only a portion of another chromosome is seen.
Transportation
Passive diffusion is the passage of a solute across a membrane from high to a low concentration Active transport is the transport across a membrane aginst a concentration gradient from a low conc to a high conc Carrier molecules are needed for facilitated diffusion and active transport Ions diffuse across the membrane down their electrochemical gradients
what buffer system works in the intracellular fluids
Phosphate The pH of the extracellular fluid is maintained by the bicarbonate buffer
protists
Phytoplankton are floating autotrophs on the water surface. Protists are eukaryotic organisms and generally classified according to locomotion. Many red tides produce toxic chemicals that affect humans as well as marine life. Red tides are caused by dinoflagellates, not red algae . Diatoms are yellow or brown and are quite unique due to their glass shells
Which structure contains the female gamete in certain plants like bryophytes
Plants produce gametes in structures called gametangia. Eggs are found in the archegonia. Eggs are fertilized in this female gametangia. The male gametangia are located in the antheridia and represent the sperm-producing structures. Motile sperm swim from the antheridia to the archegonia for fertilization
Bacterial protein that cleaves DNA at a specific site
Restriction endonuclease DNA ligases repair discontinued DNA Dehydrogenases are involved in redox reactions
fungal pathogen involved in food spoilage
Rhizopus
About sponges and arthropods
Sponges use choanocytes for trapping food particles. Most sponges are hermaphrodites and are sessile animals. Arthropods evolved from annelids. Jointed appendages have allowed arthropods much of their success. Copuation, walking, feeding, and defense is due to jointed appendages. Arthropods do not have blood; blood is used to describe a fluid in a closed circulatory system. Arthropods have an open circulatory system using a hemolymph. Flame cells are involved with the removal of water in worms
about thylakoids
Stomata control gas exchange by opening and closing. The chloroplast contains an inner and an outer membrane. The inner membrane contains a fluid called stroma. A series of stacked disks are presnt. Each disk is called a thylakoid, which contains the photosynthetic pigemnt. Meristem is found in higher plants and represents undifferentiated cell types. The apical meristem contains cells that produce branches and flowers.
Stem cells
Stem cells in the bone produce lymphocytes by mitotic division. Immunity results from the production of antibodies which are proteins. The immune system has 2 parts; antibody mediated immunity, regulated by the production of B cell antibody production and cell mediated immunity, regulated by T cells (mature in thymus)
What biome is below the Tundra
Taiga
respiration
The Eustachian tube is a narrow passage leading from the pharynx to the cavity of the middle ear. Respiration is controlled by the medulla and pons. Tidal volume is air exchanged during normal breathing Negative pressure is what occurs during inspiration During inspiration the lungs volume will increase, resulting in a decrease in lung pressure compared to the atmospheric pressure (Boyles Law) The increase in volume is bought by the contraction of the diaphragm and the action of the intercostal muscles
Pancreatic beta cells secrete insulin into the body. Which organelle would you expect to be heavily expressed in beta cells?
The Golgi apparatus is a group of flattened sacs that coordinate with the endoplasmic reticulum. The Golgi specializes in modifying and packaging proteins for secretion. Cells that secrete hormones often have a high expression of Golgi complexes to aid in protein secretion.
Miller-Urey Experiment
The Miller-Urey experiment used ammonia, methane, water and hydrogen sealed in a sterile arrangement of tubes and flasks with connecting loops. One flask was half-filled with liquid water and the other with 2 electrodes (to simulate lighting in early earth). The flask with water was heated to simulate the temperature of early Earth, and sparks were fired from the electrodes to simulate lightning. After 2 weeks, they observed several organic compounds, amino acids (11 out of 20) and their base starting materials. However, no complete nucleic acids were observed.
about aerobic respiration
The electron transport chain pumps protons out of the mitochondrial matrix, thus creating a proton gradient -Molecular oxygen is the final electron acceptor -Each NADH yields approximately 3 ATP and each FADH2 yields about 2 ATP -O2 is needed for the electron transport system to operate -FADH2 and NADH will transfer the electrons, not the oxidized form FAD and NAD+
Extracellular buffer system
The main extracellular buffer is bicarbonate. This is how CO2 is transported throughout the body. The body uses pH sensors to determine how much we have to breathe. If we are exercising vigorously then our cells will produce large amounts of CO2, which will lower our extracellular pH (make it more acidic due to the CO2), which will make us breathe more to expel the excess CO2. Phosphate and other proteins are used as the main intracellular buffer inside cells.
The zona Fasciculata
The middle zone of the adrenal cortex and reduces the glucocorticoid cortisol. Innermost cortical layer = zona reticularis and produces androgens, the precursor to testosterone in humans The zona glomerulosa produces the mineralocorticoids like aldosterone
During which step of translation does translocation occur?
Translation is the process of a ribosome reading mRNA and synthesizing a protein. There are 3 steps in translation. The first is initiation, when the small ribosome unit attaches to the 5' end of mRNA, the first tRNA attaches, and the larger ribosome unit attaches to form the complete ribosomal complex. The second step is elongation, where the ribosome continues down the codons of mRNA and moves the tRNAs from the entry site to the bonding site, and from the bonding site to the exit site. This phenomenon is known as translocation and takes place during elongation. Termination occurs when a stop codon is reached and no amino acid is joined to the growing peptide. Choice [D], migration, is not a term used in translation. Choice [E], extension, is also not a term used in translation,
DNA segments the are moveable are
Transposable elements
genetics
Western blot: detects specific proteins in tissues Southern blot: detects DNA sequences in DNA samples Northern blot: detects RNA in a sample Fluorescence correlation spectroscopy: studies cell to cell communication
blood
-Blood clotting involves a series of chain reactions in which fibrinogen is converted into fibrin -Fibrin fibers form a mesh that traps red blood cells to becomes a solid barrier to blood loss -Unlike other blood cells, white blood cells can leave the blood vessels and circulate in the lymphatic system -Antibodies (immunoglobins) consist of two heavy chains linked to two light chains by disulfide bonds. The disulfide bond S-S is seen in many proteins such as antibodies, hair, and insulin. Disulfide bonds restrict the way the protein can fold. The disulfide is a covalent bond
facts
-Inactivation of Na+ channels is solely responsible for the absolute refractory period. Thi period is the time during which another stimulus will not lead to an AP. -After the absolute refractory period, we see Na+ channels start to recover from inactivation and respond again by generating action potentials if a stronger than normal stimulus is added. This is now called the relative refractory period. Absolute refractory period sets an upper limit to action potential frequency Nissil bodies are rough ER and are involved in neuron protein synthesis Microglia are "resident" macrophages of the CNS
about pH profile of an enzyme in the small intestine and about competitive inhibitors
-Intestinal enzymes work best at pH 8 -competitive inhibitors compete with the substrate for the active site but cannot be overcome by the additional substrate. However, Vmax is unchanged
some facts
-Stroke volume is the volume of blood that is discharged from the ventricles with each contraction. The volume that is discharged from the outer ventricle each minute is the cardiac output -cardiac output = stroke volume x heart rate -stroke volume = end diastolic volume - end systolic volume -as stroke volume or heart rate increase, cardiac output will also increase -arterioles offer greatest resistnace to blood flow int he circulation -mature red blood cells lack a nucleus -striated muslces like cardiac and skeletal are composed of sacromeres
some facts
-The tunicate (sea squirt) is a chordate, but also an invertebrate -Echinoderms do not have a notochord during any development stage -Malpighian tubules of insects form uric acid and discharge it into the gut -The functional unit of excretion in the earthworm is the nephridium -Echinoderms and chordate are deuterostomes. The mouth is formed after the anus from the blastopore. In all organisms, the blastopore will form the mouth first
some facts
-When an amino acid enters the cytoplasm from a t-RNA molecule, it first goes to the ribosome -embedded in the cell membrane are proteins called aquaporins that regulate the flow of water -it is believed that the RNA molecule have been the first carriers of genetic information -eukaryotes arose about 1.5 billion years ago while prokaryotes arose about 3.5 billion years ago -earth is about 4.5 million years old
random facts
-a function of skin is to help regulate body temperature by allowing blood flow through its outer layers -progesterone will inhibit Fsh release and thereby prevent ovulation -Fungi are involved decomposition -A gametophyte is a plant that produces gametes and is haploid, while a sporophyte is a diploid zygote -a glucose molecule is oxidized into pyruvate ( 2 moles of pyruvate) during glycolysis
action potentials
-a nerve impulse is an all or nothing event -as diameter of an axon increases, there is a decrease in electrical resistance along its length -as the diameter of a nerve fiber increases we decrease electrical resistance so speed increases Thick nerve fibers allow for fast impulses -as intensity increases the number of action potentials increase -as stimulus intensity increases, the amplitude of the action potential remains constant -action potentials move faster along fibers that are thick -as stimulus increases, speed is constant
about glycolysis
-a net gain of 2 ATP is seen when glucose forms lactate -glycolysis is anaerobic respiration and can supply energy even if no TCA cycle operates -In yeasts growing anaerobically, pyruvate is converted into ethanol -Gluconeogenesis occurs to produce glucose from non-carbohydrate precursors -in active muscle, there is a higher amount of lactate formation also produces NAD+, which is necessary for glycolysis to continue
All of the following mutations would result in a change in phenotype EXCEPT for one. Which one is the EXCEPTION? A. Frameshift mutation B. Silent mutation C. Nonsense mutation D. Missense mutation E. Inversion mutation
A silent mutation is one where the mutation does not cause a change in the amino acid sequence that is coded. This is because the genetic code is degenerate, meaning that multiple codons can code for a single amino acid. So if we change only one base pair, we may still code for the same amino acid and no change in the phenotype would occur. A nonsense mutation is when an effective codon is converted into a stop codon, which immediately truncates the protein at that location. This is a lethal mutation. A missense mutation occurs when one base is directly substituted for another, causing a change in that amino acid codon.
payer's patches are numerous areas of lymphoid tissue associated with the :
Aggregation of lymphoid tissue can be found in the ileum of the small intestine. Peyer's patches contain macrophages, B-lymphocytes, T-lymphocytes, and dendritic cells (antigen- presenting cells for the T-lymphocytes). Peyer's patches are considered the "immune sensors" of the intestine
mineralocorticoids
Aldosterone is a mineralocorticoid isolated from the adrenal cortex Mineralocorticoids are involved with water and salt balance. Aldosterone stimulates kidney cells to reabsorb sodium ions and water from the filtarte, thus we see a rise in blood volume and blood pressure
conditioning
Classical: learning procedure in which a biologically potent stimulus (e.g. food) is paired with a previously neutral stimulus (e.g. a bell). Operant: type of learning where behavior is controlled by consequences. Key concepts in operant conditioning are positive reinforcement, negative reinforcement, positive punishment and negative punishment.
Series of mitotic divisions that follow fertilization are called:
Cleavage
cyclic AMP
Cyclic AMP --> AMP is catalyzed by phosphodiesterase ATP --> cyclic AMP is catalyzed by adenylate cyclase and integral membrane proteins
Denaturation
Denaturation will disrupt the secondary, tertiary, and quaternary structure, it is endothermic and causes the disorder. Polar amino acids contain O and N while nonpolar amino acids contain mostly C and H Petroleum is a mixture of hydrocarbons such as alkanes, alkenes, alkynes, and aromatics Proteins are polymers of amino acids
Bacteria Shapes
Diplo-: pairs Strep-: chain Staph-: grape-like clusters -coccus: spherical -bacillus: rod-like Spirilla/spirochetes: spirals
Ectotherms v. Endotherms
Endotherms: organism that derives most or all of its body heat from its own metabolism ex: birds, mammals, and fish Ectotherms: warms its body mainly by heat absorption from the surroundings ex: invertebrates, amphibians, and reptiles
Loose connective tissue (areolar) surrounding muscle fibers and muscle groups is called
Fascia is a loose connective tissue that covers the surface of muscle Cartilage tissue is surrounded by a dense fibrous connective tissue called Perichondrium Ligaments connect bone to bone, while tendons connect muscle to bone and represent dense fibrous connective tissue
Which of the following stores the most amount of energy, gram for gram? A. Starch B. Glycogen C. Polypeptides D. Fats E. Glucose
Fats store the most amount of energy in the body. They store roughly double the amount of energy carbohydrates (starch, glycogen, cellulose) store, gram for gram. The reason our body prefers to burn glucose is because it is easier to use in respiration and it is more readily available.
products of glycolysis and krebs cycle
Glycolysis produces ATP, pyruvate, NADH, H+ Krebs cycle makes ATP, NADH, FADH2, CO2, Neither cycle makes NAD+ as a product NAD+ is an oxidizing agent that is needed for glycolysis and also it is directly involved in Krebs cycle
Phylums
Green algae = spirogyra Red Algae = Rhodophyta Bryophytes = Moss Nematoda = Roundworms Annelida = earthworm Platyhelmint = flatworms
About Plants
Gymnosperms include spruce, pine, and fir trees. Angiosperms include fruits, flowering plants, maple oaks, and grass. Angiosperms are divided into monocots and dicots. monocots generally have parallel veins, while dicots have leaves with netlike veins. Land plants exhibit an alternation of generations in which the gametophyte (haploid multi-celled stage) alternates with a diploid multi-celled stage the sporophyte
about AIDS
HIV belongs to a family of viruses that gain entry directly into a host cell where they can "hide out" for long periods of time, even decades. HIV targets CD4 T cells a type of T cell that is directly involved in initiating an immune response. If virus fails to take over the T cells completely, it will not be able to replicate. However, some integration still does cellular damage and causes an immune system depletion which leaves a person vulnerable to fatal opportunistic infections in the months or years to come.
according to the ? effect, deoxygenated hemoglobin has a greater affinity for CO2 than does oxyhemoglobin
Haldane
about hemoglobin
Hemoglobin contains more than one binding site. It is allosteric. It can bind O2, CO2, CO, and H+. A low pH causes Hb to unload O2 as does high CO2. Hb is a tetramer consisting of 2 alpha chains and 2 beta chains. The arrangement of the two alpha and 2 beta chains gives hemoglobin its quaternary structure. Hb binds CO much tighter than O2. The nonprotein portion (prosthetic group) is called heme Anoxia: absence or severe deficiency of oxygen reaching tissues Apnea: temporary absence of breathing Hypoxemia: deficiency in oxygenation of the blood Dyspnea: Difficulty in breathing Hypoxia: diminished availability of oxygen in tissues Anemia: deficiency of red blood cells or hemoglobin
about cephalopods
Highly active, have high O2 demand -Cephalopods have closed circulatory system, mollusks have open circulatory system
Which molecule exerts action by only interacting with cell surface receptors
Insulin Steroid hormones like estrogen, progesterone, and testosterone bind to nuclear receptors, not cell surface receptors.
insulin
Insulin is derived from preproinsulin and pro-insulin The precursor molecules undergo hydrolysis reactions that modify them into the active insulin Specific protease enzyme cleave two peptide bonds that allow the mature insulin to form Insulin is a hormone that promotes the entry of glucose and some amino acids into muscle and fat cells and it lowers the level of blood glucose Insulin acts by binding to receptors located in the plasma membrane of target cells
eras
Most recent = Cenzoic. Dinosaurs appeared during Mesozoic era. First land vertebrates, land plants, fish, many alga appeared in Paleozic era. Invertebrates, monera, fungi were in the Precambian (oldest) era Cenzoic > Mesozoic > Paleozoic > Precambrian
eyes
Optic disks lack any photoreceptors This area of the retina is also called the "blindspot". Fibers of the optic nerve emerge here from the eyeball. The ciliary muscle of the eye can change the shape of the lens of the eye. If ciliary muscles relax, the lens flattens and this allows the lens to focus on distant objects
what regulates the passage of food from the stomach to the dudenom of the small intestine
Pyloric sphincter is a powerful circular muscle that serves as a valve which prevents food regurgitation from the intestine back into the stomach
a bacteria that destroyed the antibiotic tetracycline was discovered. What most likely conferred this antibiotic resistance
R plasmids can carry genes for enzymes that can destroy antibiotics like tetracycline
initiation of the heart beat is largely controlled by:
SA node or pacemaker is a small tissue mass located at the entrance to the right atrium. This node delivers electrical impulses at regular intervals that allow the heart to beat. This electrical excitation causes the atria to contract, thus pushing blood into the ventricles
Parts of organs/limbs
Small Intestine: duodenum, jejunum, ileum Vertebral column: cervical, thoracic, lumbar, sacrum, coccyx Upper Limbs: humerus, radius, ulna, carpal, metacarpal Lower Limbs: femur, tibia, fibula, patella, tarsal, metatarsal
The cellular organelle that is primarily responsible for the synthesis of secretory proteins is the
The ribosome is the organelle that syn - thesizes protein, whether it be cytosolic protein or secretory protein. Do not be confused by choice A. Yes, the rough ER is involved in the handling of proteins des - tined for secretion, but it does not carry out the actual synthesis of these proteins. That job is carried out by ribosomes bound to the rough ER, so C is a better choice than A. Also, do not be confused by choice E. The Golgi apparatus stores and packages secreted proteins but does not synthesize them. The centriole (choice B) is involved in mitosis, and lysosomes (choice D) aid in cellular digestion.
about WBC
There are 2 branches of the immune system: humoral immunity and cell-mediated immunity. Humoral immunity acts against pathogens like free viruses and bacteria and is based on the circulation of antibodies. Cell-mediated immunity works against pathogens that have entered body cells by use of T cells
Cells
Totipotent cells can form all body cells including embryonic tissue Pluripotent cell can also create all cell types, except for extra-embryonic tissue like placenta
gastrula
U shaped hollow structure 14 days after fertilization the gastrula forms During gastrulation, the three primary germ layers are formed: ectoderm, mesoderm, and endoderm Once gastrulation is completed, evidence of cell differentiation can be observed
9:3:3:1 1:2:1
a. = found in F2 b. In F2 = bc of incomplete dominance
