MCAT BIO

Aldosterone

"salt-retaining hormone" which promotes the retention of Na+ by the kidneys. na+ retention promotes water retention, which promotes a higher blood volume and pressure

Erythrocyte

(RBC) ---Hormone erythropoietin in kidney stimulates bone marrow to make RBC ---NO NUCLEUS OR MITO OR OTHER ORGANELLES ------does require ATP, relies on glycolysis to make ATP ---After 120 days, degraded by phagocytes ---Carry O2 from lungs to tissues, CO2 from tissues to lungs ---Requires large surface to volume area to exchange gas ->flat and biconcave shape

Rhythmic Excitation of Heart (SA Node)

--Initiation of AP starts in sinoatrial node SA (in the upper part of the wall of the right atrium)->act like pacemaker of the heart --Divided into phase 4->0->3 --SA node has an unstable resting potential (phase 4 automatic slow depolarization) --caused by special Na leak channels ->brings cell potential to threshold of voltage gated Ca2+ channel ->open of Ca channel causes phase 0->Ca2+ drives the membrane potential of the SA nodal cells towards positive Ca2+ EQ POTENTIAL->Phase 3: repolarization caused by closure of Ca2+ channels and opening of K+ channels ->outward flow of K ->drives membrane potential back down toward negative K+ eq potential --SA node has the most Na+ leak channels so it reaches the threshold first set heart contraction rate

Mechanical stimuli: stretch of the lungs and irritants

->the stretch of the lung tissue stimulate stretch receptors that inhibit further excitatory signals from respiratory center to the muscles involved in inspiration ->inhibits inspiration ->irritation of inner lining of lung stimulates irritants receptors ->reflexive contraction of bronchial smooth muscle =bronchoconstriction -> prevent irritants enter the passageways -> determined by parasympathetic nerves that releases Ach. Histamine also causes bronchoconstriction. Epinephrine opposes this by bronchodilation.

Eq potential for Na+

+50mV

WEAKER the intermolecular force, HIGHER VP.

- Adding more solute will decrease the VP, need more heat to boil, so boil at higher T. Boiling Point elevation: more solute, higher the BP. -Freezing point depression: adding solute decreases the FP

In stomach

- Parietal cells in gastric mucosa cells release HCl ->low pH converts pepsinogen(zymogen secreted by chief cell) to pepsin -Food mixed with gastric secretion is known as chyme -pyloric sphincter prevents passage of food from stomach into duodenum. --mediated by nerves connecting duodenum and stomach and hormone cholecystokinin --G cells secrets Gastrin -> stimulates secretion of histamine -> stimulates parietal cells to stimulate acid release

B cells expresses antibodies on their surfaces. When antigens bind to antibody on a specific immature B cell, the cell is stimulated to proliferate and differentiated into plasma cells and memory cells

---plasma cells actively produce and secrete antibody protein into plasma ---memory cells are produced from the same clone and have the same variable region but don't secrete antibodies, dormant, until seeing the same antigens again ->clonal selection

Leukocytes

--All WBC have nucleus and mito ect. --WBC such as macrophages and neutrophils move by amoeboid motility (crawling) --Some wbc directed by chemotaxis **6 types : 1. monocytes: macrophages: phagocytose debris and microorganisms (吞噬碎片) amoeboid motility and chemotaxis 2. lymphocytes: B cell: mature into plasma cell and produce antibodies T cell: kill virus-infected cells, tumor cells, and reject tissue grafts, control immune response 3. Granulocytes: Neutrophils: phagocytose bacteria resulting in pus, amoeboid motility; chemotaxis Eosinophil: destroy parasites; allergic reactions Basophil: store and release histamine, allergic reactions

Ribosomal production

--In eukaryotic cells, in nucleolus, RNA polymerase I functions exclusively to transcribe the pre-ribosomal RNA (rRNA) gene into a single template that is subsequently processed into mature rRNA. As such, the function of RNA polymerase I is restricted to the nucleolus. -Ribosomal proteins are synthesized in the cytoplasm from mRNA and transported into the nucleolus, where they combine with the newly transcribed rRNA to form precursors to the 40S and 60S subunits. These subunits are then shuttled out of the nucleus via nuclear pores and fully mature in the cytoplasm.

parathyroid hormone (PTH)

-controls plasma calcium homeostasis via a simple endocrine reflex. PTH is released in response to decreased plasma calcium and acts on bone, the kidneys, and the small intestine to produce a net increase in Ca and a decrease in P levels. The resulting increase in plasma calcium concentration serves as negative feedback and turns off the reflex, ending PTH secretion. -Stimulating calcitriol synthesis, which then induces absorption of dietary calcium from the small intestine -PTH release increases bone resorption (breakdown) by osteoclasts, bone-resorbing cells, and causes decreased bone mineralization. Osteoclast-mediated bone destruction causes the calcium stored in the matrix to be released into the blood, dissolving mineralized bone and increasing plasma calcium levels.

Chemical vs Electrical Synapse

-electrical synapses: thro ionic current that passes directly from neuron to neuron via a gap junction. instantaneously from one neuron to another. Cytoplasmic continuity also allows signals (ions) to flow bidirectionally across the synapse. -chemical synapses unidirectional, and the cytoplasms of the two neurons are not continuous. Depolarization of the presynaptic neuron results in the release of chemical messengers (neurotransmitters) that diffuse across the synaptic cleft and bind to postsynaptic membrane receptors to generate a new ionic current in the postsynaptic cell. -Signal transmission across chemical synapses is slower than transmission across electrical synapses.

effects of hyperventilation

-increase in blood pH, becomes too basic period of apnea or decrease rate of breathing decrease tidal volume -Increased hemoglobin O2 affinity

The pre-mRNA molecule generally undergoes the ___ modifications --> mature mRNA

1. A 7-methylguanosine (5′ cap) is added to the 5′ end of pre-mRNA -- prevents the degradation of mRNA in the cytoplasm 2. A chain of adenine nucleotides known as the poly-A tail is added to the 3′ end of the mRNA. This poly-A tail functions to prevent the mRNA from being degraded and also facilitates the export of the mature mRNA from the nucleus to the cytoplasm 3. In pre-mRNA, The noncoding regions (introns) are excised from the pre-mRNA molecule, and the remaining untranslated and coding regions are joined via splicing

Duodenal hormones

1. CCK stimulate pancreas and gallbladder to secrete fat digesting enzymes and bile 2. Secretin: causes pancreas to secret H2O and bicarbonate to neutralize HCl 3. Enterogastrone decreases stomach emptying

Hormones Change during a Menstrual Cycle

1. Hypothalamus releases GnRH to stimulate anterior pituitary to release FSH AND LH 2. FSH make granulosa and thecal to develop during follicular phase and secrete estrogen. Secretion of GnRH, FSH AND LH are inhibited by estrogen. But once estrogen reaches threshold, at the end of follicular phase, gives + feedback to LH 3. Increase in LH causes ovulation. After ovulation, LH induces follicle to become corpus luteum to secrete e and p ->secretory phase begin. If pregnancy don't occur ->high of e and p->inhibit GnRH, FSH AND LH->drop in LH->death of corpus ->another menstruation

lipid droplets are transported through the lymphatic system and into the bloodstream as:

1. Lipid droplets are released from the epithelial cells into the interstitial fluid. 2. Lymph capillaries collect lipid droplets from the interstitial fluid. 3. Lymph containing the lipid droplets then flows from the capillaries into increasingly larger lymph vessels. 4. Lymph is then transported into a large tubule structure called a lymph duct, which drains into a large vein near the heart. As a result, the lipid droplets within the lymph enter the bloodstream and circulate throughout the body

Larynx has 3 functions

1. Made entirely of cartilage to keep airways open 2. Contains epiglottis which seals the trachea during swallow 3. Contains vocal cords, which produces sounds o Trachea is the pathway that must remain opened for air to pass, rings of cartilage remains opened for it to not collapse ->then branch into 2 primary bronchi ->each supply 2 lungs o Bronchioles contain no cartilage, made of smooth muscle, adjust diameters to adjust airflow into the system o Terminal bronchioles have really thick walls to allow air diffusion -> no gas exchange allowed

sensory receptors

1. Mechanoreceptors: respond to mechanical disturbances Ex: Pacinian corpuscles: pressure sensor deep in the skin Auditory hair cell in the cochlea of inner cell, detect vibrations caused by sound waves Vestibular hair cell: in semicircular canals in the inner ear, detect acceleration and position relative to gravity 2. Chemoreceptors: respond to particular chemicals such as olfactory or gustatory receptors 3. Nociceptors: pain receptors, stimulated by tissue injury, simplest type of sensory receptor 4. Thermoreceptor: stimulated by change in temp. 5. Electromagnetic receptors: stimulated by electromagnetic

Endocytosis

1. Phagocytosis: non specific uptake large particle into phagocytic vesicle(not invagination) later merge with lysosome 2. Pinocytosis: non specific uptake of small molecules and extracellular fluid via invagination 3. Receptor mediated endocytosis: marked by clathrin and receptors >>coated with a vesicle and brought to endosome then to lysosome. The receptor then can go back to the surface (ex: lipoprotein that contains cholesterol) atherosclerosis>>too much cholesterol in bloodstream

Cardiac muscle has different AP from SA node ->-90mV->longer duration of AP

1. Phase 0: depolarization: caused by increase in Na conductance. Stimulate myocytes to reach threshold for voltage gated Na+ channels ->open->Na flows in 2. Phase 1: initial repolarization :Na+ channel inactive, K+ opens->drop in cell potential 3. Phase 2: plateau phase: increase in potential caused by Na channel open causes Ca2+ channel to open, balance K+ efflux ->transient eq 4. Phase3: repolarization: when Ca2+ channel closed and K+ channel continues to allow K+ to leave the cell. 5. Phase 4: resting potential: inward and outward current equal, channels closed ** Each heart beat begins as an AP in the SA node ->internodal tract->AV node->delayed, then to ventricles (AV bundle, bundle of His)->left and right bundles ->purkinje fibers

¤ Encoding of sensory stimuli

1. Stimulus modality: type of stimulus. CNS determines modality based on which type of receptor is firing 2. Stimulus location: by receptive field of sensory receptor sending the signal 3. Stimulus intensity: coded by the frequency of action potential 4.Stimulus duration: A tonic receptor is a sensory receptor that adapts slowly. A phasic receptor is a sensory receptor that adapts rapidly

2 types of synapses

1. electrical - not common in NS, common in cardiac and smooth muscle. AP spread directly through gap junction 2. chemical: nervous system, end of axon

3 Components are required to regulate BP and HR

1. input(afferent): in the aortic arch and carotid arteries, there are baroreceptors, which monitor pressure. When they notify that CNS that pressure is too high, CNS sends info to increase vagal tone and decrease sympathetic input. 2. Integration: function of CNS 3. Output (efferent)

Liver function

1.Ketogenesis: Ketogenesis (synthesis of ketone bodies) During times of fasting, mitochondria within liver cells convert acetyl coenzyme A into ketone bodies, which are then used by the brain to make ATP. 2. Detoxification of drugs: 3.Synthesis of plasma proteins: Osmotic pressure within capillaries is due to the presence of plasma proteins that cannot easily cross the capillary membrane. Oncotic pressure causes a "pulling force" inside capillaries, which balances the pushing force of hydrostatic pressure, helping keep fluid in the vasculature. The majority of plasma proteins such as albumin are synthesized in the liver.

Nucleoside

5-carbon sugar + nitrogenous base. NO PHOSPHATE groups

Caspase

A "killer enzyme" that plays a role in apoptosis, or programmed cell death

Enhancers

A DNA sequence that recognizes certain transcription factors that can stimulate transcription of nearby genes.

Nucleotide

A building block of DNA, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group.

Hypha

A filament of fungal cells. long filaments of cells joined end to end

Both pro and eu ribosome have A,P, E 3 sites

A: aminoacyl-tRNA site is where each new tRNA delivers its aa. P: peptidyl-tRNA site: where growing polypeptide chain still attached to tRNA E: exit tRNA site: now-empty tRNA sits prior to its release from this site

Wobble hypothesis

Ability of the tRNAs to recognize more than one codon; the codons differ in their third nucleotide. G-U I- A, C, U

parameters influence the thermodynamic stability of the DNA duplex:

DNA length: Longer DNA molecules take more time to both melt and reanneal. pH: Extreme changes in pH outside the physiological range lead to loss of hydrogen bonding and destabilize the DNA helix. Salt concentration (ionic strength): High salt concentration of the solution increases double helix stability, but decreased salt concentration decreases stability.

RNA polymerase

Enzyme similar to DNA polymerase that synthesize RNA strand from DNA

Bone structure (long bone)

Epiphyses are rounded ends that have joint surfaces covered by articular cartilage. The diaphysis is the hollow shaft (medullary cavity) filled with bone marrow. Metaphyses are the regions where the diaphysis and epiphyses meet. The epiphyseal (growth) plate, a cartilaginous structure that lies between the epiphyses and metaphyses, is present only during childhood and serves as the site of longitudinal growth. When growth ceases, the growth plate is replaced with mature bone and is referred to as the epiphyseal line. The periosteum is a thin layer of connective tissue that covers and protects the long bone. (Note: The periosteum does not cover joint surfaces.)

Cap-Independent Translation

Eukaryotic translation usually occurs at the 5' cap since it is monocistronic, BUT sometimes there is an internal ribosome entry site (IRES) where translation can start

Digestion of fat

Fat digestion begins in the small intestine when bile (from the liver) emulsifies it into micelles. After emulsification, lipase (from the pancreas) can then break tri into fatty acids and monoglycerides Once in small instetines, converted back to trigly, packed into chylomicrons -->enter lymphatic capillaries known as lacteals ->merge into thoracic duct ->blood stream ->adipose contains lipoprotein lipase ->hydrolyze chylomicron tri into mono and free fatty acids ->stored as tri

secondary active transport

Form of active transport which does not use ATP as an energy source; rather, transport is coupled to ion diffusion down a concentration gradient established by primary active transport. EX: transport of glucose

synovial joints (diarthroses)

Freely moveable joints consist of several structures that interact with bone and skeletal muscle: -Articular (hyaline) cartilage surrounds the ends of bones within the joint, providing a smooth surface that absorbs compressive forces and reduces friction between bones as they interact. -The joint cavity, located between articulating bones, contains specialized fluid (ie, synovial fluid) that lubricates joint surfaces and protects articular cartilage from excessive friction and damage. -Fat pads are adipose tissue structures present in some synovial joints (eg, knee and hip joints) that provide additional cushion between bones within the joint. -Ligaments and tendons are rope-like, dense connective tissue structures. Ligaments attach bones to other bones whereas tendons generally attach bones to surrounding muscles

Respitory system function

Functions: 1. Regulate pH: CO2 is converted into carbonic acid by RBC enzyme carbonic anhydrase --Hyperventilation: too much breathing decrease of CO2 in bloodRespiratory alkalosis increase in pH -- Hypoventilation: too little breathing increase of CO2 in bloodRespiratory acidosis decrease in pH 2. Thermoregulation: Breathingheat loss through evaporative water loss --some animals manage to conserve water and heat by countercurrent exchange within nasal passage 3. Protection from disease: mucociliary escalator protect us

Microtubular transport

Kinesin: Moves intracellular cargo along microtubules in anterograde axonal transport (ie, away from the nucleus and toward distal sites). Dynein: Participates in retrograde axonal transport of intracellular cargo (ie, from distal sites toward the nucleus)

Retroviruses

MUST ENCODE AND use reverse transcriptase to copy their RNA genome into DNA ---POSITIVE SENSE RNA viruses that undergo lysogeny =RNA dependent DNA polymerase -

(-) RNA viruses

MUST encode and Carry RNA-dependent RNA polymerase

cell cycle

Most cells in the human body are arrested in G0. However, cellular transition into G1 prepares a cell for division and DNA synthesis (S phase). In the G2 phase, DNA is checked for errors and the cell ensures that sufficient organelles and cytoplasm are available for cell division. Subsequently, the cell divides in the M phase via mitosis and cytokinesis. Compounds that inhibit cell division typically target the cell cycle in phases G1 to M.

hyaline cartilage

Most common type of cartilage; it is found on the ends of long bones, ribs, and nose joints lined by hyaline=articular cartilage

Abduction

Movement away from the midline of the body

If the coding strand for a certain gene begins with 5' AGC CTT CGG CTG ACT GGC TGG, which of the following is a possible primer that researchers could use for reverse transcription PCR amplification?

PCR uses DNA primers Pay close attention to polarity (5' vs 3' ends). First, we need to recognize that the sequence given is the coding (sense) strand, not the template (antisense) strand. That means the mRNA that would be produced has the same sequence as the coding strand, except for the thymines which become uracils. So your mRNA will look like 5' AGC CUU etc. Now this mRNA is going to be reverse-transcribed into cDNA for use in PCR, so your cDNA will be 3' TCG GAA etc. Remember, the primer will be complementary to this sequence: so it's (surprise!) going to be 5' AGC CTT...

PCR (polymerase chain reaction)

Polymerase chain reaction (PCR) uses thermal cycling to amplify small DNA fragments -PCR reagents include the following: A source DNA template (containing deoxyribonucleotides) that includes the target region to be amplified and its adjacent flanking sequences -Primer pairs designed from the oligonucleotide sequence of the regions flanking the target sequence -A thermostable DNA polymerase to replicate the DNA template using a pool of supplied (dNTPs) -A buffer solution with positively charged ions (cations) to provide an optimal environment for DNA polymerase to function

anterior pituitary

Release FSH, LH, ACTH, TSH, Prolactin, Endorphins, somatotropin

Microglia (CNS)

Remove cell debris, wastes, and pathogens by phagocytosis

respiratory control center in medulla

Respiration is controlled by the

A band

dark area; extends length of the thick filaments

thrombosis

abnormal condition of a blood clot

varicose veins

abnormally swollen, twisted veins with defective valves; most often seen in the legs

Auxotroph

bacteria need something else to grow

Northern blotting is a laboratory technique used to detect and measure the concentration of specific RNA molecules within a sample.

band intensity denotes quantity of mRNA expression and band location denotes size (smaller molecules appear lower on than larger ones)

Organ of Corti

basilar membrane, hair cells, tectorial membrane

liver synthesizes bile, a nonenzymatic solution stored in the gallbladder

bile salts break down large lipid globules into smaller droplets (micelles) in a process known as emulsification. Emulsification is an example of mechanical digestion, which physically breaks down food particles into smaller pieces. Additional examples of mechanical digestion include chewing in the mouth and churning in the stomach due to peristaltic waves.

Hemostasis

blood clotting

intramembranous ossification

bone is formed directly from fibrous connective tissue (not hyaline cartilage). Mesenchymal (connective tissue) stem cells within this connective tissue differentiate into osteoblasts and secrete the bone matrix.

Hypothalamus

brain region controlling the pituitary gland, Regulates the autonomic nervous system via the endocrine system. Produce LH, FSH, ACTH, TSH

fascicle

bundle of muscle fibers

Conjugation mapping

by allowing Hfr cells(A cell that has its F factor integrated into its genome) to conjugate in lab and stoping the conjugation process after different time intervals, they can decide the order of genes

Adaptive radiation

divergence of one species into multiple species over time, which can occur when subgroups of the original species are separated or isolated in different environments so that these subgroups evolve independently of one another.

The segments of the small intestine include

duodenum, jejunum, and ileum. The pyloric sphincter is a muscular ring located at the junction of the stomach and the duodenum. This sphincter controls the flow of chyme, or partially digested food, from the stomach into the duodenum.

GI tract

composed of the esophagus, stomach, small intestine, and large intestine. Upon ingestion, food is broken down in the mouth by amylase and lingual lipase packed into bolus and travels down the esophagus to the stomach where chyme is formed and enters the small intestine. -In the small intestine, intestinal and pancreatic enzymes break down macromolecules, which are then absorbed via diffusion through absorptive cell membranes or through intestinal transporters. -Next, food enters the large intestine, the site where additional water absorption occurs and where microbial communities (gut flora) synthesize vitamins and metabolize remaining carbohydrates.

Atherosclerosis

condition in which fatty deposits called plaque build up on the inner walls of the arteries

brainstem function

consists of medulla, pons, and midbrain origin of most cranial nerves, contains reticular formation (important for arousal, sleep-wake cycles), location of respiratory, cardiovascular, and digestive control centers

Endotoxins

contains lipopolysaccharide, components of the outer membrane of gram-, cause immune system to release chemicals that causes us septic shock: many blood liquid released into tissues and cause low bp

I band of sarcomere

contains only thin actin filaments

Type I (slow twitch)

Slow Oxidative (SO) • Produce low contractile force • Efficient aerobic metabolism • Highly vascularized • High myoglobin (this is the red part) • Oxidize fat • Fatigue resistant • Many mitochondria (produce energy) -Skeletal muscle fibers (cells) can be identified as type 1 (slow oxidative), 2A (fast oxidative-glycolytic), or 2X (fast glycolytic); this classification is based on two features of muscle fibers: Their contractile speed (fast or slow): Contractile speed is determined largely by the catalytic speed of the myosin ATPase and the activity of the associated motor neuron at the neuromuscular junction. Their primary means of producing ATP (oxidative or glycolytic): To generate ATP, oxidative fibers use aerobic respiration, but glycolytic fibers use anaerobic glycolysis.

Seminiferous tubules

Small convoluted tubules in the testes where spermatogenesis takes place.

Thalamus function

Somatic sensory relay station

hypothalamic-pituitary-adrenal pathway

controls the secretion of glucocorticoids from the adrenal cortex as follows: The hypothalamus secretes corticotropin-releasing hormone (CRH) in response to low glucocorticoid levels and increased stress. CRH acts on the anterior pituitary, which causes the release of adrenocorticotropic hormone (ACTH). ACTH stimulates the adrenal cortex to synthesize and release cortisol. Cortisol targets tissues (eg, muscle and liver) to increase the ability to cope with stressors. In addition, cortisol functions as a negative feedback signal by inhibiting the secretion of CRH and ACTH.

gene expression

conversion of the information encoded in a gene first into messenger RNA and then to a protein -can be analyzed by: Northern blotting Southern blotting Reverse transcription PCR NOT WEST

Conjugation uses F factor (Gram-negative )

The process of conjugation involves production of a special conjugation pilus (sex pilus) by one bacterium and transfer through it of DNA to another bacterium. It requires special genes for the pilus and these are usually present on a plasmid, a separate extragenomic strand of DNA not incorporated into the bacterium's own DNA. This plasmid is referred to as the fertility or F factor. Conjugation is a feature of Gram-negative bacteria. It confers the advantages of sexual reproduction on the bacterium. The plasmid benefits by being able to move from one host bacterium to another through the conjugation pilus.

parallel evolution

Two related species that have made similar evolutionary adaptations after their divergence from a common ancestor

Oligodendrocytes

Type of glial cell in the CNS that wrap axons in a myelin sheath.

amber codon

UAG stop codon

Myosin

thick filament

H zone

thick filaments only

actin

thin filaments

Cardiac muscle is a functional syncytium

tissue in which cytoplasm of different cells can communicate via gap junctions(found in the connections between cardiac muscle cells ->intercalated discs) ->electrical synapse

lytic cycle

to rapidly increase number but destroys all host cells): first make an early gene: hydrolase: a hydrolytic enzyme that degrades the entire host genome ---then each new capsid assembles itself around a new genome then ---late gene: lysozyme: destroys bacteria cell wall and cause it to burst

Skin

top: epidermis (epithelial tissue) -> dermis (connective tissue) -> hypodermis (adipose tissue) § Epidermis: composed of stratified(many layers) squamous epithelial cells -> constantly replaced -> also contains keratin (tough and hydrophobic) make skin water proof -> contains melanin, produced by melanocytes -> absorb UV light prevent damage of underlying tissues § Dermis: contains blood vessels that nourish both dermis and epidermis -> also contains sensory receptors, sudoriferous (sweat glands), sebaceous (oil glands), and hair follicles -> sweat is to allow loss of excess heat through evaporation -> Some skin contains ceruminous (wax) glands Aldosterone prevent excess loss of sodium

RNA polymerase II

transcribes mRNA

RNA polymerase I

transcribes rRNA

Exotoxins

very toxic, by both + and -. Cause botulism, diptheria, tetanus, and toxic shock syndrome

divergent evolution

when two or more species sharing a common ancestor become more different over time

Spirometry

§ Tidal Volume (TV) = volume of air entering the lung (inspiration) or the volume of air leaving the lung (expiration § Inspiratory Reserve Volume (IRV) = maximal amount of air that can be inspired above tidal volume. § Expiratory Reserve Volume (ERV) = maximal volume of air expired after normal expiration. § Functional Residual Capacity (FRC) = volume remaining in the lung after a normal expiration. [approx. 2.5L]. § IC: inspiratory capacity: max volume of air which can be inhaled after a resting expiration § Residual volume (RV) = volume of air at end of maximal expiration. § Vital capacity (VC) = the maximal amount of air that a person can expire after maximal inspiration. TLC: total lung capacity: VC+RV

Endocrine Pancreas

¨ Consists of small regions within pancreas: islets of Langerhans ¨ 3 types of cells in islets: 1. cells secrete glucagon in response to low blood sugar stimulate liver to hydrolyze glycogen and release glucose into blood 2. cells secrete insulin in response to elevated blood sugar removes of glucose store as glycogen 3. cells secretes somatostatin inhibits digestive process

Development of Male Reproductive System

¨ Early embryos both have Wolffian ducts that can develop into male internal genitalia (epididymis, seminal vesicles, ductus deferens) and Mullerian ducts for female internal genitalia (uterine tubes, uterus, vagina) ¨ In the absence of Y chromosome, Mullerian ducts develop by default. Female external genitalia (labia, clitoris) also develops by default. ¨ Y chromosome leads to the producing of testosterone and MIF ->development of testes -> male external and internal develop ¨ MIF->regression of Mullerian ducts ->no internal female g ¨ Testosterone secreted around 7 weeks. Testes formed by week 9 ¨ Testosterone for external g has to enter systematic circulation and converted to dihydrotestosterone. Gonads becomes either testes or ovaries

exocrine pancreas

¨ Pancreatic amylase: hydrolyzes poly to disaccharides ¨ Pancreatic lipase hydrolyzes triglyceride ¨ Nuclease: hydrolyze dietary DNA and RNA ¨ Some Pancreatic proteases hydrolyzes poly to tri or dipeptide ¨ They are in inactive zymogen form. ¨ CCK and Secretin control the activity of pancreas

Saliva contains

¨ Salivary amylase (ptyalin) hydrolyze starchonly into disaccharide ¨ Also contains lingual lipase: fat digestion ¨ Also contains lysozyme to break bacterial cell wall ¨ Pack food into bolus

Development of Female Reproductive System

¨ XX causes formation of ovaries which secrete estrogens ¨ In males, testosterone causes labioscrotal swellings to form scrotum. For females, labioscrotal swellings forms labia majora. Instead of penis, clitoris develops. ¨ Female internal genitalia (vagina, uterine tubes, uterus) derived from Mullerian Ducts.

Fertilization

· A secondary oocyte is ovulated and enters uterine tube. It is surrounded by zona pellucida then corona radiata then. The oocyte will remain fertile for 1 day. · Sperm will be deposited near cervix and activated =capacitated. Sperm capacitation needs dilution of inhibitory substances in semen. The activated sperm will survive for 2 or 3 days. They swim through uterus towards the secondary oocyte. · Fertilization happens in uterine tube. Sperm must penetrate corona radiata then zona pellucida. By acrosomal reaction. Acrosomal process contains bindin which binds to receptor on zona >then egg and sperm fuse. Then oocyte >2nd meiosis >ootid and secondary polar body. Ootid then becomes ovum. Then 2 nuclei fuse >zygote.

· Fast block and slow block prevent polyspermy.

· Fast block: depolarization of egg plasma membrane prevent other sperm bind. · Slow block=cortical reaction: Ca influx caused by initial depolarization causes swelling of space between zona and plasma membrane and harden and egg activationincrease metabolism and protein synthesis.

Golgi apparatus

· Functions: modification of proteins made in RER (ex add oligosacc), sorting and sending proteins to destinations, synthesize certain macromolecules (polysacc) · Part close to ER: cis Far from ER: trans · Vesicle from golgi is unidirectional (enter at one region and exit at another) · Retrograde traffic: from golgi to ER · Anterograde: forward, from RER to golgi to cell surface or other target within cells.

pregnancy

· Maternal respiratory rate increase to bring more O2. Blood volume increase, increase glomerular filtration rate. release of renin and erythroprotein

Development of follicle

· Primary oocyte + granulosa cells =follicle ->primordial follicle · As primordial follicle matures, it form zona pellucida. Several follicles are separated by thecal cells. Only one follicle progress to mature to ovulation each month. All others degenerate. · Mature follicle =Graafian follicle. · During ovulation, Graafian follicle bursts, release secondary oocyte with its zona pellucida and protective granulosa cells into fallopian tube. -granulosa layer surrounding ovum known as corona radiata. · The follicular cells remaining in the ovary after ovulation forms corpus luteum. · During first half of menstrual cycle, estrogen is made and secreted by granulosa cells. · During second half of menstrual cycle, estrogen and progesterone is made and secreted by corpus luteum.

Hardy-Weinberg Principle

· allele frequency wont change over time->assume no mutation, no migration, no natural selection, population large to prevent random drifting, random mating

Spleen

filters blood, immune cell interactions

Prion

is a misfolded existing protein -self replicating --Infect cells by making host proteins misfolded too --cause destruction of neurons, particular in central nervous system -disease: TSE

open reading frame (ORF)

is a portion of a reading frame that can be translated by ribosomes because it contains both a start codon (AUG) and a stop codon (UAA, UAG, or UGA) within the same reading frame

Negative-sense viral RNA

is complementary to mRNA and thus must be converted to positive-sense RNA by an RNA polymerase before translation, must carry RNA dependent RNA poly

Antibiotic resistance

is often investigated using the agar diffusion test in which disks impregnated with different antibiotics are placed on a bacterial culture. Susceptible bacteria normally form a growth-free halo called a zone of inhibition around the disks due to the high antibiotic concentrations. However, resistant strains can grow near that antibiotic and do not form a zone of inhibition.

Mycelium

meshwork of hyphae

brain stem

midbrain, pons, medulla relay info to or from cerebellum and cerebrum

myomentrium

middle layers of smooth muscle in uterus

Mesophiles

moderate temperature loving

Sliding filament model of muscle contraction

myosin head start with empty ATP binding site, bind to single molecule of actin within thin filament 1. ATP bind to binding site in myosin head -> conformational change of head -> let go of actin 2. ATP hydrolysis -> release of actin hydrolyze ATP molecule ->that energy cause head to move forward but hasn't release any products ***head binding still to ADP and Pi(spring loaded high energy conformation) 3. Head now binding weakly to a different molecule of actin (a few positions closer to z disk, closer to the end of sacomere) 4. Phosphate group is released->trigger the power stroke-> generate muscle contract force->transient intermediate ->head grab tightly to actin 5. Power stroke ->myosin head spings back->this pulls thin filament back ->pulls z disk 6. Myosin head release ADP ->back to original, myosin bind to an actin->but now, it is attached to a actin that is closer to Z disk or thin disk is pulled closer to the center of sarcomere Overall sarcomere is contracted

divergent selection

natural selection removes members near the average, split population in two

appendix

near the begin of large intestine, has WBC

sensory neurons (afferent)

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

motor neurons (efferent)

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

expiration

no need of contraction, caused by elastic recoil of lungs

2 sites for protein synthesis

o 1. On ribosomes in Cytoplasm>proteins toward peroxisomes, mito, nucleus, or cytoplasm 2. On ribosomes in Rough ER>secreted to extracellular, integral membrane proteins, in membrane or interior of ER, golgi apparatus, lysosome

Lysosome

o Membrane bound organelle for degradation of bio macromolecules by hydrolysis o Made in RER, modified in golgi, released from trans of golgi. o Autophagy: eating cell organelles o Phagocytosis: degrade large particles such as fuse phagocytic vesicle that contains macrophages of bacteria o Crinophagy: digesting excess vesicles, secretory particles. o Acid hydrolases: enzyme used for degradation. pH of activation of it is 5, which is pH of lysosome. So it will be safe for cytoplasm

bone remodeling

osteoclasts break down (resorb) old bone and osteoblasts deposit new bone. Specifically, osteoblasts promote the precipitation of calcium and phosphate from the bloodstream and their transfer and incorporation into the bone matrix. osteoclasts secrete acids that break down the mineral components of bone, releasing calcium and phosphate into the bloodstream.

adrenal cortex

outer section of each adrenal gland; secretes cortisol(long term stress response), aldosterone-->kidney to increase Na reabsorption to increase BP, and sex hormones

autonomic nervous system (ANS)

part of the peripheral nervous system Its sympathetic division arouses; its parasympathetic division calms.

bacteria cell walls are made of

peptidoglycan--can be destroyed by lysozyme made by lytic viruses

G-C base pairs form stronger π-stacking interactions than A-T base pairs, thereby creating the most thermal stability.

pi stacking is improved in GC because of the extra H-bond that resists changes in rotation thus decreasing strain and increasing the strength of the pi stacking

Osmotic pressure

pi=MiRT

AP is initiated when

postsynaptic membrane reached threshold depolarization required to open voltage gated sodium channel. --postsynaptic neurons has other many different neurons with synapses leading to it. Whether to fire AP or not depends on adding all these synapses together

Pulmonary edema

pressure increase in left atrial pressure ->pressure in capillaries increase -> fluids will be forced out of the capillaries into lungs -> decrease O2 diffusion Lymphatic system prevents pulmonary edema from developing by carrying interstitial fluid out of lungs

Myofibrils

protein structures that make up muscle fibers (myofibers)

Rough ER function

protein synthesis for proteins targeted to enter secretory pathway - initial post-translational modification of proteins, disulfide bond formation, glycosylation(also in golgi apparatus )

fibrin

protein that forms the basis of a blood clot -----plasma protein fibrinogen is converted to fibrin by thrombin ---thrombus: blood clot, is a scab circulating in the bloodstream

semilunar valves

pulmonary valve: between the right ventricle and the pulmonary trunk aortic valve: between the left ventricle and the ascending aorta

primary active transport: directly use ATP: Na/K ATPase

pump 3Na out and 2 K in and hydrolyze one ATP to pump ions against concentration gradient. Na cant go back to cell but K can be out thro leak channels. So inside the cell will be more negative. >>resting membrane potential , also maintain osmotic balance, provide concentration gradient to drive secondary transport. ---Secondary active transport: not coupled directly to ATP

Midbrain

relay for visual and auditory info and contains reticular activating system: responsible for arousal and wakefulness -eye movement

posterior pituitary

release ADH(vasopressin) increase water reabsorption release Oxytocin ---both peptide

epiphyseal line

remnant of the epiphyseal plate, seen in adult bones, e and d fused together ->stopped growing

driving force for DNA replication and transcription

removal and subsequent hydrolysis of pyrophosphate from each nucleotide added to the chain, with existing chain act as nucleophile

posterior lobe of the pituitary gland

secretes Vasopressin(ADH)(reabsorb water and drink water to decrease osmotic pressre) and oxytocin (uterine contraction and milk)

Medulla

secretes epinephrine and norepinephrine in response to short-term stress. Reactions to short-term stress are mediated by the sympathetic branch of the autonomic nervous system.

epithelial cells in the respiratory tract

secretes mucous

Vasodilation and vasoconstriction regulated by

secretion of nitric oxide or endothelin

accessory glands

seminal vesicles, prostate gland, bulbourethral glands

Interoception

sensory information arising from within the body, such as hunger and thirst ex: aortic arch baroreceptors pH receptors

analogous structures

similarities among unrelated species that result from convergent evolution

Cardiac muscle: some of Ca comes from extracellular, functional syncytium bc muscle cells are interconnected by gap junctions (intercalated disks) Skeletal muscle: Ca comes from Sarcoplasmic reticulum and is syncytial Smooth muscle doesn't have T tubule, no sarcomeres, contraction regulated by calmodulin and MLCK, not myosin and tropomyosin, have constantly fluctuating resting potential, have slow waves -> help get the potential closer to threshold --slow wave is increased by ACh, decreased by NE

smooth and cardiac are connected through gap junctions, both rely on EC Ca

o Pleural space

space in between them, the pressure here( pleural pressure) NEGATIVE -> these 2 membranes are drawn together ->lung surface drawn to the chest wall. Also, a thin layer of fluid draw them together by surface tension

promoter

specific region of a gene where RNA polymerase can bind and begin transcription

M line

supporting proteins that hold the thick filaments together in the H zone, center of sarcomere

DNA primase

synthesizes a short RNA primer to provide a 3'-OH group for the attachment of DNA nucleotides

adrenergic tone

the constant level of norepinephrine released by millions of sympathetic postganglionic axons innervating precapillary sphincters -->sympathetic activation causes precapillary sphincters in the gut to contract, while arterioles supplying skeletal muscles relax->blood into skeletal muscle to allow for fight or flight

somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles--voluntary

Skeletal muscle and cardiac muscle have T tubules, smooth muscle dont

T-TUBULES is to conduct impulses from the surface of the cell (SARCOLEMMA) down into the cell and, specifically, to another structure in the cell called the SARCOPLASMIC RETICULUM

In neurons, action potential propagation occurs along the axon. The analogous structure in skeletal muscle fibers that enables action potential propagation is the:

T-Tubule

respiratory alkalosis

high pH, low CO2, hyperventilation

systolic pressure

highest pressure during when ventricles contract

CNS

hindbrain, midbrain, forebrain+ spinal Cord

z lines

hold the thin filaments together in I band. The ends of a saromere.

Myoglobin

holds oxygen in the muscles and organs only one binding site

tropic hormones

hormones that stimulate other glands to release their hormones

Cartilage types

hyaline, elastic, fibrocartilage Cartilage is a connective tissue composed of cells known as chondrocytes that secrete an extracellular matrix called chondrin, which contains collagen fibers, proteoglycans, and water. -hyaline cartilage is the most abundant, is found on the ends of long bones as well as in the ribs, nose, trachea, and larynx. cartilage lacks nerves (ie, is not innervated) and is avascular (ie, lacks its own blood supply), it must receive nutrients and oxygen via diffusion from surrounding fluids or vascularized areas -The process of endochondral ossification utilizes hyaline cartilage as a template for bone deposition.

Testosterone stimulates the division of spermatogonia. LH stimulates interstitial cells to secrete testosterone. FSH stimulates Sertoli cells, which secretes inhibin to inhibit FSH release

Testosterone regulates testicular activity by inhibiting GnRF release from the hypothalamus and LH release from the pituitary.

Haustoria

hyphae specialized to absorb and digest nutrients like parasite

appetite is controlled by

hypothalamus

edema

increased fluid in body tissues, cause is a decrease in the plasma protein level. --Also occur during inflammation, more WBC into tissues --This occurs, for instance, in starvation when the body is forced to use its albumin as an energy source. An increase in the plasma protein level would have the opposite effect: fluid would enter the bloodstream

Increase of blood osmotic pressure

increases the return of fluid to the circulatory system from the body tissues

pressure can be changed from

increasing the force or rate of cardiac contraction

3 types of immunity

innate, humoral, cell-mediated

endometrium

inner lining of the uterus, shed every month

If two genes are located close together on a chromosome

less recombinant progeny of them

There are no viable autosomal monosomies, and the only viable autosomal trisomies you should know are Trisomy 21, 18, and 13 (though Trisomy 8, 9, and 22 can also survive to term).

Aneuploidy results from having too many or too few copies of a given chromosome. This results from nondisjunction in anaphase during cell division. Having only one copy of a chromosome is known as monosomy, and having three copies is known as trisomy.

Endosomes

Another name for vesicles, especially in terms of endocytosis

Fertilization and implantation

--Once the egg is ovulated from the ovary it enters into the oviduct (fallopian tube). It is in the oviduct that the egg may be fertilized by a sperm. After fertilization, the cell is now called a zygote. The zygote undergoes cleavage division in which the DNA is copied and cleavage divides the cell into two identical cells. Cleavage is a special type of mitosis. During cleavage division, the cell mass does not enlarge, but rather the number of cells increases with each new cell being smaller than the original one. Cleavage divisions continue until the cell mass takes on a hollow ball formation with an inner cell mass. This stage is called a blastocyst. The inner cell mass is made up of identical cells (called stem cells) that are undifferentiated. The blastocyst travels down the oviduct and into the uterus where it will implant into the endometrium and begin developing into an embryo. --Typically, small hair-like structures within the fallopian tube called fallopian cilia help propel the fertilized oocyte toward the uterus for implantation. However, without an adequate number of cilia in the fallopian tube, improper implantation of the fertilized egg can occur outside the uterus.

Ribosomes

--Ribosomes are molecular machines that translate mRNA sequences into proteins. All ribosomes are composed of ribosomal proteins and ribosomal RNA, but their structure differs in eukaryotes and prokaryotes: **Eukaryotes produce 80S ribosomes composed of a 60S large subunit and a 40S small subunit. **Prokaryotes produce 70S ribosomes composed of a 50S large subunit and a 30S small subunit. --Ribosomes synthesize proteins in either the "free" state in the cytoplasm or the "bound" state when attached to the rough endoplasmic reticulum (ER). Initially, a signal sequence within the target mRNA bound to the ribosome is translated into a signal peptide that induces transport of the ribosome-mRNA complex to the rough ER. The complex synthesizes proteins into the lumen of the rough ER, which then assembles and modifies secretory, lysosomal, and integral membrane proteins.

autonomic PNS Anatomy

--The efferent of para(craniosacral system) and sympathetic(thoraco-lumbar) systems consist of 2 neurons preganglion and postganglion --pre has cell body in brainstem or spinal cord. It sends axons to an autonomic ganglion in the outside of spinal cord. In the ganglion, it synapse with post ganglionic neuron. The post sends an axon to an effector (smooth muscle or gland) --All pre uses ACh, all post in para system use ACh, all post in sym uses NE. --All sympathetic preganglionic efferent neurons have cell bodies in thoracic(chest) or lumbar (lower back) regions of spinal cord --All para sympathetic preganglionic efferent neurons have cell bodies in brainstem or lower portion of spinal cord. --Sympathetic Preganglionic axon is short, ganglia close to cord, far from target, post is long --Para Preganglionic axon is long, ganglia far from cord, close to target,post is short --Autonomic afferent can synapse in PNS: short reflex

blood vessels

--all three types of vessels possess an inner layer of endothelial cells. --only veins have valves. --only certain types of arteries dilate or constrict to regulate blood flow. --exchange of nutrients with the surrounding tissues occurs only in capillaries.

blood pressure regulation (urine)

--angiotensin II, aldosterone, and antidiuretic hormone (ADH; vasopressin) regulate BP by modulating the kidney's reabsorption of water and salts. --1. The renin-angiotensin system (RAS) is a multi-organ molecular cascade activated when BP (or blood volume) falls. A drop in BP causes the juxtaglomerular cells in the kidneys to release renin, an enzyme that cleaves the plasma protein angiotensinogen to form angiotensin I. Angiotensin-converting enzyme (ACE) then cleaves angiotensin I to form angiotensin II. Angiotensin II ultimately raises BP by inducing both the release of aldosterone from the adrenal cortex (increasing BP by increasing blood volume through water retention) and the constriction of arterioles (increasing BP without changing blood volume) -Aldosterone is released in response to RAS activation or to an increased serum level of K+. Aldosterone acts on the distal tubules and collecting ducts of nephrons to promote the reabsorption of Na+ and the secretion of K+. Increased reabsorption of Na+ increases the osmolarity of the renal interstitial fluid. Elevated osmolarity promotes water reabsorption. 2. ADH is released by the posterior pituitary when BP falls or when blood osmolarity rises. ADH promotes water reabsorption by increasing the permeability of the distal tubule and collecting duct to water. ADH also induces vasoconstriction, the narrowing of blood vessels.

How do antibodies remove antigens?

--binding of antibodies can directly inactivate antigen --binding of antibody can induce macrophages and neutrophils --can activate complement system to form holes in cell membrane and lyse

Fungi

--multicellular except for yeast --Have chitin in their cell wall --Chemoheterotrophs --Most are either saprophytes: eat dead Or parasites or mutualists --Most are obligate aerobes, doing absorptive: digestion of nutrients take place outside of fungal cell --reproduce asexually or sexually --Has specialized region called gametangia: can either produce and release gamates to fuse with other gamates or fuse with gametangia from other fungi

Making a n# aa chain needs 4n phosphate bonds to be broken

-2 P bonds hydrolyzed per aa to make aminoacyl-tRNA -2 required for each elongation

Eq potential for K+

-90mV

Haversian system

-A shell of cortical (compact) bone generally surrounds cancellous (spongy) bone. -Compact (hard) bone is organized into osteons, or haversian systems, which are made up of lamellae (concentric rings of bone matrix) that surround a central haversian canal, a cylindrical channel that runs parallel to the long axis of bone and through which blood vessels and nerves traverse. Volkmann canals, which run perpendicular to the long axis of bone, allow the passage of blood vessels and nerves between different haversian canals. -osteogenic (osteoprogenitor) cells, osteoblasts, osteocytes, and osteoclasts. -During bone remodeling, old bone is resorbed (broken down) by osteoclasts and new bone is deposited by osteoblasts. -Osteogenic cells are the mitotically active stem cells in bone that initially differentiate into osteoblasts. The osteoblasts then secrete the proteins that form the unmineralized bone matrix called osteoid. Although it is primarily composed of collagen, osteoid eventually becomes mineralized through the precipitation of calcium salts on the surfaces of its collagen fibers. These deposited calcium salts mature into hydroxyapatite crystals, the mineral responsible for bone hardness. Osteoblasts continue to build successive concentric layers of bone, but as the osteoid mineralizes, some osteoblasts become trapped within lacunae (spaces) in the lamellar matrix and are known as (mitotically inactive) osteocytes at this stage. -Within each osteon of compact bone, lacunae connect to one another via microscopic channels called canaliculi, which allow osteocyte waste exchange and nutrient delivery

Inducible enzymes

-An enzyme whose transcription can be stimulated by an abundance of its substrate (as opposed to repressible enzyme). Usually in catabolism. 2 ex: lac operon(inducible, part of lactose catabolism) and trp operon(repressible, encodes for Trp anabolism) -Under normal conditions, they are bonded to a repressor. They are turned on when an inducer pulls the repressor off.

Kidney Function

-Control of extracellular fluid volume & regulation of blood pressure via the renin-angiotensin system Regulation of osmolarity (ie, excretion or retention of water) -Regulation of ion concentration (Na+, K+, Ca2+) by balancing dietary ion intake with urinary excretion -Regulation of pH via bicarbonate buffer system (excretion/retention of HCO3− and H+) When extracellular fluid (eg, blood plasma, interstitial fluid) becomes excessively alkaline (high pH), the kidneys excrete HCO3− and retain H+, causing blood pH to decrease. Conversely, when the extracellular fluid becomes excessively acidic (low pH), the kidneys excrete H+ and retain HCO3−, causing blood pH to rise. -Excretion of waste (creatinine, ammonia, urea, foreign substances) -Production of renin (enzyme involved in blood pressure regulation) & hormones (erythropoietin for erythrocyte production & calcitriol using VitD for increased Ca2+ levels) -Erythropoietin production: The adult kidneys normally produce erythropoietin, a hormone that signals the bone marrow to increase red blood cell (erythrocyte) production.

Corticosteroid hormones secreted by the adrenal cortex

-Glucocorticoids (eg, cortisol): Increase energy availability by stimulating lipolysis & gluconeogenesis (synthesis of glucose from noncarbohydrate sources such as amino acids); also, have anti-inflammatory effects -Mineralocorticoids (eg, aldosterone): Affect salt & water homeostasis in the kidneys by promoting sodium reabsorption & excretion of potassium

Glomerular Filtration Rate (GFR)

-Higher hydrostatic (blood) pressure in the glomerulus increases GFR, and lower hydrostatic pressure decreases GFR. -narrowing of the afferent arteriole would cause an increase in resistance because of the reduced diameter of the afferent arteriole. When resistance within the afferent arteriole is increased, blood flow to the glomerulus is expected to decrease

regulation of body temperature

-In cold environments, sympathetic signaling causes contraction of the arrector pili muscles, which causes piloerection (hairs standing upright). -> impedes heat loss by trapping heat near the skin surface -When body temperature is above normal, Vasodilation (widening) of skin arterioles increases blood flow to skin capillaries and maximizes heat loss through the skin.

Bacterial life cycle

-Lag phase (cell division not occur)->log phase(grow exponentially)->stationary phase (cease to divide when no nutrients->death phase -Carrying capacity max population at stationary phase

Type II (fast twitch)

-Rapidly develop force -High peak force -Low capacity for oxidative metabolism -Fatigue easily -Sprint, short-term performance

Humoral immunity

-Specific protections by proteins in plasma called Ab=Ig -Each antibody contains 2 copies of 2 different polypeptides, the light chains and heavy chains, each antibody has one constant region and one variable region ** IgG, IgA, M, D,E

When blood glucose levels are low

-The pancreas alpha releases glucagon, which eventually causes blood glucose levels to increase. -autonomic nervous system promotes the release of epinephrine and norepinephrine by the adrenal medulla. Glucagon is a peptide hormone that promotes gluceoneogenesis and glycogenolysis (the breakdown of glycogen into glucose). Epinephrine and norepinephrine also promote glycogenolysis.

Oogenesis

-involves mitosis and two meiotic divisions. Oogenesis begins in utero at approximately 4 weeks gestation. In the female embryo, oogonia (germ cells) are diploid stem cells that first multiply quickly via mitosis and become primary oocytes. The primary oocytes then commence the first meiotic division but become arrested at prophase I. From infancy to puberty, the ovaries are functionally inactive. The chromosome pairs are arranged in a tetrad during this phase, and their proximity allows for genetic recombination. At puberty, ovulatory cycles begin, and the female is capable of reproduction. During each menstrual cycle, stimulation by follicle-stimulating hormone (FSH) followed by a surge in luteinizing hormone (LH) causes some primary oocytes to resume meiosis I. The last stage of meiosis I (telophase I) in a primary oocyte yields two unevenly divided haploid cells. One cell is the secondary oocyte, which has almost all the cytoplasm of the primary oocyte; the other is the first polar body, which is smaller (The amount of nuclear material in each, however, is the same) and does not develop into a mature oocyte. The secondary oocyte begins meiosis II, but it halts in metaphase II and the polar body degenerates. The secondary oocyte remains frozen in metaphase II until fertilization occurs, at which point it completes its second meiotic division (telophase II) into an ootid and second polar body. The zygote that results from fertilization is diploid due to genetic contribution from both the ovum and sperm nuclei.

Lac operon

-operon required for the transport and metabolism of lactose in bacteria 1. P region: promoter site on DNA which RNA polymerase binds to initiate transcription of Y,Z,A 2. O region: operator region to which Lac repressor binds 3. Z gene: encodes for Beta-galactosidase, which cleaves lactose into glucose and galactose 4. Y gene: codes for permease, transfers lactose into the cell 5. A gene: codes for transacetylase, transfers an acetyl group from acetyl CoA to Beta-galactosidase 6. Crp gene: located at a distance site, codes for a catabolic activator protein (CAP) and help couple the lac operon to glucose in the cell. 7. I gene: located at a distance site, codes for Lac repressor § When glucose is high, AC is inactivated and cAMP level low. § When glucose is low, CAP binds to cAMP, this complex binds to promoter->activate RNA polymerase at lac operon ->turned on. § I gene codes for repressor, which binds to operator of lac operon->prevents binding of RNA polymerase to promoter. The repressor can also bind to lactose, which blocks its activity on operator (allosteric binding, distant from operator binding)

Lysogenic cycle

-phage genome integrates into bacterial genome ->this is called prophage, host is called lysogen ---prophage is silent, genes not expressed, viral progeny not produced ---bc phage genes are blocked by phage-encoded repressor protein that binds to phage promoters ---excision: when prophage is activated and removed from the host genome and **will take part of the host genome with it ->transduction (foreign DNA is introduced into a host)

Desmosomes

-provide tensile strength to epithelial cell sheets by anchoring the cytoskeletons, specifically the intermediate filaments, of two cells together. This creates a continuous cytoskeletal network that spans the entire epithelial sheet, one through which mechanical stress (eg, pulling, stretching, tension) can be distributed. -Desmosomes are found predominantly in tissues that are subject to high levels of mechanical stress

SDS-PAGE

-sodium dodecyl sulfate polyacrylamide gel electrophoresis -SDS-PAGE is used to separate proteins by molecular weight. During the procedure, SDS coats proteins with a negative charge. An electric current is then applied, and smaller and more compact proteins travel through a polyacrylamide gel and toward the positive anode faster than larger ones, creating lanes of size-separated protein bands.

Temperature Regulation by Skin

1. Contraction of skeletal muscle 2. Skin insulate us, and we generate heat by metabolism 3. Heat loss by conduction is minimized by blood vessel constriction in dermis (cutaneous vasoconstriction) in response to activation of sympathetic nervous system Dissipation of excess heat by 1. Sweat 2. Dilation of blood vessels in the dermis (cutaneous vasodilation) results in heat loss by conduction or convection

Ways to increase contraction

1. Decrease transport of Ca2+ to the extracellular environment. 2. Increase availability of intracellular Ca2+ to bind to troponin. 3. Increase overall Ca2+ stores in the sarcoplasmic reticulum.

diastole vs systole

1. Diastole: --atria contracts, ventricles relaxed, blood able to flow into them from atria, at the end of diastole, ventricles contract, initiating systole ->AV shut Systole: pressure in ventricle increases rapidly, until semilunar valves open and blood flows into pulmonary artery and aorta->period when ventricle contracting and beginning lub sound, ending at dup.

Duodenal Enzymes

1. Enterokinase activates pancreatic zymogen trypsinogen to trypsin 2. Brush border enzymes hydrolyze into monosacc and aa

4 types of tissues in animals

1. Epithelial 2. Connective 3. Muscular 4. Nervous

spleen function

1. Filters senescent (worn-out/aged) or damaged red blood cells (RBCs) from the blood. (liver is also involved in the removal and reuse of aged RBCs.) 2. Serves as a reservoir for blood, which can be released in the event of a sudden drop in blood volume. 3. Participates in immune function by housing macrophages that phagocytize and destroy foreign substances and by serving as a site of B cell activation

countercurrent exchange in loop of henle

1. Filtrate flows through the descending limb of the loop, which is highly permeable to water but impermeable to NaCl. because salt concentration in the medulla is high, water is passively reabsorbed from the filtrate flowing through the descending limb into the salty medulla, where it is taken up by blood vessels. 2. Filtrate then flows into the ascending limb, which is highly permeable to NaCl but impermeable to water. Initially, NaCl is passively reabsorbed into the medulla as filtrate moves up the ascending limb. However, as the ascending limb nears the cortex, NaCl is actively transported from the filtrate into the medulla, preserving the medulla's high salt concentration. Because water follows NaCl, the saltiness of the medulla promotes continued water reabsorption from the descending loop of Henle and the collecting duct. -Following passage through the loop of Henle, filtrate travels through the distal tubule into the collecting duct, where water and salt reabsorption continue. Remaining filtrate flows to the bladder and is excreted from the body as urine.

cerebral cortex

1. Frontal lobes: initiate voluntary movement and complex reasoning and problem solving 2. Parietal lobes: sensations and gustation 3. Temporal lobe: auditory and olfactory 4. Occipital lobe: visual

Cell-mediated immunity

1. T-helpers: CD4 communicate with other cells by secreting lymphokines and interleukins, host of HIV 2. T-killer cells: CD8, cytotoxic T cells ---destroy virus-infected host cells ---destroy cancer cells ---destroy foreign cells **The protein on T cell surface that can bind antigen is T-cell receptor ** T cell recognized cell surface proteins: MHC I and MHCII * MHCI is found on the surface of every nucleated cell, they randomly pick up proteins inside the cell and display them * MHC II only present in APC (antigen-presenting cells)such as macrophages and B cells. They display MHC II on the surface and is recognized by T helper cells and after Helper cells are activated by antigen displayed in MHCII, it will activate B cells and stimulate proliferation of T killer cells that are specific for that antigen. The activated B cells mature into plasma and memory and secrete antibodies specific for the antigen *Full activation of T cells only occurs when T cells bind to both antigen displayed on MHC I or II and MHC itself

stomach

1. The zymogen (inactive) pepsinogen is released by gastric chief cells and is converted into pepsin (active form) on mixing with (HCl) in the gastric juice. Pepsin then digests proteins in the stomach. 2. Gastrin, a peptide hormone released by gastric G cells, stimulates HCl secretion from parietal cells in the stomach and promotes stomach churning to assist gastric motility. 3. The stomach normally protects itself from autodigestion by HCl and proteolytic enzymes in the gastric juice. Mucus is released by mucous cells in the stomach to form a protective physical barrier against autodigestion. Bicarbonate ions are released from stomach epithelial cells form a chemical buffer barrier under the mucus barrier

¨ Intestinal Villus: 3 important structures

1. Villus contain capillaries absorb monosaccharide and aa. They merge into veins hepatic portal vein transport blood containing nutrients from gut to liver 2. Lacteals: contains small lymphatic vessels to absorb dietary fats 3. Peyer's patches: collections of lymphocytes immune

Exchange of substances across intercellular clefts in the capillary walls

1. aa and glucose absorbed from digestive tract and carried by hepatic portal vein 2. Lipids are absorbed from intestine and packed into chylomicrons, then enter lymphatic vessels in intestinal wall called lacteals, then into lymphatics -> then drain into the large vein in neck. Chylomicrons are then converted into other types of lipoproteins and stored in liver 3. WBC: only macrophages and neutrophils can squeeze through clefts by amoeboid motility 4. Water has great tendency to flow out of capillaries, therefore, albumin keeps water in capillaries

Sympathetic nervous system: regulate heart during fight or flight

1. sympathetic postganglionic neurons directly innervate the heart, releasing norepinephrine 2. epinephrine secreted by adrenal medulla bind to receptor on cardiac muscle cells -> HR increases

When (ACh) is released by the motor neuron at the neuromuscular junction, the following occur:

1.ACh binds and opens ligand-gated ion channels in the sarcolemma (the plasma membrane of the muscle cell) 2.Na+ flows down its electrochemical gradient and into the cell through the channel, resulting in depolarization of the sarcolemma and generation of an action potential that propagates along the muscle fiber in all directions. At certain locations along the muscle fiber, the sarcolemma burrows deep into the cells, forming a channel known as the transverse (T) tubule, which brings depolarizing current close to the sarcoplasmic reticulum (SR). 3. The SR is a specialized smooth endoplasmic reticulum responsible for regulating cytosolic Ca2+ levels within the muscle cell. 4. Action potential propagation through the T tubule ultimately leads to the opening of Ca2+ channels in the SR membrane. Because Ca2+ is more highly concentrated inside the SR than in the cytosol, the opening of these channels results in Ca2+ flowing down its concentration gradient and into the cytosol. 5. Cytosolic Ca2+ ions then bind to troponin, which allows the actin and myosin filaments of the sarcomere to slide across one another. The sliding of the filaments results in shortening of the sarcomere and overall muscle contraction. 6. The Ca2+ channels in the SR membrane close when the depolarizing stimulus ceases. Active transport Ca2+ pumps sequester the Ca2+ back into the SR, which allows the muscle to return to its relaxed state as cytosolic Ca2+ concentration falls.

Normal tissue that has been damaged is replaced by scar tissue, which is made primarily of collagen-producing cells (fibroblasts). What normal skin functions are affected?

1.Protection from ultraviolet (UV) radiation: Melanin, a dark pigment produced by epidermal melanocytes, absorbs and prevents UV light from damaging the DNA. Melanin is transferred from the melanocytes to the keratinocytes, cells that produce the structural protein keratin. The lack of melanocytes in the scar tissue would reduce the affected area's resistance to the harmful effects of UV radiation 2.Hair growth: Hair strands are composed of dead keratinized cells and are produced in the hair follicles, structures that contain both epidermal and dermal components. Therefore, scarring that replaces the epidermis and dermis would impair hair growth. Fingernails, toenails, and calluses are also protective keratinized structures derived from the skin. 3.Sweating: Sweat glands arise from the dermis and secrete sweat through ducts in the epidermis. Because scar tissue does not contain sweat glands, the scarred area would be incapable of salt excretion

Nephron Anatomy

1.Proximal tubule: In this segment, important nutrients (eg, amino acids, vitamins, salts, glucose, water) are reabsorbed from the nephron and incorporated back into the blood through the peritubular capillaries that surround the tubule. Waste products not filtered by Bowman's capsule are actively secreted from the peritubular capillaries into the nephron. 2.The loop of Henle: This segment is a hairpin structure composed of two limbs. The descending limb extends down into the relatively salty medulla (inner portion of the kidney) and is permeable to water, allowing the passive reabsorption of water via osmosis. The ascending limb transports filtrate out of the medulla and back to the cortex (outer portion of the kidney). This limb is permeable to salt but impermeable to water; this leads to active reabsorption of ions only, which concentrates the medullary interstitial fluid (maintains its saltiness) and prevents its dilution. 3.Distal tubule: Antidiuretic hormone (ADH; vasopressin) and aldosterone promote the reabsorption of water in this segment of the tubule. Additional waste products are secreted into the nephron from the peritubular capillaries. 4.Collecting duct: ADH and aldosterone act on the collecting duct in the same way they act on the distal tubule. The now-concentrated urine is emptied into the ureters for excretion.

cranial nerves

12 pairs of nerves that carry messages to and from the brainstem

Symbiotic bacteria

live mutually with hosts, such as rhizobia and cyanobacteria fixing nitrogen for plants, have smaller genomes

3 compartments contain erectile tissue:

2 corpora cavernosa and 1 corpus spongiosum

The scrotum contains the testes and spermatic cords

2 functions: spermatogenesis and secretion of male sex hormones

hermorrhage

loss of blood

· Pleiotropism:

A gene's expression alters many different phenotype

Proteasomes

A giant protein complex that recognizes and destroys proteins tagged for elimination by the small protein ubiquitin. contains protease

Haplotype

A group of alleles of different genes on a single chromosome that are closely enough linked to be inherited usually as a unit

Tissues that are exposed to the external environment have mucosal membranes.

A mucous membrane or mucosa is a membrane that lines various cavities in the body and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue.

kinetochore

A specialized region on the centromere that links each sister chromatid to the mitotic spindle.

RT-PCR

A technique in which RNA is first converted to cDNA by the use of the enzyme reverse transcriptase, then the cDNA is amplified by the polymerase chain reaction. measures mRNA level

· Epistasis:

A type of gene interaction in which one gene alters the phenotypic effects of another gene that is independently inherited.

Neutrophils

A type of white blood cell that engulfs invading microbes and contributes to the nonspecific defenses of the body against disease.

acrosome

A vesicle at the tip of a sperm cell that helps the sperm penetrate the egg

primary active transport

Active transport that relies directly on the hydrolysis of ATP. ex: Na K ATP pump

DNA polymerase

Adds nucleotides to the growing strand. It reads the template 3' to 5' and synthesize the new strand 5' to 3'. DNA Polymerase also removes the RNA primer at the end of the strand.

Connective tissue

Adipose tissue bone blood cartilage (chondrocyte) ligament

X-linked recessive

Affected males have asymptomatic carrier mothers in X-linked recessive conditions, which are inherited via the X chromosome. Two mutant alleles must be inherited to cause disease in females (XX), but only one mutant allele is required to cause the disease in males (XY).

Leptin

After a meal, the body is in an energy-rich state (ie, high concentrations of glucose and lipids); as a result, the hormone leptin is released by white adipose tissue to trigger feelings of satiety by communicating to the hypothalamus in the brain that the stomach is full, thereby suppressing appetite. In general, the greater the adipose tissue stores, the higher the leptin levels in the serum.

Oogenesis is the process by which females produce sex cells (gametes) called eggs

All of a woman's developing eggs (oocytes) are produced during fetal development. At birth, their maturation is arrested in prophase I; these arrested eggs are known as primary oocytes. At puberty, the menstrual cycle begins, and each month a single primary oocyte develops into a secondary oocyte by continuing meiosis up to metaphase II. During the follicular phase of the cycle, the follicle (oocyte plus supporting granulosa cells) matures until it bulges at the outer wall of the ovary. Maturation and growth of the follicle is driven by the release of follicle-stimulating hormone (FSH) from the anterior pituitary. A subsequent release of luteinizing hormone (LH) stimulates follicle rupture and the release of the secondary oocyte near the opening of the fallopian tube (ovulation).

Henry's Law equation

Amt of gas dissolved into liquid =partial pressure of the gas * solubility of the gas in liquid pressure increase, increase gas dissolved § Gas becomes less soluble when temperature increases

amino acid activation =tRNA loading

An aa is attached to an ATP to form aminoacyl AMP--> Attachment of amino acid to tRNA. Catalyzed by aminoacyl- tRNA synthetases.

DNA helicase

An enzyme that unwinds the DNA double helix during DNA replication

opsonization

An immune response in which the binding of antibodies to the surface of a microbe facilitates phagocytosis of the the microbe by a macrophage

zymogen

An inactive precursor of an enzyme, activated by various methods (acid hydrolysis, cleavage by another enzyme, etc.)

Cerebellum

Balance and coordination

Inflation of lungs in mammals is accomplished by negative pressure pumping action.

Because the lung stays in contact with the thoracic wall as it enlarges due to contraction of the diaphragm and the external intercostal muscles, a pressure that is lower than atmospheric pressure (negative pressure) is generated within the alveolar sacs.

Tendons

Connect muscle to bone

ligament

Connects bone to bone

DNA polymerase II

DNA polymerase II digests away the RNA primer and replaces the RNA nucleotides of the primer with the proper DNA nucleotides to fill the gap

pressure gradient from arterial system to venous system results from blood flow times peripheral resistance

Delta P=Q x R

surfactant

During inspiration, contraction of the diaphragm and external intercostal muscles leads to expansion of the thoracic cavity and a decrease in intrapleural pressure. This negative pressure, relative to atmospheric pressure at the entry of the upper airway, generates airflow through the respiratory tree and to its terminal extension—the alveoli. The elastic recoil force of the airway and the surface tension of the water lining the airway oppose expansion of the alveoli due to the influx of atmospheric pressure. Pulmonary surfactant adsorbed to the air-water-alveoli interface, reducing surface tension and the total force resisting expansion. This increases pulmonary compliance—a measure of lung volume change at a given pressure of inspired air—and decreases the work required to expand the lungs at a given atmospheric pressure. In general, surfactant molecules are amphipathic, meaning that they contain both hydrophobic and hydrophilic regions.

Gastric juice

Gastric juice is a digestive fluid primarily composed of (HCl), which is secreted by parietal cells in the stomach. pH of 1-3->required for protein digestion (via activation of proteolytic enzymes) and for killing harmful bacteria. After sufficient churning, the stomach expels a semifluid mass of partially digested food mixed with gastric juice, known as chyme. The highly acidic chyme passes into the duodenum, where it is neutralized by the bicarbonate ions secreted from the pancreas via the pancreatic duct and the alkaline bile released from storage in the gallbladder. As a result, the pH of the chyme is increased to ~6.

Post-implantation Development

Gastrulation · Blastulation -> gastrulation=when 3 primary germ layers (ectoderm, mesoderm, endoderm) becomes distinct. · During gastrulation, the archenteron develops into the digestive tube, with the blastopore developing into either the mouth (protostome) or the anus (deuterostome). Human: Whole structure is gastrula, develops from embryonic disk. · Ectoderm: Nervous system, pituitary glands, adrenal medulla, cornea and lens, skin, hair, nails, mouth, anus. "Atracto": Skin, hair are things people are attracted to. · Mesoderm: Musco skeleton, muscle, bone, connective tissue, lymphatic system, dermis of skins, circulatory system, gonads, ureters, kidneys, reproductive ducts, adrenal cortex. "Move": Involved in moving things such as muscles, RBC, steroids. Endoderm: Endocrine glands, GI tract, liver, pancreas, respiratory tract, bronchi, bladder, stomach. "Indo": Things that are inside.

3 germ layers

Gastrulation is the process by which the germ layers (endoderm, mesoderm, ectoderm) form in the developing embryo. Following fertilization, the zygote undergoes cleavage (successive mitotic cell divisions) and forms blastocyst The two-layered blastocyst then transforms into a three-layered structure (gastrula) through the process of gastrulation. Cells migrate through the primitive streak and the area between the two layers to displace the bottom (hypoblast) layer and form the endoderm. Additional cells migrate through the streak to form the new middle layer (mesoderm). All three germ layers develop into specific structures within the human body as follows: Endoderm (innermost layer): gives rise to accessory digestive organs (eg, liver, pancreas) as well as to the lining (epithelium) of the digestive and respiratory tracts. Mesoderm (middle layer): gives rise to the circulatory system, the musculoskeletal system, and parts of the urinary and reproductive systems. Ectoderm (outermost layer): gives rise to the nervous system (neurulation) and develops into the integumentary system, which includes hair, skin, nails, and the lining of the mouth, nostrils, and anus.

imprinted genes

Genes that are expressed either the maternal or paternal. sexes can inherit the mutated gene from either the father or the mother and will have the same genotype

thymus

Gland in the thoracic cavity above the heart where T lymphocytes mature.

Fermentation

Glucose catabolism that doesn't use electron acceptor such as O2. A reduced by-product of glucose catabolism such as lactate or ethanol produced

PAGE vs. SDS PAGE electrophoresis vs REDUCING SDS PAGE

PAGE: for DNA, top: negative cathode, bottom:+ anode longer DNA at top SDS PAGE: FOR protein by weight Reducing page: break disulfide bond, break dimers

menstral cycle

I. Ovarian Cycle 1. follicular phase: 13 days. A primary follicle matures and secretes estrogen. Maturation of the follicle is under the control of follicle stimulating hormone FSH from anterior pituitary. 2. Ovulatory Phase: On day 14. A secondary oocyte is released form ovary. Triggered by luteinizing hormone LH from anterior pituitary. LH also causes remnant of follicle to become corpus luteum. 3. Luteal Phase: 14 days. Begin with full formation of corpus luteum in the ovary. It secretes both estrogen and progesterone. II. Uterine Cycle 1. Menstruation 5 days. Triggered by degeneration of corpus luteum and the drop level of E and P hormones. ->causes previous cycle's endometrial(子宫内膜) lining to slough out of uterus -> bleeding 2. Proliferative phase: 9 days. Estrogen produced by follicle induces the proliferation of a new endometrium. 3. Secretory phase: 14 days. E and P produced by corpus luteum further increase the development of endometrium->secretion of glycogen, lipids. If pregnancy don't occur ->death of corpus ->another menstruation

imprinted genes vs sex linked

Imprinted genes should not be confused with sex-linked genes, which are carried on the X or Y chromosome. Most imprinted alleles are located on autosomes, but are "stamped" with the sex of the parent that contributed them.

ELISA

In ELISA, samples are first added to a 96-well microplate, and the antigens (eg, proteins) become adsorbed (immobilized) to the surface of the well. A specific primary antibody linked to a "reporter" enzyme is then added to bind the antigen. The samples are washed to remove unbound antibodies, and the substrate of the reporter enzyme is added. The enzyme reacts with its substrate to generate ("report") a colored product, and if a color change is detected, its intensity is proportional to the amount of bound protein. Protein expression levels are ultimately quantified by comparing the color change in the well plate to the color change observed from a series of known concentration standards.

Meiosis

In eukaryotic organisms, gametes (eggs, sperm) form via meiosis, a process of cellular division resulting in the production of four haploid (1N) daughter cells from a single diploid (2N) parental cell. Meiosis occurs in two stages, meiosis I and meiosis II, each of which is composed of prophase, metaphase, anaphase, and telophase followed by cytokinesis (cell division): Meiosis I: In prophase I, the nuclear envelope of a diploid parental cell disintegrates and homologous chromosomes (each consisting of two sister chromatids) pair up. In the phase that follows (metaphase I), these chromosomes align in the middle of the cell (ie, at the metaphase plate). The chromosomes are pulled to opposite poles of the cell by the meiotic spindle in anaphase I. The nuclear envelope then reforms in telophase I and the cytoplasm of the cell divides (cytokinesis) to yield two haploid daughter cells. Meiosis II: A process similar to meiosis I occurs in this stage, with the exception that it occurs in the previously formed haploid daughter cells. Following nuclear envelope disintegration in prophase II, chromosomes align at the metaphase plate during metaphase II. However, in anaphase II sister chromatids (not homologous chromosomes) are pulled to opposite poles of the cell by the meiotic spindle. Reformation of the nuclear envelope in telophase II and cell division (cytokinesis) of each cell yields four haploid daughter cells.

nondisjunction refers to the failure of chromosomes or chromatids to properly separate during anaphase. Nondisjunction can occur during meiosis I or meiosis II.

In the diagram below, the left image shows nondisjunction during meiosis II, while the right-hand image shows the same event occurring during meiosis I.

spatial summation

Integration by a postsynaptic neuron of inputs (EPSPs and IPSPs) from multiple sources.

mucociliary escalator

Layer of mucus moved by cilia of columnar epithelial cells lining the respiratory tract that traps bacteria and other particles and moves them into the throat

Hypoxia

Low oxygen saturation of the body, not enough oxygen in the blood---->increase in heart rate and breathing rate

lub vs dub

Lub from closure of AV valves at the beginning of systole. Dup is the sound of closing semilunar at the end of systole

hemophilia

Like to bleed

Antagonistic

Muscle that are responsible for movement in opposite directions -flexor and extensor

synergistic

Muscle that are responsible for movement in same direction

The Neuromuscular junction and impulse transmission

Neuromuscular junction (NMJ) is the synapse between axon terminus and a myofiber. The NMJ is a long infolding of the cell membrane àallow neuron to depolarize a large portion of postsynaptic membrane at once. The postsynaptic membrane (myofiber cell membrane) =motor end plate. ACh is the neurotransmitter. Impulse transmission at NMJ is chemical synaptic transmission. AP arrives at axon terminus, cause the opening of Ca2+ channels, the resulting increase in intracellular Ca2+ causes the release of ACh vesicles. àThe postsynaptic membrane has Ca2+ receptors, which is ligand gated Na+ channel. Binding of Ca2+àinflux of Na+àdepolarization of postsynaptic membrane. àend plate potential (EPP)

Platelets

NO nuclei, limited life span, derived from megakaryocytes (bone marrow) Function is to form platelet plug and prevent bleeding (Hemostasis)

Neurulation

Neurulation is the formation of the nervous system in vertebrate organisms. Following gastrulation (formation of the three germ layers), the notochord, a mesodermal cylindrical structure, releases signals promoting the ectoderm above to thicken and form the neural plate. The neural plate folds inward, forming the neural groove, and the edges of the plate (the neural folds) converge to create the neural tube. The neural tube, which is the precursor of the central nervous system, then pinches off the ectoderm. The remaining sections of the neural folds not included in the neural tube comprise the neural crest. Neural crest cells migrate away from the tube and toward the periphery of the embryo to give rise to most of the peripheral nervous system (PNS). Note that although somatic motor neurons are part of the PNS, their cell bodies originate in the CNS.

Termination

Occurs when the codon in the A site is a stop codon; release factor places a water molecule on the polypeptide chain and thus releases the protein.

airflow pathway

Oral/Nasal cavity Pharynx epiglottis Larynx Trachea Primary Bronchi Secondary Bronchi Tertiary Bronchi Bronchioles Terminal Bronchioles Alveoli are sacs coated with surfactant, a film that reduces surface tension, allowing the alveoli to remain inflated when the lung is compressed during exhalation. Lungs

Cells can conduct endocytosis through three major mechanisms: phagocytosis, pinocytosis, and receptor-mediated endocytosis.

Phagocytosis, = cells engulf external particles by extending portions of their membrane to reach around the particle rather than by the inward budding of the membrane Pinocytosis is a nonspecific process (ie, does not require receptor binding) that involves the continuous invagination of the cell membrane to take up extracellular fluid. --Viruses with a capsid encased in a phospholipid membrane, known as enveloped viruses, can fuse their membranes with the cell membrane. When this occurs, no vesicle is formed and the capsid is released directly into the cytosol.

endochondral ossification

Process of transforming cartilage into bone. -During fetal development, hyaline cartilage composing the fetal skeleton is replaced by bone (ie, it calcifies). In children and adolescents, the epiphyseal (growth) plate of long bones is formed from hyaline cartilage and serves as the site of bone lengthening.

Translation: Initiation

Prokaryotes: When the 30S ribosome and binds to 2 initiation proteins IF1 and IF3 attaches to the Shine-Delgarno Sequence and scans for a start codon; it lays down N-fMet-tRNA in the P site of the ribosome. Eukaryotes: When the 40S ribosome attaches to the 5' cap and scans for a start codon; it lays down methionine in the P site of the ribosome.--No shine-Dalgarno sequence to initiate translation

Mitosis: prophase, metaphase, anaphase, telophase

Prophase: DNA condenses to form chromatids. Each pair of sister (identical) chromatids are joined by a region called the centromere to form chromosomes. The nuclear envelope breaks down and centrosomes (microtubule-organizing structures) migrate to opposite poles within the cell. The mitotic spindle is formed as microtubules grow from these centrosomes. Metaphase: Chromosomes attach to spindle fiber microtubules at their kinetochores and align at the metaphase plate, a central plane within the cell. Anaphase: Sister chromatids are pulled apart by the spindle fibers and move toward opposite poles of the cell. This forms two sets of chromosomes within the cell (one set at each cellular pole). Telophase: The nuclear envelope is reformed around each set of chromosomes. Chromosomes decondense and the parental cell undergoes cytokinesis (cytoplasmic division) to produce two identical daughter cells.

Hydrolase

Protease is hydrolase

Constitutive secretory pathway

Proteins sent in vesicles from Golgi immediately to cell surface, not regulated

protein secretory pathway

Proteins that are embedded in the plasma membrane traveled through the secretory pathway to arrive there. proteins intended for the secretory pathway have an N-terminal sequence called a signal sequence. Once the signal sequence is recognized, the ribosome is transported to the (RER) In the RER, some post-translational modifications may occur, including glycosylation, disulfide bond formation, phosphorylation, and protein cleavage. The RER then packages proteins into vesicles and sends them to the Golgi apparatus, where they are further processed. Finally, the Golgi packages proteins destined for the plasma membrane into secretory vesicles, which fuse with the plasma membrane.

The respiratory tract can be divided into the conducting zone(participate only in ventilation) and the respiratory zone.

The conducting zone includes the nose, pharynx, larynx (voice box), trachea (windpipe), bronchi, and terminal bronchioles.

tRNA is produced by

RNA polymerase III

Blood types

RR Rr are Rh positive --rr is Rh negative ---Sensitization: antibodies to Rh antigen developed when Rh- is exposed to Rh+ --Especially dangerous when Rh- mother carrying Rh+ baby and their blood mixed. --Future Rh+ babies will be in risk (hemolytic disease of new born=erythroblastosis fetalis) bc anti-Rh antibodies can cross placenta and destroy Rh+ babies' blood cells. ->inject mother with anti-Rh antibodies at time of birth can prevent sensitization --AB+ can receive any type of blood bc they possess all 3 kinds of antigens --O- can donate to any type bc they have none of the 3 kinds of antigens

SEVENUP (Seminiferous tubules, Epididymis, Vas deferens, Ejaculatory duct, nothing, Urethra, Penis)

Seminiferous tubules empty into epididymis empty into ductus deferens then enters inguinal canal ->enters pelvic cavity ->duct of seminal vesicle ->form ejaculatory duct then leads to urethra

Repolarization

Return of the cell to resting state: Na voltage gated ion channel close when its +35mV. Then K+ channels are opened, K+ flow out of cells -->make the potential -90mV then voltage gated K+ channels are closed.

AP path in heart

SA node ->internodal tract->AV node->delayed, then to ventricles (AV bundle, bundle of His)->left and right bundles ->purkinje fibers (spread over the inferior of ventricle)

Functions of glial cells in the PNS include:

Schwann cells wrap the axons of some neurons with myelin to increase conduction speed. Satellite cells provide structural support and supply nutrients to neuron cell bodies in sensory, sympathetic, and parasympathetic ganglia (groups of cell bodies). similar to astrocytes in the CNS

spermatogenesis

Spermatogenesis occurs in the seminiferous tubules of the testes (the male gonads). The outer fibrous capsule of the testes encloses the seminiferous tubules, which are coiled and divided into numerous compartments. A cross-section of these tubules shows that they contain developing sperm cells and "nurse cells" known as Sertoli cells, which provide nourishment to sperm and regulate their development. In addition, the interstitial tissue of a seminiferous tubule houses Leydig cells, which secrete testosterone in response to LH release from the anterior pituitary and stimulate sperm cell differentiation. Spermatogonia, stem cells that undergo cell division to become mature sperm, appear near the basement membrane of the seminiferous tubule. Spermatogonia first divide by mitosis to yield two daughter cells, one of which becomes a spermatocyte upon beginning meiosis I. Spermatocytes subsequently become spermatids upon completion of meiosis II. Spermatids then become spermatozoa (mature sperm) through loss of most of their cytoplasm, acrosome formation around the nucleus, mitochondrial concentration around the midpiece, and development of a tail (flagellum). The spermatozoa that result are small, nonmotile gametes that bear little resemblance to the original spermatogonia. As sperm develop, they are transferred from the basement membrane and released into the lumen of the seminiferous tubules. Following this, sperm exit the testes and are carried to the epididymis, where they become motile and are stored.

homologous structures

Structures in different species that are similar because of common ancestry.

temporal summation

Summation by a postsynaptic cell of input (EPSPs or IPSPs) from a single source over time.

Blow flow through the heart

Superior/inferior vena cava+coronary sinus > right atrium > tricuspid valve > right ventricle > pulmonic valve > pulmonary artery > lungs > pulmonary veins > left atrium > mitral valve > left ventricle > aortic valve > body (systemic circulation)

3 functional classifications of joints

Synarthroses (immovable joints) amphiarthroses=slightly movable joints diarthroses=freely

During replication, DNA polymerase attaches uncoupled deoxyribonucleoside triphosphates (dNTPs) to the growing DNA strand. Each dNTP (dTTP, dATP, dCTP, and dGTP) is composed of a base, a deoxyribose sugar, and three phosphate (PO4) groups.

The 3′ OH from the last nucleotide of the new growing strand "attacks" the 5′ PO4 group of the incoming dNTP. As a result, two phosphate groups are cleaved off the dNTP, resulting in a nucleoside monophosphate molecule and in the release of water, pyrophosphate (PPi), and energy (exergonic process). PPi is further cleaved into two phosphate groups to release more energy. The energy generated from these reactions is used to form a covalent phosphodiester bond between the last nucleotide of the growing strand and the incoming dNTP (endergonic process). Once the phosphodiester bond is formed, the enzyme proceeds to couple the next free dNTP to the new growing strand.

adapted immunity

The adaptive immune response is further subdivided into cell-mediated immunity and humoral immunity. Humoral immunity, specifically, is driven by B lymphocytes that secrete antibodies, specialized proteins that recognize specific foreign antigens (ie, molecules targeted by the immune system). These antibodies circulate throughout the blood and lymph, binding foreign antigens and marking them for destruction by other immune cells. A mature B lymphocyte is inactive until its receptors bind a specific foreign antigen. On activation by antigen binding, the B lymphocyte endocytoses (engulfs) the antigen, breaking it down into smaller fragments. Within the B lymphocyte, specialized antigen-binding molecules called major histocompatibility class II (MHC II) proteins bind the antigen fragments. MHC-antigen complexes are transported to the surface of the B lymphocyte and integrate into the cell membrane, allowing antigen fragments to be displayed outside the cell and presented to other immune cells known as helper T cells. On binding antigens presented by B lymphocytes, helper T cells release cytokines (signaling molecules) that stimulate B-lymphocyte proliferation. This produces many identical B lymphocytes that may differentiate into either of the following cell types: 1.Short-lived plasma cells secrete antibodies during the immediate immune response. 2.Long-lived memory cells remain in lymphoid tissues for a long time and can recognize the antigen more rapidly in the event of a future infection

adrenal cortex hormones

The adrenal cortex secretes the hormones cortisol and aldosterone, and the adrenal medulla secretes the hormones epinephrine and norepinephrine. 1.Aldosterone, secreted from the adrenal cortex, stimulates Na+ reabsorption in the kidneys, leading to increased water retention due to osmosis. Increased water retention increases blood volume, which in turn leads to an increase in blood pressure. 2.Norepinephrine and epinephrine, secreted from the adrenal medulla, function to mobilize the body under extreme stress and promote rapid information processing in part by maximizing blood flow to organs essential for survival. Norepinephrine and epinephrine achieve this effect by promoting the following changes in blood vessel diameter that lead to altered blood pressure: Vasoconstriction (narrowing) of blood vessels supplying the intestines, kidney, and other abdominal organs decreases blood flow to these organs and conserves oxygen/nutrients for other tissues. Vasodilation (widening) of blood vessels leading to the heart and skeletal muscles increases oxygen/nutrient delivery to these organs.

morula to blastula to gastrula to neurulation.

The blastocoel is a fluid-filled central region present in the blastocyst during mammalian embryogenesis. The blastocyst consists of an inner cell mass (ICM), along with an outer cell layer called the trophoblast, which surrounds both the ICM and blastocoel.

macula densa

The cells of the distal tubule at the juxtaglomerular apparatus. They are receptors that monitor filtrate osmolarity in distal tubule as a means of regulating filtration rate. If a drop is osmolarity is sensed=reduced filtration rate, the macula densa dilates the afferent arteriole (to increase the blood pressure in the glomerulus and thus increase filtration) and stimulates the juxtaglomerular cells to secrete renin (to raise systemic blood pressure).

anterior lobe of the pituitary gland

The hypothalamus controls the anterior lobe of the pituitary gland by releasing signaling molecules into the hypophyseal portal system corticotrophin-releasing hormone (CRH) released by the hypothalamus stimulates the anterior pituitary to release adrenocorticotropic hormone (ACTH) into the systemic circulation. ACTH then acts on the adrenal glands to promote synthesis and secretion of glucocorticoids, completing the neuroendocrine pathway that regulates the serum level of cortisol and other glucocorticoids

size of organisms

The limit of resolution of a light microscope is about 200 nm. The virions are around 100nm.

lymphatic system

The lymphatic system is a network of vessels that collect and transport lymph, ultimately draining this fluid into the bloodstream. 1. Bone marrow, a spongy tissue lining the inside of bones, is responsible for the production of red blood cells and white blood cells (eg, lymphocytes) from hematopoietic stem cells. 2. Thymus receives immature T lymphocytes migrating from the bone marrow and facilitates their maturation. During this process, any T lymphocytes that recognize self-antigens die, preventing the release of lymphocytes able to mount attacks against the body's own tissues. However, T lymphocytes that do not bind self-antigens mature and enter the blood and lymph, where they bind foreign antigens and mount immune responses. 3. Lymph nodes, organs clustered along lymph vessels, filter lymph as it flows through the lymphatic system. Macrophages housed within lymph nodes identify a variety of pathogens in lymph and destroy them via phagocytosis. In addition, B lymphocytes and T lymphocytes bind specific foreign antigens in lymph, inducing immune responses against invading pathogens. 4. Spleen has extensive capillary networks through which blood is filtered. White blood cells housed within the spleen recognize and bind foreign antigens in the blood, mounting immune responses against these circulating pathogens. In addition, spleen macrophages remove and destroy old and damaged red blood cells. Platelets and other white blood cells are also stored in the spleen and released into the blood as needed.

enteric nervous system ANS

The nervous system of the gastrointestinal tract. It controls secretion and motility within teh Gi tract, and is linked to the central nervous system. 1. myenteric plexus: regulate gut motility 2. submucosal plexus: in submucosa, regulate gut blood flow, enzyme secretion, ion/water balance

Template/non-coding/antisense strand

The strand that is transcribed, The other strand is called coding or sense strand, has same sequence as the transcript except for the T

trp operon

The trp operon is a group of genes that encode biosynthetic enzymes for tryptophan. The trp operon is expressed when tryptophan levels are low and repressed when they are high. The trp operon is regulated by the trp repressor. When trp is not present, nothing binds to repressor, repressor cant bind to operator

Repressible Systems

Transcribed under normal conditions; they can be turned off by a corepressor coupling with the repressor and the binding of this complex to the operator site. Example: Trp operon

transition vs transversion mutation

Transition- a purine is converted into a purine or pyrimidine is converted into a pyrimidine. Transversion: a purine is converted into a pyrimidine (or vice versa)

DNA translation

Translation, the energy-requiring process by which ribosomes (with E, P, and A sites) make proteins from mRNA, occurs in eukaryotes in the following stages: 1. Initiation: The small 40S ribosomal subunit complexes with initiation factors and binds the mRNA 5′ cap to scan the mRNA for the start codon (5'-AUG-3'), which codes for the amino acid methionine. An initiator transfer RNA (tRNA) molecule "charged" with methionine contains a complementary anticodon (3'-UAC-5') that base pairs with the AUG codon on mRNA Subsequently, the 60S subunit is recruited and binds the initiator tRNA at the P site, marking the formation of the translation complex. 2. Elongation: The ribosome continues to elongate the polypeptide chain by reading each mRNA codon in a 5′ to 3′ direction. During this step, a new charged tRNA with a complementary anticodon enters the A site. The enzyme peptidyl transferase then transfers the growing polypeptide chain from the tRNA at the P site to the new tRNA at the A site by catalyzing the peptide bond between adjacent amino acids on these tRNAs. The ribosome moves one codon forward, allowing the uncharged tRNA at the P site to translocate to the E site, where it is ejected. Another charged tRNA enters the A site, and this process is repeated until the ribosome encounters a stop codon. 3. Termination: The polypeptide is released from ribosomes when a stop codon (UAA, UAG, or UGA) is detected in the mRNA at the A site, indicating the end of translation. Release factors induce peptidyl transferase to cleave the ester (not peptide) bond between the polypeptide and the final tRNA, causing disassociation of the translation complex.

covergent evolution

Unrelated species evolve similar traits

Lysosomes

Uses chemicals to break down food and worn out cell parts

Variable expressivity vs. penetrance

Variable expressivity =ability of a single genotype to give rise to multiple phenotypes. Penetrance =proportion of individuals with a genotype who express the corresponding phenotype. When every individual with a specific genotype displays the associated phenotype, the allele is said to show complete penetrance. When all individuals have the same genotype but only some express the corresponding phenotype, the disease is said to show incomplete penetrance

genomic imprinting

Variation in phenotype depending on whether an allele is inherited from the male or female parent. Only one allele of the gene is expressed

Totipotent stem cells, which are found only in the zygote and up to the eight-cell stage of its mitotic division, have the greatest potency as they alone can autonomously give rise to an entire organism. Consequently, totipotent cells can differentiate into any cell type from either an embryonic or extraembryonic (placental) lineage. Following the eight-cell stage, the blastocyst forms. This hollow structure contains an outer cell layer (trophoblast), which forms the placenta, and an inner cell mass, which forms the embryo. The cells of the inner cell mass are said to be pluripotent as these are able to differentiate into any cell found in the body. Pluripotent cells can give rise to any of the three primary germ layers found in the embryo but not the cells found in placental structures. Therefore, pluripotent cells are more specialized (differentiated) than totipotent cells. multipotent can differentiate into cells with many specialized functions but are limited in that they are "committed" to a specific lineage. For example, multipotent neural stem cells can give rise to the various cells of nervous tissue but cannot give rise to cells found in other tissue types.

Very primitive cells =totipotent cells "Total", can be any type of cell Pluripotent: Can be any cell except those found in placental structures Multipotent: More specialized. Can be multiple types of cells Dedifferentiation: specialized cells becomes toti again cancer

Depolarization

Voltage gated Na+ channel in plasma membrane of axon is opened by depolarization of membrane from resting potential to -50mV. During the action potential, the channels will open and sodium is rushing into the cell causing the interior to become more positive.

Eosinophils

WBC for asthma and parasitic infections, allergies

Hindbrain

medulla, pons, cerebellum

RNA Interference:

a way to silence gene expression after a transcript has been made -> mediated by miRNA and siRNA. siRNA bind to mRNA and this dsRNA is degraded

A sarcomere shortens when

Z line and M line pulled closer to each other

upstream control elements (UCE)

a core promoter containing binding sites for the basal transcription complex RNA polymerase II and a TATA box which binds to TATA box binding protein (TBP) which initiates transcription complex assembly at promoter.

negative control

a group of data lacking what is being tested so as to give expected negative results

Hypothalamus

a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion, homeostasis , hormone release, appetite, fluid balance --controls primitive emo such as anger sex drive

RNA Primers

a short strand of RNA, made by DNA primase, that is used to elongate a strand of DNA during DNA replication

Non-sense mutation

a stop codon is added instead of amino acid

· Polygenism:

a trait influenced by many genes

Chemical synapse: ends of axons, AP are converted to chemicals

a. AP reaches the terminal of axon, the synaptic knob b. Depolarization causes voltage gated Ca2+ to open c. Causes Ca2+ influx into presynaptic cells -> exocytosis of neurotransmitters stored in secretory vesicles d. Neurotransmitters released and cross synaptic cleft, binds to receptor on postsynaptic membrane. These receptors are ligand gated ion channels e. Opening of the channels can cause depolarization -> if reaches threshold -> voltage gated Na+ channel will open -> AP initiated f. Neurotransmitters in the synaptic cleft are degraded or removed to terminate the signal EX: neuromuscular junction between neurons and skeletal muscle

innate immunity

a. Skin b. Tears, saliva, blood contains lysozyme which kill some bacteria by destroying their cell wall c. Acidity of stomach destroys many pathogens d. Macrophages and neutrophils phagocytize microorganism Complement system: group of 20 blood proteins that nonspecifically bind

calcium triggers the binding of myosin to actin

a. When Ca is added, tropomyosin moves relative to actin within thin filament b. Along tropomyosin cables, there are troponin (act like regulatory factor to produce shift of position of tropomyosin cables) c. Absence of Ca, tropomyosin line along a position that blocks myosin binding site on actin sub U -> no contraction d. With Ca, troponin bind to Ca ->pushes tropomyosin to a new position->expose tropomyosin binding sites on actin filaments->form cross bridges b/w thin and thick ->regulated by sarcoplasmic reticulum(organelle that contains high conc of Ca, also have transporters in membrane ->allows transfer of Ca e. When brain sends signal->sarcoplasmic reticulum releases Ca->shift of position of cable->expose myosin binding site->contraction f. No longer contract->pumps Ca back into organelle->troponin releases Ca->tropomyosin blocks binding site ->no contract

Inner cell mass also produce

amnion(membrane covers the embryo with fluid), yolk sac(first site of RBC synthesis), allantois(forms blood vessels of umbilical cord which transport blood bw embryo and placenta.

clonal selection

an antigen selectively binds to and activates only those lymphocytes bearing receptors specific for the antigen. The selected lymphocytes proliferate and differentiate into a clone of effector cells and a clone of memory cells specific for the stimulating antigen.

DNA ligase

an enzyme that eventually joins the sugar-phosphate backbones of the Okazaki fragments

Medulla

an extension of the spinal cord into the brain that coordinates heart rate, circulation, and respiration heart pressure, digestive functions, AUTONOMIC FUNCTION, release Norep + Ep

Transposons

are small fragments of DNA that can move between different regions of the genome. Movement of a DNA sequence, such as a transposon, from one chromosomal arm to another may alter the nucleotide sequence of each chromosome but would not reduce chromosome number

Cadherins

are transmembrane proteins which play a primary role in cell-to-cell adhesion (remember that C stands for cell-to-cell), forming adherens junctions to bind cells within tissues together.

Integrins

are transmembrane receptors that modulate cell-to-extracellular matrix interactions. Specifically, these proteins often attach the cell to collagen and fibronectin fibers.

Anticodon

at one end of tRNA, is responsible for recognizing mRNA codon to be translated (a sequence of 3 nucleotides that is complementary to the codon of mRNA)

A blastomere is a _____ and a blastocyst is _____.

cell produced by cleavage; a hollow ball of cells

Septate hyphae

cells are separated by septae

Sertoli cells

cells found within the seminiferous tubules that provide metabolic support for the spermatids

glial cells

cells in the nervous system that support, nourish, and protect neurons, no AP 1. Schwann cells (PNS) 2. oligodendrocytes 3. astrocytes 4. microglia 5. ependymal cells

Aseptate

cells joined together to a long tube

X-linked dominant

characterized by a lack of father-son transmission, but all daughters of an affected father are affected. Affected mothers have a 50% probability of having an affected child.

Neuromodulators =/= releasing factors

chemicals released in the nervous system that influence the sensitivity of the receiving neuron to neurotransmitters

Sense strand

coding strand of DNA

Psychrophile

cold loving

Instead of a promoter, prokaryotic ribosome has a ribosome binding site =Shine-Dalgarno sequence

complementary to pyrimidine rich region on the small subunit helps position the initiation machinery on the transcript

spliceosome

complex of enzymes that serves to splice out the introns of a pre-mRNA transcript

Microtubules

composed of alternating α- and β-tubulin subunits that assemble into hollow tubes. They are involved in various forms of movement within the cell; microtubules form the mitotic spindle during cell division and are essential for cell motility as they form the core of cilia and flagella. Microtubules also facilitate transport of vesicles such as endosomes and other organelles from one location in the cell to another. The microtubules involved in intracellular transport originate near the nucleus on small organelles called centrioles and radiate out toward the plasma membrane.

Bohr Effect

decreased pH, increased CO2, and increased temperature all decrease the affinity of O2. ->release more O2 --> =active tissues enviro CURVE RIGHT SHIFT

Resistance can be changed thro

degree of constriction of arteriolar smooth muscle (precapillary sphincters) -> contract-> pressure goes up

During inspiration

diaphragm contracts,downward, flattens, alveolar volume increases, intra alveolar pressure decreases, external air rushes into alveolars, thoracic cavity (chest cavity) expands, pressure in the intrapleural space decreases,elevate the rib cage

vagus nerve

example of cranial nerve decrease HR and increase digestion -> parasympathetic division

1. Proof reading: DNA polymerases are equipped with both 5′-3′ and 3′-5′ exonuclease activity that allows them to remove and replace incorrect nucleotides at either end of a DNA strand. It cannot fix mistakes in the middle of a strand. 2. Nucleotide repair enzymes are required to excise thymine dimers. 3. Mismatch repair enzymes, which have endonuclease rather than exonuclease activity, are required to correct mismatched nucleotides within a DNA strand. 4. Damaged bases are removed after replication by base excision repair enzymes with endonuclease activity.

exonuclease activity that allows them to remove and replace incorrect nucleotides at either end of a DNA strand endonuclease: middle Excision repair: Damage to one or a few bases of DNA is often fixed by removal (excision) and replacement of the damaged region. In base excision repair, just the damaged base is removed. In nucleotide excision repair, as in the mismatch repair we saw above, a patch of nucleotides is removed.

Cardiac output

heart rate x stroke volume

Cardiac Action Potential

fast sodium channel is voltage gated slow Ca2+ channel opens for longer and allows membrane depolarization to last longer in cardiac muscle, producing a plateau phase ->contraction for a longer time - To max the entry of Ca2+ into the cell, cardiac muscle has T tubules ---AP travel down along T tubles, allow entry of calcium from extracellular and introduce sarcoplasmic reticulum to release Ca2+ ->contraction of actin myosin fibers

Estrogens

female sex hormones The main androgens is testosterone, main estrogen is estradiol.

Centrosomes and Centrioles

form mitotic spindle; needed to form cilia and flagella

· Recombination Frequency:

frequency with which a single chromosomal crossover will take place between two genes during meiosis. Increase for farther away

osteon

functional unit of compact bone -Within each osteon, lacunae (spaces containing osteocytes) connect to one another via microscopic channels called canaliculi, which allow osteocyte waste exchange and nutrient delivery.

Anaerobic respiration

glucose metabolism with electron transport and oxidative phosphorylation relying on an external electron acceptor other than O2.

Starvation leads to

glycogen breakdown and gluconeogenesis, then continued fasting leads to the production of ketone bodies by sustained fatty acid oxidation.

Catecholamines

in response to a stressor, the adrenal medulla releases catecholamines (norepinephrine and epinephrine) that -Vasoconstriction of blood vessels and reduced blood supply to organs that carry out nonessential functions (eg, stomach, intestines, kidneys) conserve oxygen and nutrients for organs that are necessary for immediate survival. Vasodilation of blood vessels increases blood flow to organs essential for immediate survival (eg, heart, skeletal muscle). -both hormones promote glycogenolysis. By inhibiting the enzymes that mediate glycogen synthesis, norepinephrine and epinephrine also inhibit glycogenesis -Increased heart rate and cardiac muscle contractility promote increased blood flow to the brain, lungs, and skeletal muscles, allowing an organism to process and execute a response to the stressful stimulus. -Dilation of airways (bronchioles) enables increased respiratory function and oxygen delivery to tissues.

Positive-sense viral RNA

is similar to mRNA and thus can be immediately translated by the host cell.

ischemia

lack of blood flow, lead to tissue damage due to lack of O2

Thallus

large fungi structure

The glomerular filtration rate (GFR) is the rate (amount per unit time) at which fluid is filtered out of the glomerular capillaries (collectively known as the glomerulus) and into Bowman's capsule. GFR is proportional to the hydrostatic (blood) pressure within the glomerulus. As such, GFR can be expected to decrease if the afferent arterioles constrict (ie, because less blood enters the glomerulus) or efferent arterioles dilate

low blood pressure decreases the glomerular filtration rate, allowing more time for reabsorption and decreasing the amount of substance A in the urine. Blood pressure is the source of the energy that forces fluid into the capsular space. If the heart stopped and the blood in the glomerular capillaries had no hydrostatic pressure, fluid in the space around the glomerulus would flow back into the capillary bloodstream. This would occur because the protein-rich blood would be hypertonic with respect to the protein-poor fluid in the capsular space so that the fluid would flow down the osmotic gradient into the blood.

diastole pressure

lowest ARTERIAL pressure during cardiac cycle

Pulmonary resiliency

lungs' ability to recoil after being stretched 1. Elastic recoil refers to the elasticity of elastin fibers making up alveolar tissues. When stretched, these fibers exert a restorative force on the lungs following inspiration. 2. Surface tension refers to the tendency of a liquid to reduce exposed surface area due to attractive intermolecular forces between its molecules. Surface tension is signficant at alveolar surfaces due to hydrogen bonds between water molecules lining the alveolar sacs. Because surface area increases when the alveoli expand, surface tension exerts a collapsing pressure on the alveoli.

posterior pituitary hormones

made up of axonal projections from the hypothalamus, stores and secretes the hormones oxytocin and vasopressin (also called antidiuretic hormone [ADH]). Posterior pituitary hormones are synthesized in hypothalamic neurons and then transported down the axon to the axon terminals in the posterior pituitary, where they are stored. The secretion of stored hormones from the posterior pituitary is mediated by action potentials that cause exocytosis of neurosecretory vesicles.

anterior pituitary Hormones

made up of glandular tissue that synthesizes and secretes follicle-stimulating hormone (FSH), luteinizing hormone (LH), adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), growth hormone (GH), β-endorphins, and prolactin. The synthesis and secretion of hormones from the anterior pituitary is controlled primarily by neurohormones released from hypothalamic neurons. These regulatory neurohormones are secreted into the hypophyseal portal system, a network of small blood vessels that enables small quantities of hormones secreted from the hypothalamus to directly reach the anterior pituitary without being diluted in the circulation.

astrocytes

make extensive contact with blood vessels and regulate blood flow in coordination with synaptic activity and chemical changes. maintaining the chemical homeostasis of the interstitial space, including regulation of fluid and ion balance, pH, and neurotransmitter concentrations. They are also thought to play important roles in neuron development and structural maintenance, as well as coordination between neurons and other glial cells

Fruiting body

make spores for reproduction

Androgens

male sex hormones

tonsil

mass of lymphoid tissue on either side of the throat at the back of the tongue -catch pathogens

Veins lack what?

muscular wall

(+) RNA viruses

must at least code for RNA-dependent RNA polymerase in their genome. A piece of single stranded viral RNA which serves as mRNA

DNA replication enzymes

o Topoisomerase introduces negative supercoiling in the DNA double helix ahead of the replication fork to reduce the strain produced by unwinding, which causes positive supercoiling. o DNA helicase unwinds the DNA double helix and separates the parent strands at the origin of replication. o Single-strand DNA-binding protein binds to each strand to prevent spontaneous reannealing of unwound single-stranded DNA. o Primase synthesizes RNA primers and positions them at the beginning of each DNA strand. Only one primer is needed for leading strand synthesis, but lagging strand synthesis requires many RNA primers. o DNA polymerase synthesizes daughter strands in a 5′ → 3′ direction only. One daughter strand is synthesized continuously toward the replication fork (leading strand); the other strand is synthesized discontinuously in a direction away from the replication fork (lagging strand), with more and more segments added as the replication fork progresses. This process results in the formation of Okazaki fragments, short stretches of newly synthesized DNA separated by RNA primers. o DNA ligase joins Okazaki fragments.

directional selection

occurs when natural selection favors one of the extreme variations of a trait

Parallel evolution

occurs when two more closely related species (ie, descended from a more recent common ancestor) continue to evolve the same characteristics to adapt to similar environments.

Ependymal (CNS)

produce cerebrospinal fluid

Peroxisomes

produce hydrogen peroxide H2O2 that can detoxify in liver, also for lipid breakdown. Catalase: convert it to h2o and o2 to prevent damaging cells.

The large intestine is composed of

the cecum, colon, and rectum. The cecum, the first segment of the large intestine, is a small pouch connected to the appendix. Ingested food would pass normally from the ileum into the large intestine

The majority of gas exchange occurs at the alveoli, which are located at the ends of the respiratory tract branches.

respiratory bronchiole can perform gas exchange

Formation of cDNA

reverse transcriptase produces a single-stranded DNA molecule using mRNA as a template

Archea

single celled, live in extreme environments, cell wall lacks peptidoglycans

myofiber

skeletal muscle cell

hapten

small molecule that has to bind to a larger molecule(carrier) to form an antigen

Smooth ER function

steroid synthesis in gonads, detoxificaiton of drugs and poisons, glycogen breakdown in liver

Basophil

store and release histamine; allergic reactions

Gram+

strong staining, dark purple, only one layer of very thick peptidoglycan, contains only exotoxins

cDNA cloning steps

target messenger RNA (mRNA) sequences are mixed with complementary primers known as oligo(dT) primers, which are composed of thymine nucleotides. These primers bind the mRNA 3′ poly-A tail, and the enzyme reverse transcriptase uses dNTPs to generate a single strand of cDNA from the mRNA. The mRNA strand is degraded and the resulting cDNA sequence (eg, BLM cDNA) is amplified using DNA polymerase in PCR. The cDNA sequence containing the gene of interest can then be inserted into a cloning vector, a circular DNA molecule found in bacteria and viruses. The foreign cDNA and vector are cut by a restriction enzyme, generating complementary sticky ends that anneal when both molecules are mixed together. DNA ligase joins the cDNA to the vector, resulting in the formation of a recombinant vector that can be transfected (inserted) into cells

forebrain

telencephalon(cerebrum) and diencephalon(thalamus+hypothalamus)

thalamus

the brain's sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

Deoxyribonucleotides

the building blocks of DNA, are each composed of a phosphate, a deoxyribose sugar, and one of four nitrogenous bases (A, T, C, or G). -Cytosine (C) and thymine (T) are one-ringed bases known as pyrimidines. Thymine contains a methyl group (-CH3) attached to the carbon atom in the fifth position, a feature that helps distinguish it from cytosine. -Guanine (G) and adenine (A) are two-ringed bases known as purines. Guanine has a carbonyl group (-C=O) at the sixth position that helps differentiate it from adenine.

Ketone bodies

the by-products of the incomplete breakdown of fat acetone, acetoacetic acid, beta-hydroxybutyric acid

relative refractory period

the period of time following an action potential, when it is possible, but difficult, for the neuron to fire a second action potential, due to the fact that the membrane is further from threshold potential (hyperpolarized)

Blood pressure

the pressure that is exerted by the blood against the walls of blood vessels, Measuring the systematic arterial pressure

Leydig cells

tissue between Seminiferous tubules ---contains interstitial cells ->for androgen synthesis.

hn RNA

the primary unmodified transcript

saltatory conduction

the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials.

Epitope

the small part of an antigen molecule to which an antibody attaches itself

Muscle tone

the state of balanced muscle tension that makes normal posture, coordination, and movement possible

parasympathetic nervous system continually inhibits depolarization of SA node.

the vagus nerve contains preganglionic axons which synapse in ganglia near SA node. These preganglionic nerves release ACh to inhibit the depolarization by binding to receptors on the cells of SA node

Stroke volume

the volume of blood pumped out by a ventricle with each heartbeat

Topoisomerase

unwinds ahead of replication forks by breaking, swiveling, and rejoining DNA strands

absolute refractory period

time during which another action potential is impossible; limits maximal firing rate

ureter

tube that carries urine from the kidney to the urinary bladder

carrier proteins:

uniport: carry one protein at a time Symport: carry 2 at a time in the same direction Antiport: carry 2 in opposite directions

Gram-

weak staining, pink, one layer of thin peptidoglycan, and periplasmic space, additional layer containing lipopolysaccharide ->increased resistance to antibiotics, contains both endo and exotoxins