final exam bio Flashcards

Question

4 major layers of the vertebrate gut

Answer 1

1. mucosa 2. submucosa 3. muscularis 4. serosa

Answer 2

lines inside of gut epithelial cells that absorb nutrients, seal off digestive contents from body fluids glandular cells: secrete enzymes, mucus, pH regulation

Answer 3

elastic connective tissue, neuron network, blood + lymph vessels neural network: local control of digestive activity

Answer 4

formed by circular layer (constricts gut diameter) and longitudinal layer (shortens + widens gut)m, does peristalsis - oblique layer (stomach only)

Answer 5

outermost gut layer, connective tissue that is continuous w/ mesentery (tissue that suspends dig organs in abdomen) secretes lubricating fluid to reduce friction between organs

Answer 6

partially digested food

Answer 7

food mass from mouth

Answer 8

blocks trachea when swallowing

Answer 9

- elevation of soft palate to prevent food bolus from entering nasal passages - pressure of tounge seals back of mouth and prevents bolus from backing up - larynx moves upward, pushing glottis against epiglottis to prevent bolus from entering airway

Answer 10

middle part of larynx, where vocal cords are located

Answer 11

hydrochloric acid and protein digesting enzyme, pepsin + mucus (secreted by glandular cells)

Answer 12

secrete pepsinogen (precursor to pepsin) positive feedback mechanism

Answer 13

secrete H+ and Cl- HCL can activate pepsinogen to form pepsin

Answer 14

indentations in stomach that contain surface epithelial cells, mucous cells, chief cells, and parietal cells

Answer 15

when food enters stomach, stretch receptors in stomach wall are activated

Answer 16

major hormone that regulates acid secretion in the stomach - stimulated by stomach distension + presence of digested proteins (amino acids)

Answer 17

2: optimal pH for pepsin - helps unfold and break down proteins - kills unwanted bacteria

Answer 18

protects stomach wall from acidity and breakdown from pepsin

Answer 19

1-6 hours fat - small intestines

Answer 20

small intestine

Answer 21

proteins: endopeptidases, exopeptidases polysaccharides: hydrolysis by amylase (from pancreas), then disaccharidases triglycerides: hydrolyzed by lipase nucleic acids: hydrolyzed by nucleases (DNase, RNase)

Answer 22

starts here optimize absorption by intestinal villi: folds in lining of small intestine microvilli: projections of plasma membrane of epithelial cells (brush border) greatly increase surface area of intestine - have capillaries and lymphatic vessels (fat goes here)

Answer 23

the lymphatic vessels of the small intestine that absorb digested fats

Answer 24

duodenum - where digestive substances from pancreas and liver aid the digestive process

Answer 25

pancreas through exocrine cells - bicarbonate HCO3- cells - proteolytic enzymes: (further break down proteins) trypsin chymotrypsin carboxypeptidase lipase (breaks down fat) amylase (sugars) nucleases secretes into ducts that empty into the duodenum

Answer 26

liver, stored in common bile duct in gallbladder, released through bile duct when chyme enters small intestine - emulsifier

Answer 27

exocrine (secretes enzymes) endocrine (secrete glucagon and insulin) duct cells (bicarbonate ions)

Answer 28

glucagon (alpha cells) released when blood glucose levels are 2 low - causes live to convert glycogen to glucose and release into bloodstream insulin (beta cells) causes cells in liver, muscle and fat tissue to take up glucose from blood - stores as glycogen in liver and muscle, stopping use of fat as an energy source

Answer 29

form a hydrophilic coat around fats (polar/nonpolar side)

Answer 30

bile and churning motion of small intestine emulsifies fat into micelles lipase hydrolyzes fats in micelles into monoglycerides and free fatty acids in mucosal cell cytoplasm, hydrophobic molecules packaged into chylomicrons these are secreted into interstitial fluid of submucosa ((extracellular fluid) and taken up by lacteal (lymph nodes), transported from intestine to muscle tissue

Answer 31

structure that has molecules with hydrophilic head regions in contact with surrounding solvent, sequestering the hydrophobic tail regions in center

Answer 32

lipoproteins particles - protein coat that provides hydrophilic surface that keeps droplets suspended in cytosol of mucosal cell triglycerides, phospholipids, cholesterol, proteins

Answer 33

enable fats and cholesterol to move within bloodstream 1. chylomicrons 2. VLDL 3. IDL 4. LDL 5. HDL

Answer 34

small intestine reabsorbs 6-8L of 7-9L fluid release from stomach - active uptake of salts, passive following water - large int also absorbs - water soluble products absorbed by intestinal mucosal cell cytoplasm - nucleic bases active transport - pentoses just absorbed with other sugars

Answer 35

endocytosis - large peptides/proteins Na+ co transporters - amino acids H+ ion dependent co trans - di/tripeptides may reduce polypeptides to amino acids or may be carried across cell intact

Answer 36

nutrient molecules carried by capillaries in mucosal cells (intestinal villae) that collect into veins that join to form the hepatic portal vein -> capillary bed in liver

Answer 37

- excess glucose → glycogen - fats/amino acids → plasma proteins or sugars - lipids carbohydrates, etc. synthesize into cholesterol - albumin made (plasma protein imp for maintaining high pressures) - synthesizes lipoproteins that transport cholesterol - detoxifies substances - blood from liver carried to deliver nutrients to body

Answer 38

cecum, appendix, colon, rectum absorbs water and mineral ions from digestive contents - undigested remnants at end (feces) expelled from anus

Answer 39

signals from autonomic nervous system activity of neuron networks in digestive tube wall hormones secreted by digestive system respond to signals from sensory receptors that monitor volume (stretch) and composition (chemoreceptors) of digestive contents

Answer 40

enteric nervous system subdivision of PNS directly controls the GI system imbedded in lining of GI system, efferent/afferent/inter neurons included sensory neurons report on mechanical and chemical conditions motor neurons through intestinal muscles control peristalsis and churning of intestinal contents others control secretion of enzymes

Answer 41

chemoreceptors signal neuron networks to stimulate stomach to secrete hormone gastrin -> gastrin stims the stomach to secrete HCL and pepsinogen + contractions in stomach and intestine

Answer 42

hormone. released when chyme enters duodenum, prevents more chyme from entering till current has been neutralized by HCO3- secretion also stimed by secretin

Answer 43

cholecystokinin, hormone, stimulated release by fat in chyme (mostly) inhibits gastric activity (allows time for nutrients to be digested absorbed) and stimulates secretion of pancreatic enzymes and bile from gallbladder

Answer 44

glucose dependent insulinotrophic peptide, hormone from pancreas meal entering digestive tract stimulates it triggers insulin release (insulin stims uptake and storage of glucose)

Answer 45

determining appetite appetite center satiety center

Answer 46

stop eating: - insulin acting on cells of hypothalamus - glucose uptake by cells of hy - mechanoreceptor detect distention - chemoreceptors detect food hunger: absence of these

Answer 47

full of fat: secrete leptin hormone -> binds receptors in hypothalamus -> stims center that red appetite, inhibits center that stims appetite increase in met rate: oxidize fatty acids rather than convert them to fat low in fat -> less leptin increase in appetite

Answer 48

tiggers hunger hormone

Answer 49

peptide YY secreted by small int after meals suppresses appetite

Answer 50

condition in which pathogenic microorganisms penetrate host defenses, enter the tissues, and multiply

Answer 51

obligate intracellular parasites (multiply by taking control of host cells genetic material) not living (unable to generate energy) potential for rapid, large scale proliferation facts: classified on size, shape, chem comp, structure of genome, mode of replication fully assembled inf virus = virion RNA viruses compose 70% of all, error rate of enzymes in RNA rep, these show higher mutation rates than DNA virus

Answer 52

protein shell (capsid, made of capsomeres) surrounding nucleic acid core (DNA or RNA) 3 types: enveloped: outer phospholipid/glycoprotein coat) CoVs HIV naked: no envelope (papilloma) complex: extra structures (pox virus) only have enough genes to invade host cells genetic material and redirect its activity

Answer 53

single stranded RNA virus that stores its nuc acid in form of mRNA genome (HIV)

Answer 54

when DNA gets incorporated into the host cells genome by an integrase enzyme

Answer 55

viral DNA can stay dormant and be reactivated later

Answer 56

cytopathic effects, indicate viral damage to cells syncytium and inclusion

Answer 57

viruses released by infected cells - destruction of cell mem, organelles shut down metabolism genetic expression release lysosomes cell death latency

Answer 58

mass of cytoplasm containing several nuclei and enclosed in a membrane but no internal cell boundaries

Answer 59

body suspended in cytoplasm such as a granule

Answer 60

can produce toxins that disrupt normal cell func - done by damaging specific cells -> blocking transmission of signals, over stimulating cells so they malfunction cholera toxin -> disrupts ionic balance of cell membranes -> cells in small intestine secrete large amts of water into intestine -> diarrhea -> dehydration

Answer 61

inhibit formation of bacterial cell wall by blocking cross-linking of cell wall structure

Answer 62

inhibit protein synthesis by binding to the subunit of the bacterial ribosome (305 subunit)

Answer 63

blocks DNA syn by inhibiting bacterial enzyme (DNA gyrase) needed in this process

Answer 64

physical (barrier), chemical, genetic -skin: resist pathogen penetration, replication mucous membranes: (chem) prevent attachment to cell, directly inactivate virus lysozyme: damage bac cell walls, abundant in secretions acidic env of stomach (pH 2) specificity of viruses to host cell receptors (genetic)

Answer 65

innate immune system key players: inflammatory response, phagocytosis, complement, interferons, cytokines

Answer 66

adaptive,/acquired immune system key players: antibodies, T cells, B cells, accessory cells, cytokines

Answer 67

nonspecific acts sooner responses broad spectrum no memory of lasting protective immunity activation can occur in response to general components of pathogens or factors released by damaged cells PAMPs DAMPs PRRs

Answer 68

pathogen associated molecular patterns - found on pathogens lipopolusaccharide (LPS) (found on outer membrane of bacteria)

Answer 69

damage ass mol patterns cell components released during cell damage/death (presence of DNA in other than nucleus/mitochondria, triggers responses mediated by TLR9)

Answer 70

pattern recognition receptors id PAMPs and DAMPs found on some immune cells (phagocytic) (Toll-like receptors) TLRs (drosophila christine nelson nobel prize)

Answer 71

any # of subs, that are secreted by certain cells of immune system and have effect on other cells (Interferon, TNF(alpha and beta), Interleukins or growth factors)

Answer 72

polypeptide that produces fever by causing metabolic changes in hypothalamus (raise set point of hypothalamic thermostat) fever inhibits x of temp sensitive viruses (polio, cold, herpes zoster) and stims immune rxns (phagocytosis) exogenous (prod by inf agents) endogenous (prod by cells in body such as macrophages)

Answer 73

granulocytes monocytes lymphocytes

Answer 74

class of wbc, granules in cytoplasm (neutrophils, eosinophils, mast cells, basophils)

Answer 75

clear cytoplasm, larger, migrate to site of inf and divide /diff into macrophages and dendritic cells

Answer 76

agranulocytes (no granules in cytoplasm) found in lymph term for any 3 types NK: natural killer T cells B cells during development: B cells stay in bone marrow T cells migrate to the thymus

Answer 77

function mostly in innate immunity but also in adaptive

Answer 78

cell-mediated, cytotoxic adaptive immunity antigen receptors of T cells bind only to antigens that are displayed

Answer 79

for humoral, antibody driven adaptive immunity antigen receptors of B cells bind to epitopes of intact antigens on pathogens OR circulating free in body fluids

Answer 80

leukocyte, white blood cells

Answer 81

activated by cell and tissue damage induced by pathogen interferes with further pathogen replication/multiplication characteristics/stages 1. vascular changes - inc circulation - vasodilation - redness, warmth 2. swelling: leakage of vascular fluid - pus is exudate, typically white-yellow, yellow, or yellow brown - pain=stimulation of nerve endings 3. prod of chem mediators (molecules) that - cause fever, stim wbcs - TNF (chemotaxis, phagocytosis), IFN (inhibits virus replication), IL (activate wbc)

Answer 82

type of cytokine that induces directed chemotaxis in nearby responsive cells

Answer 83

activate when break in skin introd bacteria, release histamine, histamine and cytokines dilate local blood vessels, chemokines attract neutrophils

Answer 84

prod by basophils and mast cells found in nearby connective tissues increases the permeability of the capillaries to wbcs and some proteins, to allow them to engage pathogens in the infected tissues

Answer 85

tendency of cells to migrate in response to a chemical stimulus

Answer 86

type of endocytosis: cell membrane actively engulfs large particles or cells into vesicles ingestion phagolysosome formation destruction excretion

Answer 87

class of wbc capable of engulfing other cells and part types: neutrophils: type of granulocytes, short lived monocytes- large, a granulated macrophages- diff from monocytes

Answer 88

glycoprotein prod primarily by fibroblasts, lymphocytes, macrophages, epithelial cells, T cells binding of a virus to a host cell initiates IFN synthesis IFN secreted by cell into extracellular space binds to another host cell: induces prod of proteins degrades viral RNA or prevents translation of viral proteins not virus specific, activates NK cells, macrophages, enhances phagocytosis

Answer 89

nonspecific group of proteins found in plasma forms membrane -> attack complex that kills cells by creating holes in membrane (disrupts osmotic balance, intermembrane proteins) involved in both types of immunity

Answer 90

3 different complement pathways (as determined by activator) 1. classical: C1 binds antigen antibody complex 2. lectin: mannose-binding lectin (MBL) binds forgein surface 3. alternative: starts with complement protein C3 result: make complement proteins C6-C9 = membrane attack complex

Answer 91

RNAi (interference): cellular mech, destroys viral dsRNA, inhibits virus life cycle NK cells (lymphocytes not phagocytes) can be activated by interferon - secrete perforin: cretes pores in target cell, ruptures infected cells - secrete enzymes to degrade DNA, trigger apoptosis

Answer 92

keep players antigens immunoglobins (antibodies + receptors) lymphocytes (B and T)

Answer 93

antibody mediated immunity (humoral) plasma cells (derived from B cells) secrete antibodies that circ in blood, bind to antigens, clear them cell mediated specific T cells activated attack and kill forgein pathogens and inf cells

Answer 94

viruses, forgein cells, molecules that are capable of triggering immune rxns by lymphocytes can originate from within body (self antigen) or external environment (non self) - immune system doesn’t usually react to self antigens under normal homeostatic conditions due to neg selection of T cells in thymus (killing)

Answer 95

precise molecular group of an antigen that defines its specificity and triggers the immune response

Answer 96

gene segments: encode for receptors on surface of T and B cells, also encode for variable region on antibodies rearranged extensively, this leads to assortment of receptors on T and B cells each T or B lymphocyte has a protein receptor of unique config and is specific and reactive to a specific antigen

Answer 97

unique mechanism of genetic recombination that occurs only in developing lymphocytes during the early stages of T and B cell maturation involves recombination, results in highly diverse repertoire of antibodies/immunoglobulins and t cell receptors found on B cells and T cells during B cell diff, random V and J DNA segments join with C -> functional light chain gene DNA between V and J deleted assembly of heavy chains and formation of T cell receptor occurs similarly

Answer 98

unique mechanism of genetic recombination that occurs only in developing lymphocytes during the early stages of T and B cell maturation involves recombination, results in highly diverse repertoire of antibodies/immunoglobulins and t cell receptors found on B cells and T cells polypeptide encodes for variable region in antibody molecule

Answer 99

clone: each genetically unique line of lymphocytes arising from the gene segment rearrangement millions of genetically different clones of T and B cells are generated, each responds to 1 specific antigen T and B cells then migrate to lymphoid tissues

Answer 100

spec organ of immune system where T lymphocytes mature each T cell attacks a different antigen (the receptor is specific to the antigen) T cells that attack the body’s own proteins are eliminated in the thymus

Answer 101

1. hematopeietic stem cell undergoes diff and genetic rearrangement to prod immature lymphocytes with diff antigen receptors 2. those that bind to antigens from the body’s own tissues are destroyed, rest mature into inactive lymphocytes 3. those that encounter matchin forgein antigen are activated to prod many clones of themselves

Answer 102

give rise to all other blood cells through process of haematopoiesis located in red bone marrow

Answer 103

large glycoprotein molecules serve as both: 1. antibodies (aka lg; are secreted by plasma cells (wbcs that are derived from B cells and secrete large vol of antibodies) , these reside in blood plasma - 2. membrane receptors of mature B cells (IgD)

Answer 104

IgM IgG IgA IgE IgD

Answer 105

surface of unstim B cells (as monomer), free in circulation (as pentamer) ‘ 1st antibodies sec by B cells in primary response, activates agglutination rxn, complement system and phagocytic activity of macrophages

Answer 106

blood + lymphatic circulation most abundant antibody in 1ry and 2dry responses, crosses placenta (passive imm to fetus) stim phagocytosis and complement system

Answer 107

body secretions blocks attachment of path to mucous membranes, confers passive immunity for breastfed infants

Answer 108

skin + tissue lining GI and reps tracts (sec by plasma cells) stims mast cells and basophils to release histamine; triggers allergic responses

Answer 109

surface of unstim B cells membrane receptor for mature B cells, probably imp in B cell activation (clonal selection)

Answer 110

excessive activation of wbcs (mast, basophils) by antibody IgE - result in inflammatory response

Answer 111

type of antigen presenting cell (APC) present in tissues in contact with the external environment, such as skin, lining pf nose, lungs stomach intestines once acti, migrate to lymph nodes + interact w/ T + B cells to initiate adaptive immune response

Answer 112

nearly all antigens elicit helper T response trigger both a humoral (makes antibodies) and cell mediated response CMI cytokines from helper T cells: 1. initiate antibody prod (to neutralize pathogens) 2. activate T cells to kill inf cells (INF, IL, TNF, chemokines)

Answer 113

1. an antigen fragment must be displayed in an APC (antigen presenting cell) (ex. dendritic cells, macrophages, B cells) having MHC class I + II proteins distinguishes an APC from other cells ( most body cells have MHC class I proteins) 2. antigen must bind to T cells receptor on the helper T cell

Answer 114

specialized B cells, secrete antibodies to surrounding tissues

Answer 115

unite with: opsonization (coat virus/pathogen) immobilize: agglutinate (aggregate): antibodies can cross link call attention to: binding of Ab enhances phagocytosis recognition neutralize: Abs fill receptor site on virus, prevents attachment to host cell destroy: int of Ab with complement (complement fixation) ruptures some viruses

Answer 116

antigen must be processed and presented by specific apcs (dendritic, b cells, macrophages) or by other infected cells antigen is complexed with other proteins (MHC) and transported to the cell membrane

Answer 117

expressed on mature helper T cells (Th) (also monocytes, macrophages, dendritic cells) - copreceptor for T cell receptor (TCR) - specific for the class II MHC protein - HIV infects them

Answer 118

predom expressed on surface of cytotoxic T cells (can also be found on others ex. NK cells, dendritic) - co receptor for TCR - CD8 is specific for class I MHC protein

Answer 119

initially, some thymocytes express both CD4 and CD8 proteins

Answer 120

immature cells in the thymus

Answer 121

major histocompatability complex group of genes that encode proteins (MHC antigens) found on the cell membrane in humans MHC genes -> HLA human leukocyte antigen genes all tissue cells (except mature rbcs) are marked w a characteristic combo of histocompatibility antigens on the surface of the cell membrane, have mechanisms for processing and presenting antigens in association with MHC molecules (this signals immune system if cell is normal or inf)

Answer 122

i professional antigen presenting cells immune cells that specialize in presenting a forgein antigen to a helper T cell main types: dentritic DC macrophages B cells have both MHC I and II

Answer 123

- occur on all nucleated cells (except rbcs) present epitopes to cytotoxic T lymphocytes (CTL’s) signal to immune system that cell is normal self cell in normal cell, proteins found in cytoplasm are degraded by proteasomes and processed into self antigen epitopes these bind within the MHC I antigen binding cleft and are presented on the cell surface

Answer 124

greater variance in MHC antigens between the donor and recipient, greater chance of transplant rejection

Answer 125

normally occur on APCs (macrophages, dendritic cells, B lymphocytes - CD4 (on helper T cell) docks to a n APCs MHC class II molecule - this binding promotes sec of cytokines by APC - cytokines stimulate proliferation of helper T cells helper T;s secrete other cytokines to initiate both humoral response (sec of antibodies by plasma cells) and CMI (attack on infected cells)

Answer 126

cytotoxic T lymphocytes expresses CD8+ receptors and T cell receptors TCRs CTL’s CD8 receptor docks to a MHC class I molecule, if it fits the epitope, triggers cell death

Answer 127

1. antigen/MHC complex binds to T cell receptors (plus co-receptor) 2. co-stimulation (ex. cytokines released from APC can activate T cells) 3. cells undergo mitosis diff into memory t cells t helper cytotoxic

Answer 128

- distinguished from other lymphocytes by presence of T cell receptors on surface - originate as precursor cells in bone marrow, develop in thymus gland - immature cells in thymus: thymocytes (can be double positive sometimes (CD4 and CD8)), eventually down regulate expression of CD# cell surface receptors - differentiation continues after leaving thymus, in secondary lymphatic organs and tissues (lymph nodes, spleen, tonsils), which is where lymphocytes interact w each other and interact with APCs naive T cells: not need exposed to an antigen memory T cells: interact later w antigen t helper: (CD4 and MHCII) - B and T cell growth and activation - release chemical factors: IL, TNF, IFN cytotoxic T cells (CD8 and MHCI) - kills specific cells - perforins: proteins that punch holes in membranes (osmotic gradients) - granzymes: enzymes that attack proteins of target cells

Answer 129

1. have to bind their T cell receptors to the MHC protein that is presenting the antigen to them (MHC and antigen are on APC) 2. have to have co stim. can be caused by: - cytokines released from APC - binding of other molecules like CD28 on T cell with B7 molecule on APC

Answer 130

1. release cytokines to make clones (will have T cell receptors spec spec for antigen) 2. stim B cells to make memory B cells (have B cell receptors spec to antigen) and plasma cells (that will make antibodies spec to that antigen) 3. secrete cytokines that can help activate cytotoxic T cells (among other things, like stim macrophages)

Answer 131

class of lipids diffuse readily across cell membrane

Answer 132

fused ring system 3 cyclohexanes and 1 cyclopentane many carbon hydrogens (makes nonpolar) many functional groups can be attached

Answer 133

fungus steroid - same function as cholesterol in animals: build and maintain membranes, regulates membrane fluidity over temperatures

Answer 134

plant steroid - structural comp of cell membrane

Answer 135

plant steroid pollen tube formation, cell expansion and elongation, vascular differentiation

Answer 136

classified as a modified steroid (sterol/steroid alcohol) essential structural comp of mammalian cell membranes (permeability + fluidity) - disturbs close packing of phospholipids (lipid bilayer) - imp comp for manufacture of bile acids, steroid hormones and vitamin D - can get from body or synthesized in body from carbs, proteins, fat - carried though blood in lipoproteins (HDL,LDL) - build up leads to atherosclerosis

Answer 137

steroid hormone: steroid that acts like hormone - can be grouped into 5 types by receptors to which they bind 1. glucocorticoids (corticosteroid) (cortisol) 2. mineralocorticoids (corticosteroid) (aldosterone) 3. androgens (sex steroid) 4. estrogens (sex steroid) 5. progestins (sex steroid) corticosteroid: syn in adrenal cortex (adrenal gland atop of kidneys)

Answer 138

signaling molecule secreted by cell that can alter activities of any cell with receptors for it - prod by 1 tissue and trans through bloodstream (not always) to another tissue to alter its physiological activity - hormones and local regulators grouped into 4 classes based on chem structure - reg by feedback pathways - effective in low concentrations (amplification) - can be either hydrophilic/phobic - target cells may respond to more than one hormone, and different target cells may respond differently to the same hormone involved with controls of: - development and function of gonads - metabolism (thyroid hormone) - inflammation - salt and water balance in body fluids - molting in insects and crustaceans (ecdysone)

Answer 139

steroid hormones are lipid soluble 1. sex steroids 2. corticosteroids - glucocorticoids and mineralocorticoids

Answer 140

subset of sex hormones that produce sex differences or support reproduction - androgens estrogens and progestins

Answer 141

most medical steroid drugs (prednisone) - syn from cholesterol within adrenal cortex - include glucocorticoids and mineralocorticoids

Answer 142

maintain normal blood glucose lvls - stims glucose syn from fats and proteins - inhibition of glucose uptake in muscle + adipose - stims breakdown of fats and proteins -> amino acids + fatty acids used as alt energy -

Answer 143

maintain blood volume and control electrolytes + water lvls by promoting Na retention in kidney (aldosterone)

Answer 144

class of steroids that interact with androgen receptors to inc muscle and bone synthesis - can be natural or synthetic - inc prod of actin and myosin proteins, these can be incorporated into existing myofibrils and add to muscular strength - block fx of stress hormone cortisol on muscle tissue - affect # of cells that develop into fat storage cells, by favoring cellular diff into muscle cells instead

Answer 145

growth (HGH: somatotropin) reproduction (LH: lutenizing hormone: stims ovulation) sexual development (testosterone: sperm prod) use and storage of energy (glucagon: converts stored glycogen into glucose) response to physical stress/trauma: cortisol lvls of fluids/salt/sugar in blood: ADH, aldosterone

Answer 146

- controls activities that involve slower, long acting responses - works in parallel with nervous system - collection of glands that secrete hormones usually passed through bloodstream to arrive at target organ, with cells possessing appropriate receptor - includes 4 major types of cell signaling

Answer 147

not part of endocrine system - secrete prod usually passed outside body (sweat glands, salivary glands) - pancreas has exocrine glands

Answer 148

hormone that regulates hormone secretion by another endocrine gland (ex. thyroid stimulating hormone)

Answer 149

1. classical endocrine signaling: endocrine glands secrete hormones (over a distance) 2. neuroendocrine signaling: neurosecretory neurons release neurohormones into circulatory system 3. paracrine regulation: cells release local regulators that diffuse through extracellular fluid to regulate nearby cells 4. autocrine regulation: cells release local regulators that regulate the same cells that produced it

Answer 150

characterized by mol structure 1. amines - based on tyrosine - ex. epi, norepinephrine, thyroxine 2. peptides - amino acid chains - ex. growth factors, PYY (suppresses appetite) 3. steroids - can be gen from cholesterol - ex. aldosterone, cortisol, sex hormones 4. fatty acids - paracrine and autocrine regulation - ex. prostaglandins

Answer 151

- act on array of cells and have variety of fx: cons/dilation vascular smooth muscle cells agg/disagg of platelets sensitize spinal neurons to pain dec intraocular eye pressure reg inflammatory mediation reg Ca movement control cell growth - potential, short half-life before being inactivated and excreted - sometimes defined as hormone like lipid compounds - bind to cell surface 7-transmembrane receptors: G-p coupled receptors - autocrine and paracrine type mediators - prod by ox of chemicals by cyclooxygenases (COX-1 and COX-2) - NSAIDs (aspirin, ibuprofen) inhibit cyclooxygenase

Answer 152

binding of a hormone to a receptor activates many proteins, which activates even more proteins etc. - reason why hormones effective in low concentrations - 1 molecule epi acting on liver cell liberates 10^6 glucose molecules

Answer 153

bind to surface receptors activating 2nd messenger pathways inside cells to elicit a cellular response (epinephrine) - usually amines, peptides

Answer 154

bind to receptors inside cells, activating/inhibiting genetic reg proteins (aldosterone) - usually steroids

Answer 155

- inc reabsorption of Na and water and secretion of potassium in the kidneys - part of RAAS- raises BP (higher water=higher blood volume)

Answer 156

glands: pineal pituitary thyroid parathyroid hypothalamus adrenal medulla adrenal cortex testes and ovaries islets of langerhans (pancreas)

Answer 157

produces melatonin: hormone that fx the mod of wake/sleep patterns and seasonal functions

Answer 158

int w/ hypothalamus to set body’s daily biorhythms in some vertebrates (fish, amphibians, reptiles) helps animal change skin color

Answer 159

review: under thalamus, has centers for apetite control, osmoreceptors, prod ADH (released by pituitary gland), temp reg, releases TRH (stims release of LH and FSH) - prod and secretes releasing/inhibiting hormones that reg secretions by anterior pituitary - prod ADH and oxytocin (stored and released by posterior pituitary) - produces tropic hormones that control secretion of anterior pituitary hormones other hormones: TRH, CRH, GnRH GHRH, somatostatin (GHIH) (also secreted at locations in digestive system, suppresses release of gastrin, CCK, GIP, secretin, etc.)

Answer 160

uttering contractions during birth, breast milk release, bonding

Answer 161

posterior: contains neurosecretory nerve endings from hypothalamus - secretes 2 hormones anterior: non neuronal endocrine cells - sec 8 hormones

Answer 162

1. prolactin (PRL) prod milk - mammary glands 2-3. gonadotropins (FSH (egg dev, female sex hormones, sperm prod) and LH (ovulation, male sex hormones)) prod gametes and hormones - testes/ovaries 4. TSH inc rate of metabolism - thyroid gland 5. ACTH (adrenocorticotropic) reg fluid balance, helps body cope w stress - adrenal cortex 6. GH promotes growth - muscle, bone , etc. glucose metabolism, stims IGF (insulin growth factor) release in liver 7. melanocyte stim hormone (MSH) promotes skin darkening - melanocytes in skin (prod by cells in intermediate lobe) 8. endorphins inhibit pain perception - pain pathways of PNS

Answer 163

ADH/vasopressin inc permeability- nephrons in kidneys oxytocin - uterus (stims contractions), mammary glands (stim milk release)

Answer 164

causes inc prod and release of corticosteroids (glucocorticoid and mineralocorticoids) - stims glucocorticoid sec in adrenal cortex - glucose + cortex + steroid (role in metab of glucose, synthesis in cortex and steroid structure) - dampen immune response - aldosterone sec mediated by angiotensin II but also by ACTH by lesser extent

Answer 165

thyroid hormone stim metabolism, growth and development and maturation (also T3 and T4 inc catecholamine fx) - sec thyroxine (T4) (major hormone, longest half life) triiodothyronine (T3) calcitonin (calcium homeostasis) - negative feedback from thyroid hormones over hypothalamus as well as anterior pituitary (TRH and TSH)

Answer 166

low thyroid output - physically + mentally sluggish - low HR, weak pulse - children: cretinism (stunted growth, diminished intelligence)

Answer 167

overprod of thyroid hormones - irregular, rapid HR - irritable - insomnia - weight loss - emotional instability

Answer 168

cause of hyperthyroidism - exopthalamos - enlarged thyroid autoimmune disease: antibodies activate TSH receptors which stim prod of T3 and T4. thyroxine receptors in pituitary are activated by surplus of T3/T4, suppressing release of TSH. HIGH lvls circulating thyroid hormones (T3 T4) LOW TSH lvls

Answer 169

enlargement of thyroid due to insufficient iodine in diet - iodine needed for T3 and T4 to be prod in response to stim by TSH no T3/T4, TSH not negatively feedbacked -> thyroid growth

Answer 170

peptide hormone - secreted by parafollicular cells (C-cells) in thyroid gland - acts to red blood Ca by: 1. stim Ca deposition in bone (inhibits osteoclast activity) 2. inhib dissolution of Ca from bone 3. in kidney, inhibits reabsorption of Ca allowing it to be excreted in urine - secretion is stimulated when Ca lvls in blood above normal - Ca release from bones regulated by parathyroid hormone PTH

Answer 171

lifelong process. - mature bone tissue removed from skeleton (bone resorption) and new bone tissue is formed (ossification) in adults, ~10% bone remodeled each yr

Answer 172

process by which osteoclasts break down bone and release minerals, resulting in transfer of Ca from bone fluid to blood

Answer 173

osteoblasts secrete new bone

Answer 174

osteoblasts secrete new bone

Answer 175

secrete parathyroid hormone 4 parathyroid glands reg Ca lvl in blood PTH acts to increase concentration of calcium in blood (opp of calcitonin) - calcium sensing membrane receptors in parathyroid gland monitor Ca lvls in extracellular fluid - low lvls stim release of PTH - stims activation of vitamin D, which promotes Ca absorption into blood from food in small intestine - enhances active reabsorption of Ca from kidney - stims Ca release from bone

Answer 176

- on top of kidney medulla (inner) secretes: epi and norepi - catecholamines (der from tyrosine) - sec in response with sympathetic fight or flight system cortex (outer) -secretes: cortisol, aldosterone and androgens

Answer 177

preps body for handling stress/physical activity HR inc break down of glycogen, fats -> glucose, fatty acids for energy can bind to 3 diff receptors (alpha, B1, B2) - alpha receptors on smooth muscle of blood vessels: vessels constrict -> less blood flow to peripheral regions (pale) - bind B1 on heart cells: cont inc -> blood flow inc - bind B2 on liver cells: glycogen breakdown to glucose overall increases energy - dilates vessels in skeletal muscles, heart, lungs, constricts others (raised BP) - red blood flow to kidneys -> red water loss - inhibits smooth muscle cont inc break intestine -> slow digestion

Answer 178

glucocorticoids: normal glucose lvls (anti-inflammatory cortisol, dampens immune system) mineralocorticoids: reg Na balance, extracellular fluid volume (aldosterone) androgens: stim/control development + maintenance of male characteristics (sec in small amts)

Answer 179

(cortisol: stress hormone; inc BP + blood sugar and red immune responses (anti inflammatory), decreases amino acid uptake by muscle and inhibits protein synthesis)

Answer 180

adrenal cortex hormone - reg amt of Na+ reabsorbed from fluids in kidney - reg amt of Na+ absorbed from foods in intestine - red amt of Na+ secreted by salivary and sweat glands - inc K+ secretion into kidney tubule (and resulting excretion) (Na/K pumps)

Answer 181

renin: enzyme that converts a protein to angiotensin angiotensin: peptide hormone that raises BP by constricting vessels and stim release of aldosterone 1. low blood volume -> kidneys sec renin 2. renin stims prod of angiotensin I (converted to angiotensin II by ACE) angiotensin II: causes constriction of vessels -> inc BP 3. angiotensin stims sec of aldosterone (inc reabsorption of sodium and water in kidney) from adrenal cortex this inc volume of fluid in body -> inc BP

Answer 182

islet of langerhans: where endocrine cells of pancreas are located insulin (beta cells): lowers blood glucose conc, inhibits conv of non carb molecules into glucose glucagon (alpha cells): raises glucose by stim glycogen, fat and protein degradation reg blood glucose lvls

Answer 183

hormone: facilitates glucose uptake from blood into cells, storing it as glycogen in liver and muscle when insulin is absent/low: glucose not taken up and body begins to use fat as energy source (ketoacidosis, lower pH bc of end product acetones)

Answer 184

low insulin production/action symptoms freq urination (using water to tru to excrete excess glucose) inc thirst (replace excreted water) inc apetite (low glucose = proteins + fats broken down for energy, replace) type 1: pancreatic beta cells destroyed by autoimmune rxn (need insulin injections) type 2: insulin secreted, but target cells have alteres insulin receptors complications: protein breakdown (use for energy) weakens blood vessels (poor circulation = tissue degeneration) - blindness, kidney failure, neuropathy

Answer 185

characterized by excessive thirst + urination (diuresis) - several types of DI - most common is neurogenic DI caused by deficiency in antidiuretic hormone (ADH) - nephrogenic DI caused by insensitivity of kidneys to ADH

Answer 186

ovaries sec estrogen progesterins testes androgens

Answer 187

prod in gonads (testes, ovaries) reg development of reproductive systems, sexual characteristics and mating behavior androgens: anabolic steroids (testosterone) estrogens (estradiol-principal estrogen) progestins (progesterone- principal) (natural/syn steroid hormone that maintains pregnancy and prevents further ovulation during pregnancy inc endometrium)

Answer 188

based on neg feedback regulation d stable internal condition of the body resulting from the body’s ability to elicit responses to counteract changes, thereby restoring stasis, or balance. ex. pH of the blood is normally maintained within the narrow range of 7.35 to 7.45, whereas the gastric fluid in the stomach has a pH that generally ranges from 1 to 2. ions in ECF regulated (osmotic balance) maintaining conc of O2 and CO2

Answer 189

-sensors that detect changes in chemical content, such as the amount of O2 in the blood. They are found in the aorta and carotid arteries and can also send signals to the cardiac centers in the brainstem where the information they provide is integrated with the information from the baroreceptors. -can also detect levels of plasma H+, and thus are important for pH regulation. To help tightly regulate the pH of the ECF, the body often employs the bicarbonate buffering system which can be described by the equation: CO2+H2O  H2CO3(carbonic acid)  HCO3 - (bicarbonate) + H+

Answer 190

may result when one’s ability to breathe is debilitated COPD ( amyotrophic lateral sclerosis or myasthenia gravis) when decreased respiration causes an increase in the blood CO2 levels. shift the equation above to the right, producing relatively more H+ and decreasing blood pH.

Answer 191

can occur if the kidneys are not adequately removing enough acid from the body, or if other compensatory mechanisms (such as the bicarbonate buffering system, or respiratory compensation, whereby the rate and depth of breathing is increased in order to exhale more CO2) are insufficient ketoacidosis: body’s inability to control prod of ketone bodies by fatty acid breakdown -> accumulation of molecules red PH

Answer 192

diabetic: lack of insulin to break down glucose leads body to switch to fatty acid breakdown alcoholic: alcohol can inhibit the process of gluconeogenesis, which reduces glucose production. This, in turn, directs the body to metabolize fatty acids for energy, again resulting in the production of ketones. (smell of acetone due to ketones)

Answer 193

pH abnormally high CO2 lvls fall (paper bag) bicarbonate buffering shifted to left CO2 + H2O  H2CO3 (carbonic acid)  HCO3 - (bicarbonate) + H+

Answer 194

hypothalamus 1. stim thirst 2. directs posterior pit to secrete ADH

Answer 195

obtain heat energy from environment by controlling rate of heat exchange with surroundings - lower metabolic rate (inc with temp) - invert fish and amphibians - small surface to volume ratio (retain more body heat)

Answer 196

period of inactivity aligned w variations in temp 1. hibernation 2. estivation (summer)

Answer 197

obtains heat energy from int rxns - modifying insultation, minimizing heat uptake, evaporative cooling (panting + sweating), redirecting blood flow, vasodilation/constriction

Answer 198

In response to lower environmental temperatures, an organism can conserve body heat by constrict- ing blood vessels near the body surface and enlarging more proximal blood vessels that are nearer to the body core. This redirects blood flow away from the body surface where the heat carried by the blood would be dissipated to the environment. Similarly, blood vessels that reside adjacent to the surface of the body can be dilated, while those residing more internally can be constricted, thereby shunting warm blood to the body surface, where heat can be released to the surrounding air.

Answer 199

, a temperature gradient is established between the warm arterial blood flowing outward in the body’s extremities and the cooler venous blood returning inward from the extremity to the body core. At any given point, heat is transferred between an artery and an adjacent vein, resulting in the conservation of heat.

Answer 200

located in the skin and the hypothalamus of the brain.

Answer 201

neurons/neuronal endings in walls of atria of heart, aortic arch and carotid sinuses mechanical stretch receptors detect stretch in vessel walls send APs to brain stem

Answer 202

epithelial connective muscle nervous

final exam bio Flashcards

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