Mcat Biology Review Flashcards

Front 1

lactic acid

Back 1

what pyruvate is converted to under anaerobic conditions, uses up 1 NADH and produces water and heat by-products. Reverse process occurs in the liver.

Front 2

alcoholic fermentation

Back 2

pyruvate converts to ethanol under anaerobic conditions, uses 1 NADH and produces CO2 as a by-product

Front 3

digestion of peptides

Back 3

protein --> stomach (gastrin stimulates the release of HCl and pepsin(ogen))- peptides --> small intestine (enterokinase, aminopeptidase, dipeptidase)- amino acids/dipeptides --> (active transport) bloodstream and epithelial cells --> ammonia/build new proteins --> ammonia enters urea cycle

Front 4

3 types of hormones

Back 4

1) amino acid based (catecholamines)- act via 2nd messengers/direct regulation of gene expression
2) peptide (ADH, insulin)- 1st messgeners, act via receptors and 2nd messengers
3) steroid (cholesterol derived, sex hormones)- bind to DNA --> transcription of specific genes

Front 5

erythropoeitin

Back 5

secreted by the kidney in response to decreased renal O2 levels --> stimulates bone marrow to produce more RBCs

Front 6

estrogen

Back 6

stimulates development of female reproductive structures, thickening of endometrium. Secreted by ovarian follicles and corpus luteum.

Front 7

progesterone

Back 7

secreted by the corpus luteum, stimulates development and maintenance of endometrium.

Front 8

intestinal secretions

Back 8

maltase, sucrase, lactase, aminopeptidase, dipeptidase, enterokinase (activates trypsinogen), CCK (stimulates release of bile)

Front 9

vitamins

Back 9

A, D, E, K = lipid soluble

B, C = water soluble

Front 10

Bohr Effect

Back 10

shift of the Hb binding curve to the right due to increased temperatures, H+ concentration, CO2 (HCO3-) concentration-- in systemic tissues

Front 11

blood clotting mechanism

Back 11

cut --> thrombopoeitin release + Ca2+ and Vitamin K --> converts prothrombin --> thrombin --> converts fibrinogen --> fibrin --> forms clot

Front 12

humoral immunity

Back 12

B lymphocytes, originate in Bone marrow.

1) plasma cells, primary response: produce antibodies /immunoglobulins (IgM, IgA, IgD, IgG, IgE)
2) memory cells: secondary response

Active immunity achieved via antibody production following vaccination.

Passive immunity achieved following natural infection.

Front 13

point mutation

Back 13

one base switched for another

Front 14

frame shift

Back 14

addition/deletion of one base

Front 15

transposon

Back 15

mobile piece of DNA, if inserted can cause mutation

Front 16

missense

Back 16

substitute one amino acid for another

Front 17

nonsense

Back 17

premature stop codon. Think NO = STOP!

Front 18

helicase

Back 18

unwinds dsDNA

Front 19

SSB proteins

Back 19

single strand binding proteins, stabilize ssDNA

Front 20

topoisomerase

Back 20

prevents "supercoiling of DNA" by breaking and reattaching strands

Front 21

blood type

Back 21

codominant system:

1) A has A antigens and anti-B antibodies
2) B has B antigens and anti-A antibodies
3) AB (universal recipient) has A and B antigens, no antibodies
4) O (universal donor) has no antigens but A and B antibodies

Rh+ = has Rh factor: during pregnancy, an Rh- mother can develop anti-Rh antibodies = bad for a 2nd Rh+ baby.

Alleles: IA, IB, i

Front 22

recombination frequency

Back 22

=genetic mapping units. The closer two alleles are, the less likely they are to recombine

Front 23

oligodendrocyte

Back 23

a type of glial cell that produces myelin in the CNS

Front 24

Schwann cells

Back 24

a type of glial cell that produces myelin in the PNS

Front 25

cell-mediated immunity

Back 25

T cells, produced in the thymus.

1) cytotoxic T cells- direct attack

2) helper T cells- regulate other T and B cells

Front 26

interferon

Back 26

protein produced by cells under viral attack-- diffuse to other cells and prevent spread of virus

Front 27

lymphatic system

Back 27

transports excess interstitial fluid (lymph) to keep fluid levels in body constant.

Lymph nodes = swellings along lymph vessels, contain phagocytic cells (leukocytes) that filter lymph and remove/destroy foreign particles

Front 28

functions of the liver

Back 28

regulate blood glucose levels (insulin/glucagon), process nitrogenous wastes (amino acids --> hepatic portal vein --> deamination --> ammonia --> urea), detoxification, store iron and Vitamin B12, destroy old RBCs, make bile and other blood proteins, defense, and beta-oxidation of fatty acids to ketones

Front 29

ADH/vasopressin

Back 29

produced in the hypothalamus and stored in the posterior pituitary, increases water absorption, inhibited by alcohol/caffeine

Front 30

adrenal cortex

Back 30

produces aldosterone (increases Na+ absorption and water absorption by osmosis), regulated by renin-angiotensin system.