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Flashcards in BIology Deck (80):
1

divergent evolution

development of dissimilar characteristics in species with common ancestry

2

founder effect

genetic drift as result of small # of organisms starting a population

3

allopatric speciation

speciation as result of geographic separation of a population of organisms

4

directional selection

adaptive change in response to change in environment (ie. bugs and pesticides, bacteria and soap)

5

stabilizing selection

maintain uniform characteristics by eliminating deviation

6

Which hormones are high during ovulation (day 14/15)?

high LH, estrogen, and FSH

7

day of progesterone peak

day 21-22, helps with implantation

8

When are FSH and LH lowest?

immediately before menstruation

9

secretions of anterior pituitary (7)

secretes FLAT PEG
FSH, LH= stimulate gonads
ACTH= stimulate adrenal cortex
TSH= stimulate thyroid
Prolactin= stimulates milk
Endorphins= reduce pain
Growth Hormone= aid in growth

10

what does pancreas secrete? (2)

secretes insulin (decrease blood glucose) and glucagon (increase glycogen conversion to glycogen and storage)

11

what does parathyroid secrete? (1)

parathyroid hormone (increase Ca2+ in blood)

12

what does thyroid secrete? (2)

calcitonin (decrease Ca2+ in blood, promote Ca2+ into bone) and thyroxin (control basal metabolism)

13

function of descending loop of Henle

reabsorption of water

14

glomerulus function

filtration from circulation to nephron tubule, and block plasma protein from being filtrated

15

proximal convoluted tubule

reabsorb glucose and amino acids; secrete extra urea and metabolite

16

distal convoluted tubule

channels activated by aldosterone to actively reabsorb Na+ and water

17

Where is ADH/ vasopressin made and released? What does it do?

made in hypothalamus and released from posterior pituitary; increase water reabsorption in the collecting duct

18

aldosterone

released from adrenal cortex to increase Na+ in the distal convoluted tubule and increase blood volume

19

hypothalamus

regulates anterior pituitary via GnRH and secretes ADH and oxytocin

20

What happens in the thymus?

produce T-Cells--> activate B Cells --> produce antibodies and macrophage (immunoglobulins)

21

Macrophage

white blood cell derived from bone marrow

22

active immunity

production of antibody by patient (ie. vaccine)

23

passive immunity

injection of antibodies

24

What are the shapes of these bacteria: cocci, baccili, spirilla?

cocci= spherical, baccili= rod-shaped, spirilla= helical, spiral

25

systole

contraction of the heart/ pumping

26

diastole

relaxation of heart and filling with blood

27

Describe the flow of blood from body to the heart

vena cava --> right atrium --> right ventricle --> pulmonary artery --> lung alveoli --> pulmonary vein --> left atrium --> left ventricle --> aorta --> body

28

portal system

blood flow from an artery --> capillary bed --> vein --> secondary capillary bed --> 2nd vein (ie. hepatic from small intestine to liver, hypothalamic from hypothalamus to anterior pituitary)

29

flat bones

ribs, skull, vertebrae, pelvis; red bone marrow; used for protection

30

long bones

hand, feet, arms, leg; yellow bone marrow, used for locomotion

31

Which type of inhibition can be overcome by high concentration of substrate?

Competitive Inhibition

32

gustatory cell

cell involved in taste

33

What is special/different about erythrocytes?

erythrocytes have no DNA/ nucleus/ mitochondria because of hemoglobin, but they can still produce ATP

34

faculative aerobe

can survive under aerobic and anaerobic conditions

35

obligate anaerobe

dies under aerobic conditions

36

PGAL

end product of photosynthesis

37

anabolism

cellular reaction that makes a larger molecule from smaller ones and needs energy

38

catabolism

cellular reaction that breaks down large molecules into smaller ones and releases energy

39

How does hyperventilation affect pH?

hyperventilation causes decreased concentration of CO2 in blood = increased pH, alkolosis

40

action potential initiation

influx of Na+ into cell depolarizes, K+ flows out of the cell to repolarize

41

Which ions have high concentration outside the cell?

Na+, Ca2+, Cl-

42

Which ions have high concentration inside the cell?

K+

43

prophase

chromatin condense to chromosomes, spindle forms, nuclear membrane disappears, synapsis and crossing over occur

44

metaphase

homologous pairs line up at middle and attach to spindle

45

anaphase

pairs separate to opposite poles (disjunction)

46

telophase

nuclear membrane forms and cell divides

47

(S) phase

synthesis phase, interphase (G1-->S-->G2-->M)

48

disjuction

separation of homologous pairs (maternal and paternal chromosomes) during meoisis

49

What does distance between genes on a chromosome tell us?

distance between genes is proportional to percent recombination

50

indeterminate cleavage

division resulting in cells that maintain ability to develop into complete organism

51

How many ATP are produced by substrate phosphorylation of 1 glucose?

4 ATP (2 from glycolysis and 1 from each TCA cycle)

52

How many net ATP are produced by oxidative phosphorylation of 1 glucose?

36 ATP

53

primary structure

sequence of amino acids

54

secondary structure

twisting/folding (alpha helices and beta sheets)

55

tertiary structure

interactions of side chains (disulfide and hydrophobic/philic)

56

quaternary structure

interaction of 2 or more polypeptides

57

Do A-T or G-C bonds have higher boiling point?

G-C because they have 3 H-bonds whereas A-T bonds have 2 H-bonds

58

purines

A and G (pure As Gold)

59

pyrimidines

T, C, and U

60

semilogarithmic plot

one variable is in logarithmic scale and other variable is in linear scale

61

small intestine

site of chemical digestion and absorption of amino acids and monosaccharides (villi)

62

large intestine

absorb salt and water

63

sympathetic nervous system neurotransmitter

release NE and Epinephrine (fight or flight)

64

parasympathetic nervous system neurotransmitter

releases ACh (rest and digest)

65

transformation

DNA is transferred from one bacteria to another

66

transcription

mRNA synthesis from DNA template

67

translation

polypeptide chain is made from mRNA on ribosome

68

Factors that affect hemoglobin affinity for oxygen

acidity/ low pH= decreased affinity
increased CO2= decreased affinity
increased O2 in alveoli capillary= increased affinity (cooperation)

69

transamination

conversion of amino acid for entry to TCA cycle

70

lactic acid fermentation

carbohydrate metabolism during low oxygen to convert pyruvate to lactic acid and regenerate NAD+ so glycolysis can continue

71

sarcomere components

type of skeletal muscle fiber: thick filaments (myosin) and thin filaments (actin, tropomyosin, troponin)

72

Process of skeletal muscle contraction

Ca2+ is released into cytoplasm --> Ca2+ binds to troponin (thin) --> tropomyosin shifts to expose myosin binding sites --> myosin binds to actin --> contraction

73

bile (where is it made and what does it do?)

made by liver, secreted by gall bladder in response to CCK hormone to break up fats

74

hybridization

base pairing between complementary nucleic acid sequences

75

primary oocytes

all their mitotic divisions occur before birth

76

What kind of cells can produce ATP via ATP synthase?

Bacteria (in plasma membrane) and Humans (in inner mitochondrial membrane)

77

Peristalsis

radial contraction/relaxation of muscle that propagates like a wave (ie. smooth muscle of GI tract; earthworms)

78

What is the greatest limit to cell size?

Ratio of surface area to volume because cells need to be able to exchange things with the outside

79

What are the functions of the liver? (3)

detoxify poison, produce bile, facilitate fat absorption in small intestine by breaking down fat into smaller pieces

80

What types of muscle are striated?

skeletal and cardiac (NOT smooth)