Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

My MCAT Cards > Biology > Flashcards

Biology Flashcards

1
Q

microfilaments

A
  • ACTIN (use myosin + ATP for movement)
  • also in cytokinesis to contract cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

microtubules

A
  • hollow polymers of tubulin
  • uses kinesin + dynein to carry vesicles in cell
  • cilia/flagella = in eukaryotic motile cells
  • centrioles = in centrosome, organizing centre for microtubules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

intermediate filaments

A
  • cell-cell adhesion, integrity, resist tension, anchor
  • ketatin, lamin, desmin, etc.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

archaea

A
  • single cells, look like bacteria but eukaryotic function
  • circular chromosome, binary dfission
  • eukaryotic: wrap DNA with actual histones, begin with Met, RNA polymerase same
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

types of bacteria metabolism

A

obligate aerobes
obligate anaerobes
facultative anaerobes
aerotolerant aerobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

3 types of bacterial genetic recombination

A

transformation = integrate foreign DNA with plasmids
conjugation = mating (donor, female)
transduction = need VECTOR, virus transports DNA/RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

positive sense VS negative sense viral genome

A

positive sense = ssRNA directly translated
negative sense = ssRNA make complementary strand first (RNA replicase)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

viral life cycle:

A
  1. infection
  2. translation/assembly
  3. progeny release
    lytic (virulent) VS lysogenic (dormant, integrate provirus into genome)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

prions

A

nonliving infectious proteins
convert alpha helix > beta sheet, protein aggregates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

viroids

A

small pathogens living in plants, bind RNAs + silence genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

cell cycle overview

A
  • G1 = least amount of DNA, increase size, grow organelles
  • G1/S checkpoint = make sure DNA good to replicate p53
  • S = replicate DNA ploidy doesn’t change, 2n»2n
  • G2 = more growth
  • G2/M checkpoint = ensure all organelles, cytoplasm, correct DNA replication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

mitosis vs meiosis

A
  • 2n>2n VS 2n>n
  • meiosis I similar to mitosis, but meiosis II very different
  • crossing over in meiosis
  • homologous chromosomes pair in meiosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

nondisjuction in meiosis I

A

causes two n-1 cells and two n+1 cells
all 4 gametes abnormal ploidy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

nondisjunction in meiosis II

A

only 2 gametes affected, 2 normal
one n-1, one n+1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

order of sperm flow

A

SEVE(N) UP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

oogenesis

A
  • each oogenia = ONE functional oocyte
  • primary oocytes born with 2n, arrested in prophase I (meiosis)
  • during ovulation, meiosis I –> secondary oocyte (n) –> fertilization –> meiosis II
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

2 layers of oocyte

A

zona pelucida = surrounding oocyte, proteins + compounds
corona radiata = surrounding cells, attached to oocyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

male sexual development

A
  • androgens during fetal period causes male sexual differentiation
  • testosterone = develops reprod. system and secondary sex characteristics
  • FSH stimulates sperm maturation
  • LH causes testosterone production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

female sexual development

A
  • estrogen secreted due to FSH, secondary sex charaxcteristics
  • estrogen regenerates uterine lining, but progesterone (secreted by corpus luteum) maintains it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

menstrual cycle:

A
  1. follicular phase = GnRH releases LH/FSH, develops follicles, estrogen thickens lining
    2. ovulation = LH PEAK
  2. luteal phase = released follicle forms corpus luteum, secretes PROgesterone to develop lining – high est/progest = low LH/FSH
  3. menstruation = high progesterone buildup causes low LH, uterine layer shed, corpus luteum no longer to secrete est/progest, so causes GnRH to be stimualted again (low LH = corpus luteum lost)
  4. pregnancy = blastocyst releases hCG (analog of LH) that maintains corpus luteum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

cortical reaction

A

after sperm penetrates egg, relese of Ca+ ions
depolarizes egg membrane to prevent another sperm, increases metabolic rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

blastocyst

A

ICM (becomes organism) and trophoblast (placenta)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

gastrulation: 3 primary germ layers

A
  • ectoderm = NS, hair, skin, nails
  • mesoderm = support structures, muscle, bone, excretory, circulatory, gonads
  • endoderm = epithelial linings, pacreas, thyroid, bladder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

fetal circulation

A
  • fetal arteries = DEOX blood from fetus to placenta
  • fetal veins = OX blood from placenta to fetus
  • gas exchange occurs at the placenta
  • don’t want baby’s blood and mothers to mix
  • detoxification by mother’s liver, nutrient/waste exchange at placenta
  • 3 shunts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

fetus: 3 shunts to direct blood away from its organs

A
  1. foramen ovale RA-LA = blood skips Right ventricle to bypass lungs, directly into body
  2. ductus arteriosus = shunts blood in pulmonary artery to aorta
  3. ductus venosus = shunts blood from placenta (umbillical vein) to inferior vena cava (bypass liver)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

3 trimesters: overview

A
  1. heartbeag 22 days, 8 weeks = fetus, organ systems made
  2. growth, moves
  3. growth, LESS movement, antibodies transferred
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

specific neuroglia

A
  • support / defense / immune system
  • astrocytes = BBB
  • microglia = break down waste products
  • oligodendrocytes (CNS) and schwann cells (PNS)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

action potential notes

A
  • resting potential = -70mV (inside)
  • cells = salty bananas
  • Na+/K+ ATPase = “pumpKin” to restore balance
  • axon hillock = threshold, trigger zone, voltage gated Na+ channels open
  • hyperpolarization = refractory period prevents another signal
  • local anesthetics block Na+ channels preventing pain impulses
  • end of axon, Na+ channels open, Ca+ rushes in, NT vesicles released, enter synapse
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

reflex arc

A
  • only processing at spinal cord level
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

peptide hormones

A
  • bind EXTRACELLULAR, trigger cAMP signalling cascade
  • end in “in” “ine”
  • rapid but short-lived
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

steroid hormones

A
  • bind INTRACELLULAR receptors
  • cholesterol-based, cross membrane
  • “one” “oid”
  • slower but long-lived
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

AA hormones

A
  • unpredictable
  • catecholamines = fast lived, short lived (peptide-like)
  • T3/T4 = slow onset, long lived (like steroid)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

tropic hormones

A

stimulate production of another hormone by another gland that acts on a tissue, eg. ACTH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

pituitary gland

A
  • anterior = vascular connection (HTHPP): GH, TSH, FSH, LH, ACTH, PRL
  • posterior = neural connection (tract): store + release oxytocin + ADH from hypothal.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

thyroid

A
  • controlled by TSH, T3/T4 = metabolism
  • calcitonin = tones down Ca+
  • PTH = increases Ca+
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

3 types of corticosteroids in adrenal cortex (sugar, salt, sex)

A
  1. glucocorticoids = cortisol (raise blood sugar)
  2. mineralocorticoids = aldosterone (increase Na+/H2o reabsorption to increase BV and BP)
  3. corticak sex hormones = androgens/estrogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

aldosterone pathway

A
  • low BP sensed by juxtaglomerular cells
  • cells secrete RENIN – celaves angiotensin to angiotensin I
  • ACE converts angiotensin I to angiotensin II
  • angiotensin II stmulates adrenal cortex to release aldosterone to increase BP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

adrenal medulla

A
  • ectoderm, NS, fast acting, not essential for life
  • catecholamines (E, NE) – sympathetic fight/flight
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

pancrease cells

A

alpha = glucacon
beta = insulin (destroyed in type I, low receptor sensitivity in type II)
delta = somatostatin (inhib. both insulin + glucagon), reelesed by high BG/AA’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

pineal gland

A

secretes melatonin
circadian rhythms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

EPO

A

released by kidneys
production of RBC’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

ANP

A

released by the heart
regulates salt/water balance
promotes excretion, deceases BV and BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

types of steroid hormones: list

A
  • cortical hormones (all)
  • testosterone, estrogen, progesterone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

types of AA hormones: list

A
  • T3/T4
  • any other hormone is a PEPTIDE hormone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

diaphragm is under ____ control

A

somatic control
but breathing is autonomic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

surfactant

A

on alveoli
REDUCES surface tension
prevents collpase of alveoli during exhalation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

negative pressure breathing

A

diaphragm contract, pulls downwards, increase V, decrease P, air sucked in from low pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

total lung capacity

A

max volume of air in lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

residual volume

A

air left in lungs after complete exhalation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

vital capacity

A

air volume inhaled/exhaled in normal breath = tidal voume
VC = tidal volume + expiratory/inspiritory reserve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

expiratory/inspiritory reserve

A

additional air forced out/inhaled

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

heart: blood flow order

A

vena cava > RA > tricuspid > RV > pulm valve > pulmonary A > lungs > pulmonary V > LA > bicuspid/mitral > LV > aortic valve > aorta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

heart sounds

A

1st pump: AV valves close – RV contracts = pulmonary circulation
2nd pump: semilunar valves close – LV contracts = systemic circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

electrical conduction in heart: order

A

SA node > AV node > bundle of His > purjunke fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

cardiac output

A

CO = SV x HR
volume / min = (volume / beat) x (beats/min)

56
Q

v-tach

A

heart beats too fast, cannot fill with blood, systemic pressure drops, no blood pumped

57
Q

3 types of blood cells

A
  1. erythrocytes (RBCs) = EPO stimulates
  2. leukocytes (WBCs) – 5 types, granular vs agranular
  3. thrombocytes (platelets) = thromopietin stimulates
58
Q

myogenic

A

no neurological input required
eg. HEART beating

59
Q

granular leukocytes

A

neutrophils
eosinophils
basophils

60
Q

agranular leukocytes

A

lymphocytes = B & T cells, mature different locations
monocytes = macrophages

61
Q

blood typing

A
  • blood type = which surface antigens your cells have, produce antibodies against what you don’t have
  • AB = both antigens, NO antibodies (universal recipient)
  • O = neither antigen, BOTH antibodies (universal donor)
  • Rh factor = absence/presence of D allele, pregnancy issues for SECOND CHILD
62
Q

blood pressure

A
  • BP = gauage pressure (pressure above atmospheric)
  • systolic = ventricular contraction, diastolic = ventricular relaxation
  • pressure highest in aorta, largest drop in arterioles
  • **ΔP = CO x TPR ** same as V = IR where ΔP is presure change in circulation (force), CO is current of blood, and total peripheral resistance (blood vessels = resistors)
  • add more capillary beds in PARALLEL = decrease resistance total
  • high resitance if longer and narrower vessels
63
Q

hemoglobin dissociation curve

A
  • hemoglobin = coopertive binding = s shaped curve
  • “exercise is RIGHT”
  • right shift = decrease affininty for O2 = favours unloading of O2 (in exercise) – high temp, high CO2, low pH shift RIGHT
  • left shift = increase affinity for O2 = favours loading of O2 (eg. fetal hemoglobin)
64
Q

CO2 in the blood

A
  • CO2 travels as bicarbonate anion in the blood (SOLUBLE)
  • CO2 + H2O = H2CO3 = H+ + HCO3-
65
Q

hydrostatic vs osmotic pressure

A

hydrostatic pressure = PUSH = force of blood in vessels from heart, drops as fluid moves out of capillary
osmotic pressure = PULLS in = number of particles dissolved in plasma, if stays thre same, hydrostatic drops below osmotic and net flux of H20 IN

66
Q

blood clotting

A

damaged vessel exposes collagen
thrombin is made, produces fibrin
fibrin forms net to catch RBCs
clot broken down by plasmin

67
Q

complement system

A

nonspecific, proteins in blood
activated through antibody activation or without antibodies

68
Q

interferons

A

if a cell gets infected by a virus, produces interferons
lowers permeability of nearby cells to protect them
increases MHC II molecules (extracellular)

69
Q

MHC I / MHC II

A

MHC I = in all cells, for endogenous antigens (eg. virus)
MHC II = only on special APC’s for exogenous antigens (eg. bacteria)

70
Q

macrophages

A

engulf + consume pathogens
MHC II

70
Q

mast cells

A

release histamine
promote inflammation
ALLERGENS

71
Q

NK cells

A

detects downregulation of MHC
destroys body’s own infected cells

72
Q

dendritic cells

A

APC’s, present antigens to adaptive cells T/B

73
Q

granulocytes

A

neutrophils, eosinophils, basophils
inflammatory response

74
Q

cytokines and chemokines

A

cytokines = induce INFLAMMATION
chemokines = attract immune cells to site

75
Q

B cells

A
  • humoral immunity, mature in BM, exposure in lymph nodes
  • plasma B cells = produce antibodies, tag cells for killing
  • memory B cells = stay in lymph nodes
76
Q

T cells

A
  • cell-mediated immunity, mature in thymus
  • CD4/MHC II - extracellular - HELPER T Cells (secrete lymphokines)
  • CD8/MHC I - intracellular - CYTOTOXIC T Cells (inject toxic chemicals)
76
Q

extracellular infection: process

A
  • macrophages engulf bacteria, present bacterial antigens on MHC II, release cytokines
  • cytokines attract inflammatory cells, mast cells release histamine, increase leakiness of blood vessels
  • dendritic cells leave tissue to lymph node, presents antigens to B cells
  • make plasma + memory B cells
  • antibodies tavel to tissue, tag bacteria for destruction
  • dendritic cells also activate helper T cells (recognize MHC II on APC’s)
77
Q

intracellular infection: process

A
  • infected cells produce interferons to protect nearby cells
  • begin presenting viral proteins on MHC I
  • CD8 recognizes MHC I antigens, injects toxin to kil
  • if MHC gets downregulated by virus, NK cells detect this change
78
Q

autoimmunity

A
  • all cells in body express “self antigens” to signal immune cells not to attack
  • autoimmunity where cells expressing self-antigens get attacked (eg. Beta cell destruction in T1D)
  • can also have hypersensitivity to some foreign antigens (allergies!!!)
78
Q

ADH and aldosterone trigger:

A

thirst

79
Q

glucagon and ghrelin trigger

A

hunger

80
Q

leptin & CCK trigger

A

satiety

81
Q

enteropeptidase

A

master switch, secreted by duodenum
enteropeptidase activaqtes trypsin, which activates chemotrypsin and carboxypeptidase

82
Q

brush border enzymes

A

most of the enzymes to break down di/tri/ biomolecules
enzymes for carbs, proteins, and lipids found here
DUODENUM lining

83
Q

pancreas exocrine function

A

acinar cells make pancreatic juice, ezymes for all 3 molecules
pancreatic amylase, peptidases (trypsin, chemotrypsin, carboxypeptidase), lipase
all function in the duodenum

83
Q

3 components in bile

A
  1. bile salts (like soap – polar + nonpolar) emulsify fats to allow lipase to break them down (lipase is polar!)
  2. pigments
  3. cholesterol
84
Q

absorption of simple sugars and AA

A

absorbed by facilitated diffusion / active transport into epithelial cells
blood usescountercurrent multiplication to max absorption
cabrs + AA’s diffuse into capillaries, into liver via HPV

85
Q

absorption of short chain fatty acids

A

follow the same path as sugar/AA’s – diffuse into capillaries
do not require transporters since nonpolar

86
Q

absorption of large fats/glycerol/cholesterol

A

pass into epithelial cells, reform into triglycerides
packaged into chylomicrons – enter lymphatics via lacteals, to thoracic duct

87
Q

absorption of vitamins

A

absorbed in small intestine
fat-soluble into chylomicrons
water-solubl follow AA/sugar into capillries

88
Q

starling forces

A

high hydrostatic pressure in glomerulus forces fluid into capsule even though osmotic pressure is high in blood, hydrostatic pressure is higher

89
Q

nephron structure

A
  • descending limb = only permeable to water
  • ascending limb = only permeable to salts
  • DCT = aldosterone (reabsorbs Na+ and H2O)
  • collecting duct = aldosterone + ADH (reabsorbs H2O)
89
Q

osmotic vs oncotic pressure

A

osmotic pressure = sucking that draws water in due to solutes
oncotic pressure = osmotic P due to PROTEINS specifically

90
Q

layers in the epidermins

A
  • come lets get sun burned (top-bottom)
    1. stratum corneum
    1. stratum lucidium (only in thick, hairless)
    1. stratum granulosum
    1. stratum spinosum
    1. stratum basale
91
Q

what’s found in epidermis

A
  • keratinocytes
  • langerhans cells (macrohpages)
  • stem cells
  • melanocytes (melanin)
92
Q

what’s found in dermis

A
  • sweat glands
  • hair follicles
  • blood vessels
  • sensory receptors
93
Q

what’s found in hypodermis

A

connective tissue
fat

94
Q

thermoregulation: hot VS cold

A
  • hot: sympathetic neurons, release of sweat, evap endothermic
  • cold: arrector pilli muscles contract, shivering uses ATP, brown fat = decouples ETC to make HEAT
95
Q

skeletal muscle: overview

A
  • striated
  • voluntary
  • somatic
  • MANY nuclei
  • not myogenic (need NS input)
  • red fibres, white fibres, sarcomere unit
96
Q

smooth muscle: overview

A
  • non striated
  • involuntary
  • autonomic
  • 1 nuclei
  • myogenic
97
Q

cardiac muscle: overview

A
  • striated
  • invountary
  • autonomic
  • 1-2 nuclei
  • myogenic
  • intercalated discs, gap junctions
  • sarcomeres like skeletal
98
Q

red fibres

A
  • skeletal muscle
  • red = SLOW twitch, HIGH myoglobin, oxidative phos. for ATP
  • contract SLOW but for SUSTAINED time
99
Q

white fibres

A
  • skeletal muscle
  • white. =FAST twitch, LOW myoglobin, glycolysis/fermentation for ATP
  • contract FAST but fatigue FAST
100
Q

Ca+ and muscle contraction

A
  • required for ALL MUSCLE contraction
  • stored in the sarcoplasmic reticulum
  • activated release by T-tubules
  • Ca+ binds to sites on troponin, causes tropomyosin to REVEAL myosin binding site on actin
101
Q

sarcomere structure

A
  • THICK = myosin
  • THIN = ACTIN + troponin bond to tropomyosin
  • A band length does NOT change during contraction
  • myofibrils = line of sarcomeres, surrounded by sarcoplasmic reticulum
102
Q

sarcolemma

A
  • cell membrane
  • dsitributes action potentials to all sarcomeres using T-tubules
103
Q

contraction STEPS: sarcomere

A
  1. neuromuscular junction, Ach released at synapse, binds receptors on sarcolemma = depolarized
  2. depolarization travels down T tubules to sarcoplasmic reticulum = Ca+ release
  3. Ca+ binds to troponin, changes tropomyosin to release myosin binding on actin
  4. myosin binds to actin (ADP state) – POWER stroke = RELEASE OF ADP, pulls filaments towards M line
  5. binding of ATP = release of myosin
  6. Ach degraded in synapse by enzyme, signal stops, Ca+ stops, binding sites covered, myosin binds ATP to release
104
Q

rigor mortis

A

dead, no ATP, cant bind to myosin, so myosin cannot dissociate from actin (needs ATP to release)
STIFF

105
Q

tetanus

A
  • both disease and condition
  • contractions so frequent that muscle cannot relax at all
  • toxin blocks GABA that inhibits neurons, constant stimulation
  • summation of muscle contractions until fatigue/failure
106
Q

bone

A
  • CT, mesoderm
  • compact VS spongy (cavities with bone marrow)
  • long bone: middle is diaphysis, ends are epiphysis
  • bony matrix = structural unit, osteons
  • most bones made by hardening of cartilage
107
Q

epiphyseal growth plate

A

site of longitudinal bone growth

108
Q

osteoblasts VS osteoclasts

A
  • osteoblasts = make bone, activated by calcitonin (released by thyroid when Ca+ is HIGH to tone down Ca+), osteoblasts make new bone to lower Ca+ levels in blood
  • osteoclasts = macrophage, resorb bone, stimulated by PTH to increase Ca+ levels in blood vitamin D promotes osteoclasts, which allows NEW bone to form
109
Q

hemizygous

A

only ONE allele (eg. males hemizygous for X alleles)

110
Q

penetrance

A

proportion of population with genotype that actually EXPRESSES it

111
Q

expressivity

A

different phenotypes of the same genotype

112
Q

griffith experiment

A
  • transformation in mice + bacteria
  • bacteria are capable of transferring genetic material = transformation
113
Q

hershey and chase

A
  • determined genetic info carried by nucelic acid by virus
113
Q

insertion mutations
translocation mutations

A

insertion = DNA segment moved into a new chromosome
translocation = DNA segment of one chromosome SWAPPED for another

114
Q

inborn errors of metabolism

A

defects in metabolism genes
eg. PKU = defect in Phe metabolism, cause toxic buildup

115
Q

genetic leakage

A

flow of genes between SPECIES

116
Q

genetic drift

A

founder effect
bottleneck

117
Q

recombination frequency

A

likelihood that 2 alleles are separated (low = likely linked)
= proportional to distance between genes

118
Q

hardy weinberg equilibrium

A
  • population large, no mutations, random mating, no migration
  • alleles: p + q = 1 (dominant allele + recessive allele = 1)
  • PHENOTYPES: p^2 + 2pq + q^2 = 1 (homoz. dom + hetero + homoz. recess = 1)
119
Q

genetic cross ratios:
PP x pp, Pp x Pp, Pp x pp

A

PP x pp = all Pp
Pp x Pp = 1 : 2 : 1 (PP:Pp:pp)
Pp x pp = 1 : 1 (Pp:pp)

120
Q

dihybrid cross ratios: both heterozygous

A

9 : 3 : 3 : 1

121
Q

x linked (sex)

A

men with trait CANNOT pass to their son
daughters are either carriers or have trait (if mother also affected)

122
Q

modes of natural selection

A
  • stabilizing selection = selects against extremes
  • directional selection = adaptive pressures favour ONE extreme
  • disruptive selection = favours BOTH extremes, not intermediate
123
Q

speciation

A

formation of new species by REPRODUCTIVE ISOLATION
= progeny cannot interpreed, pre and post zyogtic mechanisms

125
Q

structure of RBC

A
  • no membrane bound nucleus
  • no DNA
  • no organelles
  • just lots of hemoglobin
126
Q

what amino acids get phosphorylated

A

Serine (S)
Tyrosine (Y)
Threonine (T)

127
Q

mitochondrial DNA

A

inherited from MOTHERS
cytoplasmic DNA

128
Q

single crossover VS double crossover events

A
  • single crossover = affect only the ends of chromosome arms
  • double crossover = middle of chromosome affected – chromosomal arms of homologous chromosomes cross over in two different places along the arm, results in a section in the middle of each chromosome being exchanged
129
Q

analogous structures

A

Analogous structures are those structures that evolved independently to carry out the same function.

Thus, the wing of a bee and the wing of a bird are analogous structures.

130
Q

homologous structures

A

Homologous structures are those that have a similar evolutionary history, arising from the same source, even if they now have different functions.

The forelimbs of mammals (human arm, walrus flipper, bat wing) would all be homologous despite their different functions

131
Q

interneuron

A

intercommunication point for the afferent and efferent neurons within the CNS.
usually in spinal cord

132
Q

number of possible gametes:

A

X = # of possibilities for each gene (usually 2)
n = number of genes total

X^n eg. 3 genes ABC and they are heterozygous for each, 2^3 = 8 combinations

My MCAT Cards (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions