AAMC FL 3 B/B

Question 1

osmotic pressure

Answer 1

the minimum pressure which needs to be applied to a solution to prevent the inward flow water across a semipermeable membrane

Question 2

osmotic pressure equation

Answer 2

Question 3

If solute concentration is relatively HIGH, then osmotic pressure is _____

Answer 3

HIGH

Question 4

If solute concentration is relatively LOW, then osmotic pressure is _____

Answer 4

LOW

Question 5

oxidoreductase enzyme

Answer 5

enzymes that catalyze the transfer of electrons from one molecule to another molecule

catalyze redox reactions

Question 6

lyase enzyme

Answer 6

catalyzes the breaking of various chemical bonds by means other than hydrolysis and oxidation

Question 7

isomerase enzyme

Answer 7

convert a molecule from one isomer to another

catalyze a structural rearrangement

Question 8

hydrolase enzyme

Answer 8

use water to break a chemical bond, which typically results in dividing a larger molecule into smaller molecules

they catalyze hydrolysis

Question 9

protease enzyme

Answer 9

break apart peptide bonds via hydrolysis

a subtype of hydrolases

Question 10

primary vs secondary active transport

Answer 10

primary → directly pumps ions in or out using ATP

secondary → utilizes the gradient produced by a primary pump to drive transport

Question 11

NADH dehydrogenase complex #

Answer 11

complex I

Question 12

succinate dehydrogenase complex #

Answer 12

complex II

Question 13

cytochrome C reductase complex #

Answer 13

complex III (3)

Question 14

cytochrome C oxidase complex #

Answer 14

complex IV (4)

Question 15

how are work and speed related?

Answer 15

they are NOT

work = force x distance

POWER = work / time

Question 16

work (moving an object)

Answer 16

force x distance

(technically FDcosθ if there is an angle between these 2 vectors)

Question 17

purine vs pyrimidine

Answer 17

purines → 2 rings / larger

pyrimidines → 1 ring / smaller

Question 18

guanine → (purine or pyrimidine) ?

Answer 18

purine

Question 19

adenine → (purine or pyrimidine) ?

Answer 19

purine

Question 20

cytosine → (purine or pyrimidine) ?

Answer 20

pyrimidine

Question 21

thymine → (purine or pyrimidine) ?

Answer 21

pyrimidine

Question 22

uracil → (purine or pyrimidine) ?

Answer 22

pyrimidine

Question 23

which nucleotide pair is stronger, A – T or G – C ?

Answer 23

G – C

(3 H-bonds)

Question 24

high osmolarity means _____

Answer 24

high solute concentration

Question 25

DNA replication: **primase**

Answer 25

synthesizes the **short RNA primer** to start replication (once on the leading strand and continuously on the lagging strand)

Question 26

DNA replication: ligase

Answer 26

seals the ends of the DNA molecules together, creating one continuous strand of DNA

Question 27

DNA replication: **helicase**

Answer 27

**unwinds/separates** the DNA

Question 28

DNA replication: **topoisomerase**

Answer 28

**introduce negative supercoils** to alleviate torsional stress and reduce risk of strand breakage prevents recoiling

Question 29

DNA replication: **polymerase III**

Answer 29

synthesize the new daughter strands by adding complementary nucleotide bases to the parent strands (add in a 5' to 3' direction)

Question 30

DNA replication: **polymerase I**

Answer 30

replaces RNA primer with DNA nucleotides

Question 31

direction of DNA replication

Answer 31

5' to 3' (new strand)

Question 32

calcium involvement in muscle contraction

Answer 32

calcium binds to troponin which causes conformational change in tropomyosin, revealing the myosin binding site for the myosin head to bind to the actin/thin filament

Question 33

ATP role in muscle contraction

Answer 33

binding of ATP releases the myosin head from the actin/thin filament then when ATP hydrolyzes to ADP + Pi, the myosin head shifts back to its original position ready to bind again

Question 34

muscle contraction steps

Answer 34

calcium binds to troponin causing shift in tropomyosin to revela myosin binding site myosin binds to actin and the power stroke occurs as ADP + Pi dissociate from myosin ATP binds to myosin to release it from actin ATP hydrolyzes to ADP + Pi to recycle myosin head to resting position

Question 35

histone acetylation vs deacetylation

Answer 35

**acetylation →** unwinding, increases transcription and expression of genes **deacetylation** → tighter associations with histones; decreases transcription and expression of genes

Question 36

epinephrine vs norepinephrine

Answer 36

aka "adrenaline" and “noradrenaline” epinephrine → secreted from the adrenal medulla to act as a hormone norepinephrine → acts locally as neurotransmitter

Question 37

epinephrine and norepinephrine functions

Answer 37

the primary neurotransmitters of the sympathetic nervous system (fight-or-flight) involved in alertness and wakefulness

Question 38

microtubules

Answer 38

made of tubulin largest diameter transport substances within the cell (using motor proteins like kinesin and dynein) form mitotic spindle, cilia, and flagella

Question 39

microfilaments

Answer 39

made of actin → “actin filaments” involved in gross movement of the cell from within (ex. cleavage furrow or amoeba movement) dynamic → lengthen and shorten easily vs actin polymerization and depolymerization

Question 40

intermediate filaments

Answer 40

made of many types of protein (keratin, desmin, etc.) provide structural support / resist mechanical stress permanent rather than dynamic → rarely lengthen/shorten often

Question 41

restriction enzyme sequences must be \_\_\_\_\_\_\_\_

Answer 41

palindromic! when copied, both strands of DNA will have the same sequence when read 5′ to 3′

Question 42

how many base pairs do restriction enzymes cut?

Answer 42

4-8

Question 43

genomic imprinting

Answer 43

an epigenetic phenomenon that causes genes to be expressed or not, depending on whether they are inherited from the mother or the father via _methylation_ to guide expression

Question 44

polypeptide synthesis occurs in the _____ direction

Answer 44

N terminus (first) to C terminus (last)

Question 45

retroviruses

Answer 45

carry RNA and reverse transcriptases the enzymes convert the viral RNA to DNA which can then be integrated into the host genome for long term infection

Question 46

the descending loop of henle is permeable to \_\_\_\_\_\_\_

Answer 46

water only

Question 47

the ascending loop of henle is permeable to \_\_\_\_\_\_\_

Answer 47

salts (Na+, Cl-, K+, etc.)

Question 48

the optimal temperature for MOST enzymes is \_\_\_\_\_

Answer 48

37 C (body temp)

Question 49

what type of cells secrete mucus?

Answer 49

goblet cells (a type of epithelial cell)

Question 50

connective tissue

Answer 50

supports, protects, and gives structure to other tissues and organs in the body blood, fat, bone, cartilage, lymph, etc,

Question 51

smooth muscle vs skeletal muscle

Answer 51

**smooth muscle** → involuntary control (ex. heart) **skeletal muscle →** voluntary control (think “connected to skeleton”; ex. biceps)

Question 52

functions of small and large intestine

Answer 52

small → digestion and absorption of nutrients large → absorption of water and salts

Question 53

competitive vs noncompetitive vs uncompetitive inhibitors

Answer 53

**competitive →** bind to the enzyme active site (same site as substrate) **noncompetitive →** bind to a site other than the active site; bind equality well to the enzyme and enzyme-substrate complex **uncompetitive** → bind only to the enzyme-substrate complex

Question 54

osteoblasts

Answer 54

cells that make bones synthesize bone matrix and coordinate the mineralization of the skeleton

Question 55

osteoclasts

Answer 55

responsible for the breakdown of bone | (to release calcium?)

Question 56

osteocytes

Answer 56

these are osteoblasts that lie within the substance of fully formed bone involved in cell communication and mechanical sensing maintain bone mass