MT1

Question 1

what is pharmacodynamics?

Answer 1

what the drug does to the body

Question 2

what is pharmacokinetics?

Answer 2

what the body does to the drug

Question 3

what is affinity?

Answer 3

tenacity by which a drug binds to a receptor

Question 4

what is efficacy?

Answer 4

strength of agonist-receptor mechanism and resulting transduction mechanisms in eliciting a response

Question 5

what are the intracellular and extracellular concentrations of sodium ions?

Answer 5

intra -> 5-15mM
extra -> 140-145mM

Question 6

what are the intracellular and extracellular concentrations of potassium ions?

Answer 6

intra -> 140mm
extra -> 4.5mM

Question 7

what are the intracellular and extracellular concentrations of calcium ions?

Answer 7

intra -> 100nM
extra -> 1.25mM

Question 8

what are the intracellular and extracellular concentrations of hydrogen ions?

Answer 8

intra -> 10^-7.2M
extra -> 10^-7.4M

Question 9

what are the intracellular and extracellular concentrations of chloride ions?

Answer 9

intra -> 5-50mM
extra -> 120mM

Question 10

what are the intracellular and extracellular concentrations of HCO3- ions?

Answer 10

intra -> 15mM
extra -> 24mM

Question 11

what is tonicity?

Answer 11

osmotic force exerted by a solution

Question 12

what is taken as evidence of active transport?

Answer 12

accumulation of a substance above the level predicted at electrochemical equilibrium

Question 13

why are epithelial cells considered ‘polarised’?

Answer 13

two membranes with different properties

allows them to perform vectorial fluxes for absorption and secretion

Question 14

why is chemical transmission used at a synapse rather than direct electrical coupling?

Answer 14

impedance matching -> muscle cell is too large, so has too high capacitance for presynaptic current

Question 15

what is the structure of an ACh receptor?

Answer 15

five proteins in a barrel shape
two alpha, one beta, delta, gamma
not selective - any cation

Question 16

what are the three options for a synaptic vesicle after exocytosis?

Answer 16

kiss and stay
kiss and run
return to endosome

Question 17

what is the ‘kiss and stay’ mechanism of a synaptic vesicle?

Answer 17

after exocytosis, vesicle remains docked at the membrane where it is refilled

Question 18

what is the ‘kiss and run’ mechanism of a synaptic vesicle?

Answer 18

after exocytosis, pore quickly closes, then vesicle dislodges from the membrane, is reacidified and refilled

Question 19

what is the ‘return’ mechanism of a synaptic vesicle?

Answer 19

after exocytosis, it is acidified and returned to the endosome to be recycled

Question 20

what is a SNARE?

Answer 20

soluble NSF attachment receptor

Question 21

what are the four SNARES at a neuromuscular junction?

Answer 21

T -> SNAP-25, syntaxin
V -> synaptobrevin, synaptotagmin

Question 22

what is the function of the SNAREs?

Answer 22

intertwine to form complex that pulls vesicle to dock at membrane (V attaches to T)

Question 23

what is the difference between V-SNAREs and T-SNAREs?

Answer 23

V -> on the vesicle

T -> on the membrane, ‘targets’ for V-SNAREs

Question 24

which SNAREs intertwine with one another?

Answer 24

synaptobrevin to syntaxin

Question 25

what is complexin?

Answer 25

binds to the SNARE complexes, prevents premature fusion

Question 26

what dislodges complexin?

Answer 26

calcium ions

Question 27

what does botulinum do to the neuromuscular junction?

Answer 27

prevents ACh release, targets SNAREs
from clostridium botulinum bacteria