09-24-2018, 10:06 AM
did anyone take nbme 15 online? what is the official answer
many say it's C , but it should by tropomycin not troponin C
I think the answer is D, just like cardiac glycosides mechanism ( Na - Ca exchanger --> more NA influx = more ca efflux , thus less intracellular ca)
During an experiment of muscle contraction,intracellular ca is decreased after a substance is administered to a muscle preparation obtained from an experimental animal.Which of following best explains why contraction is inhibited in this case?
A.Ach release is increased
B.depolarization along T tubules is enhanced
C.myosin binding sites on actin remain covered by troponin c
D.na influx is increased
E.tropomyosin is deteched from actin.
many say it's C , but it should by tropomycin not troponin C
I think the answer is D, just like cardiac glycosides mechanism ( Na - Ca exchanger --> more NA influx = more ca efflux , thus less intracellular ca)
During an experiment of muscle contraction,intracellular ca is decreased after a substance is administered to a muscle preparation obtained from an experimental animal.Which of following best explains why contraction is inhibited in this case?
A.Ach release is increased
B.depolarization along T tubules is enhanced
C.myosin binding sites on actin remain covered by troponin c
D.na influx is increased
E.tropomyosin is deteched from actin.