task 3

Question 1

describe all the phases in the muscle contraction

Answer 1

1. AP reaches the muscle= myoplasmic Ca2+ conc. increase.
2. calcium binds to troponin C complex on the actin
3. on the actin, tropomyosin- troponin shifts to the groove of actin filaments
4. myosin-binding site on the actin is now free to react with the myosin
5. myosin heads are changed from 90 degree to 40 degree
6. ADP+ Pi released - 45 degree
7. sliding filament
8. ATP bind again to the myosin
9. relaxation- 90 degree

Question 2

what is the “latency period”?

Answer 2

the time period between the stimulation and the start of the contraction. the process occurring during the latency period is called electromechanical coupling

Question 3

how to elicit muscle contraction

Answer 3

by a single supramaximal stimulus (one stimulus that causes fully contraction)