Muscles

Question 1

Thick and thin filaments maintain their ___, wheter the muscle is relaxed or contracted.

Answer 1

Same length

Question 2

ACh is an acronym for ____

Answer 2

Acetylcholine

Question 3

Stages of Cross-bridge cycling in order

Answer 3

1) Calcium binds troponin; myosin binding site uncovered
2) Cross-bridge formation
3) Power stroke
4) Release of myosin head by ATP
5) Reset of myosin head

Question 4

When calcium ions bind to toponin, which of the following then occurs?

Answer 4

The myosin binding sites on actin are exposed

Question 5

The arribal of a nerve impulse at the synaptic knob of a motor neuron causes synaptic vesicles to relase _____ into the synaptic cleft.

Answer 5

Acetylcholine

Question 6

When a muscle fiber is in a relaxed state, the ____ molecules cover the G-actin active sites, preventing interaction between thick filaments and thin filaments

Answer 6

Tropomyosin

Question 7

4 steps at a neuromuscular junction

Answer 7

1) Arrival of nerve signal at synaptic knob
2) Calcium entry into synaptic knob
3) Exocytosis of ACh into synaptic cleft
4) Binding of ACh to motor end plate