Question

During an action potential,what is the role of calcium?

• A. The calcium binds to the actin and myosin and makes them work together.
• B. The calcium causes the release of acetylcholine.
• C. The calcium removes the tropomyosin block.
• D. The calcium breaks apart ATP to ADP and P.

Answer 1

The correct option is B

The calcium causes the release of acetylcholine.

Nerve impulses also known as action potentials travel from the brain or the spinal cord to trigger the contraction of skeletal muscles. Muscles require innervation to function(Neuromuscular junction). Synaptic transmission at the neuromuscular junction begins when an action potential reaches the presynaptic terminal of a motor neuron, which activates voltage dependent calcium channels to allow calcium ions to enter the neuron. Calcium ions bind to sensor proteins on synaptic vesicles, triggering vesicle fusion with the cell membrane and subsequent acetylcholine release from the motor neuron into the synaptic cleft.