Question

If the skeletal muscle cell did experience an action potential, what would be the result?

a. sodium would be released from the sarcoplasmic reticulum
b. calcium would be released from the sarcoplasmic reticulum
c. actin heads would bind to myosin filaments, pulling them towards the M-line
d. myosin heads would bind to actin filaments, pulling them towards the M-line

Answer 1

The correct answer is option b. The correct answer is calcium would be released from the sarcoplasmic reticulum. When a skeletal muscle cell experiences an action potential, it triggers the release of calcium ions (Ca²+) from the sarcoplasmic reticulum (SR), which leads to muscle contraction.

Step-by-step explanation:

The correct answer is b. calcium would be released from the sarcoplasmic reticulum.

When a skeletal muscle cell experiences an action potential, it triggers the release of calcium ions (Ca²+) from the sarcoplasmic reticulum (SR). The calcium ions then bind to troponin, causing a conformational change in the sarcomere. This change allows the interaction of the thick (myosin) and thin (actin) filaments, leading to muscle contraction.

The sequence of events in skeletal muscle contraction is known as excitation-contraction coupling. It starts with the generation of an action potential, followed by calcium release and subsequent interaction between myosin and actin filaments.