Question

Place the following steps of muscle contraction in the order in which they occur.

a) Neuron stimulates a muscle cell
b) Ca2+ is released from the sarcoplasmic reticulum
c) Troponin moves tropomyosin protein
d) Action potential triggers opening of Ca2+ release channel

Answer 1

The correct order of steps in muscle contraction is: Neuron stimulates a muscle cell, Action potential triggers opening of Ca2+ release channel, Ca2+ is released from the sarcoplasmic reticulum, Troponin moves tropomyosin protein.

Step-by-step explanation:

1. Neuron stimulates a muscle cell
2. Action potential triggers opening of Ca2+ release channel
3. Ca2+ is released from the sarcoplasmic reticulum
4. Troponin moves tropomyosin protein

The process of muscle contraction begins with a neuron, which stimulates a muscle cell. This stimulation triggers an action potential, which then initiates the opening of Ca

2+

release channels. Ca

2+

is released from the sarcoplasmic reticulum and binds to troponin, causing tropomyosin to move and expose the actin-binding sites, leading to muscle contraction.