Given these events: 1) calcium ions move along their concentration gradient
2) action potential in cell membrane
3) opening of ion channels in sarcoplasmic reticulum
4) action potential in T tubules
5) actin to myosin cross-bridges form
Arrange them in the correct sequence as they participate during skeletal muscle contraction.
A) 1, 2, 5, 3, 4
B) 1, 5, 4, 3, 2
C) 2, 4, 3, 1, 5
D) 2, 1, 5, 3, 4
E) 5, 3, 4, 2, 1

Question

Quizplus · Accepted Answer

The correct sequence for events during skeletal muscle contraction starts with an action potential in the cell membrane (2), which then travels down the T tubules (4), leading to the opening of ion channels in the sarcoplasmic reticulum (3). This results in calcium ions moving along their concentration gradient into the cytosol (1), which then allows actin to myosin cross-bridges to form (5), enabling muscle contraction.

Given These Events: 1) Calcium Ions Move Along Their Concentration