Steps initiating a muscle contraction

Question 1

Step 1

Answer 1

ACh released

Question 2

Step 2

Answer 2

Action potential reaches T tubule

Question 3

Step 3

Answer 3

Sarcoplasmic reticulum releases Ca2+

Question 4

Step 4

Answer 4

Active sites exposed and cross-bridges form

Question 5

Step 5

Answer 5

Contraction cycle begins