Muscle Contraction

Question 1

How do sarcomeres contract?

Answer 1

• Myosin and actin slide over each other.

Question 2

What happens to the I-band and H-zone when contraction occurs?

Answer 2

• H-zone gets shorter.
• I-band gets shorter.

Question 3

What happens to the sarcomeres when the muscle relaxes?

Answer 3

• Returns to the original length.

Question 4

What’s the role of tropomyosin in the resting muscle?

Answer 4

• Blocks the myosin head from binding to actin-myosin binding site.

Question 5

Why does tropomyosin affect the muscle contraction?

Answer 5

• Prevents myofilaments from sliding past one another.