Which event occurs during skeletal and cardiac muscle contraction?
A) The distance between Z lines increases.
B) The sarcomeres lengthen.
C) The width of the H zone increases.
D) The width of the I band increases.
E) The area of actin and myosin overlap increases.

Question

Quizplus · Accepted Answer

During skeletal and cardiac muscle contraction, the area of actin and myosin overlap increases, which causes the sarcomeres to shorten and generate tension. This is known as the sliding filament theory of muscle contraction. The other choices are incorrect because the distance between Z lines and the width of the I band actually decrease during contraction, while the width of the H zone decreases rather than increases. Sarcomeres also do not lengthen during contraction.

Which Event Occurs During Skeletal and Cardiac Muscle Contraction