Question

When a sarcomere contracts: Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a) the A band shortens b) the I band lengthens c) the Hzone shortens d) the zone of overlap remains unchanged

Answer 1

During muscle contraction, the H zone shortens and the I band lengthens. The A band does not shorten, but the zone of overlap increases as the thin filaments move inward.

Step-by-step explanation:

During muscle contraction, the H zone shortens and the I band lengthens. The A band does not shorten but the A bands of different sarcomeres move closer together, eventually disappearing. The zone of overlap increases as the thin filaments move inward. This is known as the sliding filament model of muscle contraction.