Muscles work in pairs,because
A) contracted muscle cannot stretch itself back out again.
B) stretched muscle cannot contract by itself.
C) actin is located in one muscle of the pair,and myosin is in the other.
D) myofibrils of the paired muscles are connected.

Question

Quizplus · Accepted Answer

Muscles work in pairs because when one muscle in the pair contracts, the other muscle must relax or stretch in order for movement to occur. If both muscles in the pair were to contract simultaneously, the joint wouldn't move. Therefore, muscles in pairs must work in opposite directions, leading to one muscle contracting while the other relaxes or stretches.

Muscles Work in Pairs,because