Question

What is involved in a musclecontraction?A. Myofibrils in the muscle shorten and lengthen to makethe muscle contract and extend.B. Actin and myosin come in and out of the cell to make itthicker or thinner which changes its length.C. The gap junctions between the cells pull them closertogether which shortens the muscle.D. The extra nuclei trigger nerves to stiffen the musclesand make them shorter.

Answer 1

Okay, this process of muscle contraction is mainly given by the interactions between muscle fibers, known as actin and myosin, that gives the structure the potential to contract and relax, so changes in lengths occur. Being this, the answer is B. actin and myosin come in and out of the cell to make it thicker or thinner which changes its length.