Question

The force (mechanical event) exerted by a motor unit varies with ______

Answer 1

The force exerted by a motor unit varies with the number of motor fibers it innervates. Smaller motor units are activated first, resulting in a relatively small degree of contractile strength. As more strength is needed, larger motor units with bigger motor neurons are enlisted, leading to a progressively stronger muscle contraction.

Step-by-step explanation:

The force exerted by a motor unit varies with the number of motor fibers it innervates. In skeletal muscles, the recruitment of motor units plays a crucial role in regulating muscle contraction and force generation. The nervous system activates smaller motor units first, which results in a relatively small degree of contractile strength. As more strength is needed, larger motor units with bigger motor neurons are enlisted, leading to a progressively stronger muscle contraction.