Question

question 2
1 part of 1 point
the \motor unit\ in vertebrate skeletal muscle refers to
one sarcomere and all of its actin and myosin filaments.
one myofibril and all of its sarcomeres.
an entire muscle.
one motor neuron and all of the muscle fibers on which it has synapses.
one actin binding site and its myosin partner.

Explanation:

In vertebrate skeletal muscle, a motor unit is defined as one motor neuron and all of the muscle fibers on which it has synapses. When the motor neuron fires, all the associated muscle fibers contract simultaneously.

Answer:

one motor neuron and all of the muscle fibers on which it has synapses.