A single contraction of a muscle fiber is called a(n):

Picking up a 45 lb. child would require stimulation of _____ motor units than picking up a 1 lb. brick.

 During the repolarization phase shown on this graph of an action potential along the sarcolemma, ______ ions are flowing rapidly out of the cell and causing the voltage to decrease.

Anabolic steroids mimic testosterone and increase athletic performance by stimulating testicular atrophy.

During the crossbridge cycle, myosin heads enter the cocked position after:

The process that can provided ATP to muscle fibers for longer periods of activity:

 Which of the following best describes this diagram?

A major reason why extra O2 is needed following exercise:

What term refers to the brain increasing the force of a muscle contraction by activating more and more motor units?

Which electrolyte/ion binds with troponin, resulting in the movement of tropomyosin away from the binding sites on actin for myosin heads?