Exam 9: Skeletal Muscle: Structure and Function

Fast-twitch fibers contain a relatively

The motor neuron and all the muscle fibers it innervates are called a motor

Calcium is stored in muscle within the

Which of the following has been shown to cause muscle fatigue?

Recent evidence suggests that rigorous exercise training can result in a conversion of muscle fiber type.

The site where the motor neuron and muscle cell meet is called the

The two principal contractile proteins found in skeletal muscle are

In contrast to power athletes, endurance athletes typically possess a low percentage of slow fibers and a high percentage of fast fibers.

The formation of cross-bridges in the contractile process in skeletal muscle is

The amount of force exerted during muscular contraction is dependent on the

Which of the following events in muscle contraction is the first to occur chronologically?

Type IIx fibers

High activity of the enzyme ATPase is found in both slow-twitch and fast-twitch fibers.

Rigor mortis is caused by an inability of myosin to enter a weak binding state with actin.

The change in muscle fiber type that would most likely occur as a result of endurance training is

Tetanus is defined as the use of sufficient motor units to initiate movements.

Muscle atrophy may be caused by a decrease in protein production, as well as an increase in protein degradation.

If you continue to increase the firing rate (of action potentials) of a motor neuron, then all of the skeletal muscle fibers it innervates will eventually summate to tetanus.

Which of the following events in muscle contraction is the last to occur chronologically?

A successful endurance athlete would likely have ________________ compared to a sedentary person.