Exam 6: The Muscular System

Contraction of skeletal muscle is caused by the release of neurotransmitters from ________ neurons.

Which one of the following activities would fast-twitch fibers be most useful for?

Muscles constitute 60-70% of our body mass.

In comparing smooth and cardiac muscle, which one of the following best describes the differences between the two muscle types?

To minimize muscle stiffness and soreness, undertake a new exercise activity in ________ for the first few days.

Muscles of the hand contain a high percentage of fast-twitch fibers, which allows for actions that are strong and quick.

Following running for a long distance, the muscle soreness that occurs the next day is due to chemicals released to repair damaged muscles.

Isometric contractions usually result in no movement of the skeleton or objects.

A protein that stores oxygen in slow-twitch muscle fibers is ________.

According to the ________ principle, a muscle cell contracts completely when adequately stimulated by a motor neuron.

All of the following are necessary for contraction to occur EXCEPT which one?

Which one of the following is found within a sarcomere?

The neurotransmitter, ________, has an excitatory effect on skeletal muscle, causing it to contract.

At the end of the contractile period, energy from the breakdown of ATP is used to

The contractile proteins that are located in myofibrils are called ________ and ________.

The mechanical force that is generated when a muscle contracts is known as ________.

The ability to maintain an upright position is due to ________ muscle contractions.

The following events are associated with muscle contraction. Which one of the following best describes the order in which these events occur, following the initiation of a contraction by a nerve impulse? 1. T tubules transmit electrical impulses throughout the muscle cell. 2) Myosin contacts actin and pulls it toward the center of the sarcomere. 3) Acetylcholine binds to receptors on the muscle. 4) Troponin-tropomyosin complex shifts to expose myosin binding sites. 5) Calcium is released from the sarcoplasmic reticulum.

During a workout session, you may begin to experience a burning sensation in a muscle group that you are targeting with your choice of exercises. This is most likely due to anaerobic metabolism in that muscle, generating ________.