Question 1

Which of the following statements best describes the difference between skeletal, cardiac, and smooth muscle tissue?

Accepted Answer

Skeletal muscle is voluntary and striated, cardiac muscle is involuntary and striated, smooth muscle is involuntary and non-striated.

Question 2

A patient is experiencing muscle fatigue after prolonged exercise. Which of the following is LEAST likely to contribute to muscle fatigue?

Accepted Answer

Increase in ATP supply

Question 3

Which connective tissue layer directly surrounds a single skeletal muscle fiber?

Accepted Answer

Endomysium

Question 4

During the sliding filament theory of muscle contraction, which event occurs FIRST after calcium ions are released from the sarcoplasmic reticulum?

Accepted Answer

Regulatory proteins on actin are exposed

Question 5

Which of the following is TRUE regarding the energy pathways for muscle contraction?

Accepted Answer

Direct phosphorylation by creatine phosphate is the fastest way to regenerate ATP.

Question 6

A muscle cell returns to its resting state after contraction by:

Accepted Answer

Diffusion of potassium ions out of the cell and activation of the sodium-potassium pump

Question 7

Which of the following best explains why skeletal muscle is considered voluntary?

Accepted Answer

It is the only muscle tissue subject to conscious control.

Question 8

Which structure stores and releases calcium ions necessary for muscle contraction?

Accepted Answer

Sarcoplasmic reticulum

Question 9

A muscle contraction in which tension increases but the muscle does NOT shorten is called:

Accepted Answer

Isometric contraction

Question 10

Which of the following is the correct sequence of events at the neuromuscular junction leading to muscle contraction?

Accepted Answer

Release of acetylcholine, opening of sodium channels, depolarization, action potential, breakdown of acetylcholine

Question 11

If a muscle is stimulated so rapidly that no evidence of relaxation is seen and contractions are smooth and sustained, this is called:

Accepted Answer

Fused (complete) tetanus

Question 12

Which formula correctly represents the direct phosphorylation of ADP by creatine phosphate?

Accepted Answer

$$\mathrm{CP} + \mathrm{ADP} \rightarrow \mathrm{Creatine} + \mathrm{ATP}$$

Question 13

Which of the following is a function unique to skeletal muscle compared to other muscle types?

Accepted Answer

Maintaining posture and body position

Question 14

Which property allows muscle cells to return to their resting length after being stretched?

Accepted Answer

Elasticity

Question 15

A marathon runner relies primarily on which pathway for ATP regeneration during the race?

Accepted Answer

Aerobic respiration

Question 16

Which of the following best describes the 'all-or-none' law of muscle fiber contraction?

Accepted Answer

A muscle fiber contracts to its fullest extent when stimulated adequately.

Question 17

Which of the following is TRUE about the structure of a sarcomere?

Accepted Answer

The Z disc anchors actin filaments.

Question 18

Which of the following is a result of aerobic (endurance) exercise?

Accepted Answer

Muscles become more flexible and resistant to fatigue

Question 19

Which of the following is the correct formula for ATP production during aerobic respiration?

Accepted Answer

$$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2 \rightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2\mathrm{O} + 32\mathrm{ATP}$$

Question 20

Which of the following is TRUE about muscle tone?

Accepted Answer

It is a state of continuous partial contractions keeping muscles firm and ready for action.

Study Notes: The Muscular System (Anatomy & Physiology)

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