Question 1

Which of the following best describes the role of the sarcoplasmic reticulum during skeletal muscle contraction?

Accepted Answer

It stores and releases calcium ions ($$\mathrm{Ca$$^{2+}$$}) $$necessary for muscle contraction.

Question 2

A patient is unable to maintain posture and frequently slumps while sitting. Which function of skeletal muscle is most directly impaired?

Accepted Answer

Posture and body position

Question 3

During a muscle contraction, which of the following changes occur in the sarcomere?

Accepted Answer

The I band and H zone both decrease in width.

Question 4

Which connective tissue layer directly surrounds a bundle of muscle fibers (fascicle)?

Accepted Answer

Perimysium

Question 5

A sprinter relies primarily on which type of muscle fiber during a 100-meter dash?

Accepted Answer

Fast glycolytic fibers

Question 6

Which of the following best describes an isometric muscle contraction?

Accepted Answer

Muscle tension increases but muscle length does not change.

Question 7

Which sequence correctly describes the events at the neuromuscular junction leading to muscle contraction?

Accepted Answer

Nerve impulse arrives → ACh released → Action potential spreads along sarcolemma → Calcium released from SR

Question 8

Which muscle arrangement is characterized by fascicles that converge toward a single tendon, as seen in the pectoralis major?

Accepted Answer

Convergent

Question 9

A person is pushing against a wall with maximum effort, but the wall does not move. Which type of muscle contraction is occurring?

Accepted Answer

Isometric

Question 10

Which of the following is NOT a component of the actin myofilament?

Accepted Answer

Myosin

Question 11

A muscle fiber is unable to relax after repeated stimulation, resulting in a sustained contraction with no relaxation. This condition is known as:

Accepted Answer

Complete tetanus

Question 12

Which of the following best explains why shivering helps maintain body temperature?

Accepted Answer

Muscle contractions during shivering generate heat (thermogenesis).

Question 13

Which of the following best describes the role of a fixator muscle during movement?

Accepted Answer

It stabilizes the origin of the agonist.

Question 14

Which of the following is the correct order of connective tissue layers from innermost to outermost in a skeletal muscle?

Accepted Answer

Endomysium → Perimysium → Epimysium

Question 15

Which of the following best describes the 'triad' in skeletal muscle fibers?

Accepted Answer

One T-tubule and two terminal cisternae of the sarcoplasmic reticulum

Question 16

A marathon runner is most likely to have a high proportion of which muscle fiber type?

Accepted Answer

Slow oxidative fibers

Question 17

Which of the following is a function of axial muscles?

Accepted Answer

Posture, breathing, and movement of the head and trunk

Question 18

Which of the following best describes the role of ATP during muscle contraction?

Accepted Answer

ATP detaches myosin from actin, allowing muscle relaxation.

Question 19

Which of the following is the correct sequence of energy sources used by skeletal muscle during prolonged exercise?

Accepted Answer

Stored ATP → Creatine phosphate → Glycolysis → Aerobic respiration

Question 20

Which of the following best explains why muscle fatigue occurs during intense exercise?

Accepted Answer

Depletion of ATP, ion imbalances, and accumulation of lactic acid

Skeletal Muscle Structure and Function: Study Notes for ANP College Students

Study Guide - Practice Questions