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 contraction.

Question 2

A patient is unable to relax their muscles after a contraction. Which malfunction is most likely responsible?

Accepted Answer

Failure of the sarcoplasmic reticulum to reabsorb $$\mathrm{Ca$$^{2+}$$}$$ ions.

Question 3

During a biceps curl, which muscle acts as the antagonist?

Accepted Answer

Triceps brachii

Question 4

Which connective tissue layer directly surrounds individual muscle fibers?

Accepted Answer

Endomysium

Question 5

Which of the following changes occur in the sarcomere during muscle contraction?

Accepted Answer

The I band decreases in width.

Question 6

A marathon runner's leg muscles are primarily composed of which type of muscle fiber?

Accepted Answer

Slow oxidative fibers

Question 7

Which of the following best describes an isometric muscle contraction?

Accepted Answer

Muscle tension increases but muscle length does not change.

Question 8

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

Accepted Answer

Action potential arrives, ACh released, calcium binds troponin, tropomyosin moves, myosin binds actin.

Question 9

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

Accepted Answer

Convergent

Question 10

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

Accepted Answer

Isometric

Question 11

Which of the following is NOT a function of skeletal muscle?

Accepted Answer

Storing calcium ions

Question 12

Which component of the thin filament blocks the active sites on actin in a resting muscle?

Accepted Answer

Tropomyosin

Question 13

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 14

Which energy source is primarily used by skeletal muscle at rest?

Accepted Answer

Aerobic respiration of fatty acids and glucose

Question 15

Which of the following is a correct pairing of muscle and its arrangement?

Accepted Answer

Rectus femoris – bipennate

Question 16

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

Accepted Answer

Temporary loss of ability to contract due to ATP depletion and lactic acid accumulation

Question 17

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 18

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

Accepted Answer

It stabilizes the origin of the agonist.

Question 19

Which of the following muscle fiber types would be most prevalent in the quadriceps of a sprinter?

Accepted Answer

Fast glycolytic fibers

Question 20

Which of the following is a function of axial muscles?

Accepted Answer

Posture and movement of the head and trunk

Skeletal Muscle Structure and Function: ANP Study Guide

Study Guide - Practice Questions