Question 1

Which of the following is a property shared by all three types of muscle tissue (skeletal, cardiac, and smooth)?

Accepted Answer

They all exhibit electrical excitability and can generate action potentials.

Question 2

A patient with Duchenne muscular dystrophy is likely to experience progressive muscle weakness because of a defect in which protein?

Accepted Answer

Dystrophin

Question 3

During the contraction cycle, what is the role of ATP hydrolysis at the myosin head?

Accepted Answer

It reorients the myosin head to a perpendicular 'cocked' position, ready to bind actin.

Question 4

Which connective tissue layer surrounds individual muscle fibers?

Accepted Answer

Endomysium

Question 5

What is the primary function of the sarcoplasmic reticulum in skeletal muscle fibers?

Accepted Answer

To store and release calcium ions for muscle contraction

Question 6

Which band of the sarcomere contains only thick filaments and no thin filaments?

Accepted Answer

H band

Question 7

A marathon runner relies primarily on which type of skeletal muscle fiber for endurance activities?

Accepted Answer

Slow-twitch oxidative fibers (Type 1)

Question 8

Which of the following best describes the sliding filament mechanism of muscle contraction?

Accepted Answer

Myosin heads pull thin filaments toward the M line, increasing overlap; filament length remains unchanged.

Question 9

Which regulatory protein blocks the myosin-binding site on actin when the muscle is relaxed?

Accepted Answer

Tropomyosin

Question 10

What is the main function of sphincters composed of smooth muscle?

Accepted Answer

To prevent outflow of contents in organs by contracting and closing passageways

Question 11

Which of the following equations correctly represents the hydrolysis of ATP during muscle contraction?

Accepted Answer

$$ATP \rightarrow ADP + P$$

Question 12

A patient is unable to maintain muscle contraction after prolonged activity. Which of the following is NOT a likely cause of muscle fatigue?

Accepted Answer

Excessive oxygen supply to muscle fibers

Question 13

Which structural protein connects the Z disc to the M line and provides elasticity and extensibility to the sarcomere?

Accepted Answer

Titin (Connectin)

Question 14

Which of the following is TRUE regarding cardiac muscle tissue?

Accepted Answer

It is striated, has one nucleus per cell, and is under involuntary control.

Question 15

Which of the following best explains why the resting sarcomere length is optimal for maximum tension generation?

Accepted Answer

There is considerable overlap between thick and thin filaments, allowing maximum cross-bridge formation.

Question 16

Which connective tissue component provides a pathway for nerves, blood vessels, and lymphatic vessels to enter and exit muscles?

Accepted Answer

Subcutaneous tissue

Question 17

Which of the following statements about the neuromuscular junction (NMJ) is correct?

Accepted Answer

It is the synapse between a somatic motor neuron and a skeletal muscle fiber.

Question 18

Which of the following is a function of myoglobin in skeletal muscle fibers?

Accepted Answer

Binds to oxygen and releases it to mitochondria for ATP production

Question 19

Which of the following is TRUE about the arrangement of filaments in smooth muscle tissue?

Accepted Answer

Thick and thin filaments are not arranged in sarcomeres, resulting in a non-striated appearance.

Question 20

Which of the following best describes the role of the perimysium?

Accepted Answer

It surrounds bundles of muscle fibers, forming muscle fascicles.

Muscle Tissue: Structure, Function, and Physiology (Chapter 10 Study Notes)

Study Guide - Practice Questions