Question 1

Which property of muscle cells allows them to respond to a stimulus, such as a nerve impulse, and generate an action potential?

Accepted Answer

Excitability

Question 2

During muscle contraction, which protein forms the thin filament within the sarcomere?

Accepted Answer

Actin

Question 3

A patient presents with muscle weakness due to an autoimmune attack on acetylcholine receptors at the neuromuscular junction. What is the most likely diagnosis?

Accepted Answer

Myasthenia gravis

Question 4

Which structure surrounds individual muscle fibers (myocytes) within a fascicle?

Accepted Answer

Endomysium

Question 5

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

Accepted Answer

Store and release calcium ions

Question 6

Which type of muscle fiber is best adapted for endurance activities such as marathon running?

Accepted Answer

Slow twitch (red fibers)

Question 7

In the sliding filament model of contraction, which event directly follows the binding of acetylcholine to its receptor on the sarcolemma?

Accepted Answer

Generation of an action potential in the muscle cell membrane

Question 8

Which enzyme is responsible for breaking down acetylcholine in the synaptic cleft, terminating muscle stimulation?

Accepted Answer

Esterase

Question 9

A muscle contraction in which the muscle length does not change, but tension increases, is called:

Accepted Answer

Isometric contraction

Question 10

Which of the following best describes the role of creatine phosphate in muscle contraction?

Accepted Answer

It rapidly donates a phosphate group to ADP to regenerate ATP.

Question 11

If a muscle is stretched beyond its optimum length before contraction, what is the expected effect on the force generated?

Accepted Answer

Force decreases because fewer cross-bridges can form.

Question 12

Which of the following is a waste product of anaerobic fermentation in muscle cells?

Accepted Answer

Lactic acid

Question 13

During the cross-bridge cycle, what directly causes the myosin head to detach from actin?

Accepted Answer

Binding of ATP to the myosin head

Question 14

Which muscle tissue type is characterized by striations and voluntary control?

Accepted Answer

Skeletal muscle

Question 15

A person with muscle atrophy is most likely experiencing which of the following?

Accepted Answer

Decrease in muscle fiber size

Question 16

Which of the following best explains why slow twitch (red) muscle fibers are more resistant to fatigue?

Accepted Answer

They have abundant mitochondria and myoglobin.

Question 17

Which part of a skeletal muscle is the point of attachment that remains relatively stationary during contraction?

Accepted Answer

Origin

Question 18

Which regulatory protein blocks the myosin binding sites on actin in a resting muscle?

Accepted Answer

Tropomyosin

Question 19

If a person is unable to coordinate voluntary muscle movements due to a neurological disorder, which condition is most likely present?

Accepted Answer

Ataxia

Question 20

Which equation best represents the ATP yield from aerobic respiration of one molecule of glucose in muscle cells?

Accepted Answer

$\approx 36 	ext{ ATP}$

Muscle Tissue: Structure, Function, and Physiology

Study Guide - Practice Questions

Study Guide - Flashcards