Question 1

Which property of muscle allows it to be passively stretched without damage?

Accepted Answer

Extensibility

Question 2

A muscle fascicle is surrounded by which connective tissue layer?

Accepted Answer

Perimysium

Question 3

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

Accepted Answer

Stores and releases calcium ions ($$\mathrm{Ca$$^{2+}$$}) $$for muscle contraction

Question 4

Which protein anchors myofibrils to the sarcolemma, helping maintain muscle structure?

Accepted Answer

Dystrophin

Question 5

During the power stroke of muscle contraction, which event occurs?

Accepted Answer

Myosin heads bind to actin and pull the thin filament toward the center of the sarcomere

Question 6

If a drug interferes with the active transport of $$\mathrm{Ca$$^{2+}$$}$$ back into the sarcoplasmic reticulum, what is the likely effect?

Accepted Answer

Muscle will remain contracted due to sustained high $$\mathrm{Ca$$^{2+}$$}$$ levels

Question 7

What would happen if acetylcholinesterase is absent from the synaptic cleft at the neuromuscular junction?

Accepted Answer

Acetylcholine would accumulate, causing prolonged muscle contraction

Question 8

Where is sodium ($$\mathrm{Na^+}) $$most concentrated when a muscle fiber is at rest?

Accepted Answer

Outside the muscle fiber

Question 9

Which event occurs during depolarization of a muscle fiber's action potential?

Accepted Answer

Sodium ($$\mathrm{Na^+}) $$ions enter the cell

Question 10

What is the primary role of myoglobin in muscle tissue?

Accepted Answer

Stores oxygen for aerobic metabolism

Question 11

Which organelle is essential for aerobic respiration in muscle fibers?

Accepted Answer

Mitochondrion

Question 12

A marathon runner's muscles are rich in which type of muscle fiber?

Accepted Answer

Slow oxidative fibers

Question 13

What is the effect of curare, a poison that blocks acetylcholine receptors at the motor end plate?

Accepted Answer

Muscle contraction is inhibited, leading to paralysis

Question 14

Which type of muscle contraction occurs when the muscle length does not change, such as holding a weight steady?

Accepted Answer

Isometric contraction

Question 15

Which branch of the nervous system controls smooth muscle contraction?

Accepted Answer

Autonomic nervous system

Question 16

What is the name for a condition where stimuli occur so rapidly that there are no intervening relaxations between contractions?

Accepted Answer

Complete tetanus

Question 17

Which muscle tissue type is striated, branched, and joined by intercalated discs?

Accepted Answer

Cardiac muscle

Question 18

What is a by-product of anaerobic respiration in muscle fibers?

Accepted Answer

Lactic acid

Question 19

Which of the following best describes the difference between visceral and multi-unit smooth muscle?

Accepted Answer

Visceral smooth muscle contracts as a unit (e.g., intestines), while multi-unit contracts independently (e.g., iris)

Question 20

A patient with prolonged immobilization (e.g., wearing a cast) is likely to experience which effect on their muscles?

Accepted Answer

Muscle atrophy

Muscular System Study Guide – Step-by-Step Guidance

Study Guide - Practice Questions