Question 1

Which connective tissue layer directly surrounds each individual skeletal muscle fiber?

Accepted Answer

Endomysium

Question 2

A patient is unable to relax their muscles after death, resulting in rigor mortis. Which of the following best explains this phenomenon?

Accepted Answer

Lack of ATP prevents detachment of myosin heads from actin

Question 3

Which of the following muscle types is characterized by striations, multiple nuclei, and voluntary control?

Accepted Answer

Skeletal muscle

Question 4

During the contraction phase of the crossbridge cycle, what event directly triggers the power stroke?

Accepted Answer

Release of ADP and Pi from the myosin head

Question 5

Which of the following best describes the role of the agonist muscle during movement?

Accepted Answer

It provides the majority of force for the movement

Question 6

A muscle fiber is stimulated repeatedly at a high frequency, resulting in a sustained contraction with no relaxation. What is this phenomenon called?

Accepted Answer

Fused (complete) tetanus

Question 7

Which of the following is the correct sequence of events in excitation-contraction coupling?

Accepted Answer

Action potential in sarcolemma → Release of Ca$$^{2+}$$ from SR → Binding of Ca$$^{2+} to $$troponin

Question 8

Which energy system provides ATP for the first 10 seconds of maximal muscle activity?

Accepted Answer

Immediate cytosolic reactions (creatine phosphate)

Question 9

A baseball player uses different muscle fibers during a game. Which fiber type is primarily used when he swings the bat for a powerful hit?

Accepted Answer

Type IIx and IIb (fast glycolytic)

Question 10

Which of the following best describes the function of acetylcholinesterase (AChE) at the neuromuscular junction?

Accepted Answer

It degrades acetylcholine, ending the signal

Question 11

Which of the following is a property unique to cardiac muscle tissue?

Accepted Answer

Intercalated discs

Question 12

A patient with Duchenne Muscular Dystrophy (DMD) lacks which protein, leading to muscle fiber degeneration?

Accepted Answer

Dystrophin

Question 13

Which of the following best explains why creatine supplementation is only effective for short bursts of muscle activity?

Accepted Answer

Creatine phosphate rapidly regenerates ATP but is quickly depleted

Question 14

Which of the following is true regarding isometric muscle contractions?

Accepted Answer

The muscle length does not change because the external force equals the force generated by the muscle

Question 15

Which of the following is a function of smooth muscle tissue?

Accepted Answer

Peristalsis in hollow organs

Question 16

Which of the following best describes the role of the Z-disc in a sarcomere?

Accepted Answer

It marks the boundary between adjacent sarcomeres

Question 17

A patient is exposed to botulinum toxin. What is the most immediate effect on skeletal muscle function?

Accepted Answer

Paralysis due to blocked acetylcholine release

Question 18

Which of the following best explains why delayed-onset muscle soreness (DOMS) occurs after exercise?

Accepted Answer

Minor structural damage from eccentric contractions

Question 19

Which of the following is a result of endurance training on skeletal muscle fibers?

Accepted Answer

Increase in oxidative enzymes and blood vessel network

Question 20

Which of the following best describes the process of recruitment in muscle contraction?

Accepted Answer

Activating additional motor units to increase force production

Muscle Tissue and Physiology: Structure and Function of the Muscular System

Study Guide - Practice Questions