$$ \text{Creatine Phosphate} + \text{ADP} \rightarrow \text{Creatine} + \text{ATP} $$

$$ \text{Glucose} + 2 \text{ADP} + 2 \text{P}_i \rightarrow 2 \text{Lactic Acid} + 2 \text{ATP} $$

Question 1

Which of the following statements best describes the difference between skeletal and smooth muscle tissue?

Accepted Answer

Skeletal muscle is striated and under voluntary control, while smooth muscle is non-striated and under involuntary control.

Question 2

A patient is experiencing muscle fatigue after intense exercise. Which of the following is the most likely cause of this fatigue?

Accepted Answer

Accumulation of lactic acid, ATP deficit, and ionic imbalance within the muscle cells.

Question 3

During muscle contraction, which event occurs at the neuromuscular junction?

Accepted Answer

Acetylcholine is released into the synaptic cleft and binds to receptors on the motor end plate.

Question 4

Which of the following best explains the sliding filament model of muscle contraction?

Accepted Answer

Thin filaments slide past thick filaments, increasing overlap and shortening the sarcomere.

Question 5

Which formula correctly represents the regeneration of ATP by creatine phosphate during skeletal muscle contraction?

Accepted Answer

$$ 	ext{Creatine Phosphate} + 	ext{ADP} ightarrow 	ext{Creatine} + 	ext{ATP} $$

Question 6

A muscle is immobilized in a cast for several weeks. What physiological change is most likely to occur?

Accepted Answer

Muscle cells will decrease in size due to lack of stimulation, a process known as atrophy.

Question 7

Which of the following is a function unique to smooth muscle compared to skeletal muscle?

Accepted Answer

Ability to contract rhythmically as a unit via gap junctions.

Question 8

Which of the following best describes the role of calcium ions in skeletal muscle contraction?

Accepted Answer

Calcium ions bind to troponin, causing a conformational change that exposes myosin binding sites on actin.

Question 9

Which of the following equations represents the process of anaerobic glycolysis in muscle cells?

Accepted Answer

$$ 	ext{Glucose} + 2 	ext{ADP} + 2 	ext{P}_i ightarrow 2 	ext{Lactic Acid} + 2 	ext{ATP} $$

Question 10

A muscle twitch consists of three phases. Which sequence correctly describes these phases?

Accepted Answer

Latent period, contraction phase, relaxation phase.

Question 11

Which of the following best explains why aerobic exercise increases endurance but not muscle hypertrophy?

Accepted Answer

Aerobic exercise increases capillary penetration, mitochondria, and myoglobin synthesis, improving metabolism without increasing cell size.

Question 12

Which of the following is true regarding the force of muscle contraction?

Accepted Answer

Force increases as the number of muscle fibers stimulated increases.

Question 13

A weightlifter is performing an isometric exercise. Which statement best describes what is happening in the muscle?

Accepted Answer

The muscle length remains constant while tension increases.

Question 14

Which of the following is a characteristic of fast glycolytic muscle fibers?

Accepted Answer

Low resistance to fatigue and rapid contraction speed.

Question 15

Which of the following best describes the effect of increasing load on the velocity and duration of muscle contraction?

Accepted Answer

As load increases, velocity decreases and duration shortens.

Question 16

Which of the following is a unique feature of smooth muscle contraction compared to skeletal muscle?

Accepted Answer

Smooth muscle contraction involves calcium binding to calmodulin, activating myosin light chain kinase.

Question 17

Which of the following best describes the phenomenon of muscle tone?

Accepted Answer

Muscles exhibit slight contraction even when at rest, keeping them firm and ready to respond.

Question 18

Which of the following is true regarding the regulation of smooth muscle contraction?

Accepted Answer

Both acetylcholine and norepinephrine can be released, causing excitation or inhibition depending on the muscle group.

Question 19

A person is exposed to a cold environment and begins shivering. Which process is responsible for the heat production during shivering?

Accepted Answer

Muscle contraction increases metabolic activity, generating heat as a byproduct.

Chapter 9: Muscles – Structure, Function, and Physiology

Study Guide - Practice Questions