$\mathrm{ATP} \rightarrow \mathrm{ADP} + \mathrm{Pi} + \text{energy}$

Creatine phosphate $\rightarrow$ glycolysis $\rightarrow$ aerobic respiration

Question 1

Which of the following best describes a motor unit in skeletal muscle physiology?

Accepted Answer

A single neuron and all the muscle fibers it innervates

Question 2

During a sustained muscle contraction, which process is primarily responsible for the initial rapid production of ATP?

Accepted Answer

Creatine phosphate donating a phosphate to ADP

Question 3

Which of the following factors does NOT directly influence the force generated by a skeletal muscle contraction?

Accepted Answer

Amount of oxygen in the blood

Question 4

A marathon runner’s muscles are able to sustain activity for long periods. Which muscle fiber type is most abundant in their leg muscles?

Accepted Answer

Slow oxidative fibers

Question 5

Which equation correctly represents the breakdown of ATP during muscle contraction?

Accepted Answer

$\mathrm{ATP} ightarrow \mathrm{ADP} + \mathrm{Pi} + 	ext{energy}$

Question 6

Which of the following best explains muscle fatigue during intense exercise?

Accepted Answer

Accumulation of lactic acid and depletion of ATP

Question 7

Isotonic and isometric contractions differ in which of the following ways?

Accepted Answer

Isotonic contractions change muscle length, isometric contractions do not

Question 8

Which adaptation is most likely to occur in skeletal muscle after months of resistance exercise?

Accepted Answer

Hypertrophy due to increased myofibril size

Question 9

A patient is unable to maintain muscle tone in their limbs. Which of the following is most likely impaired?

Accepted Answer

Continuous low-level stimulation of motor units

Question 10

Which of the following is a correct multi-step pathway for ATP production during prolonged exercise?

Accepted Answer

Creatine phosphate $\rightarrow$ glycolysis $\rightarrow$ aerobic respiration

Question 11

Which of the following best describes the response of skeletal muscle to endurance exercise?

Accepted Answer

Increase in capillary density and mitochondrial number

Question 12

Which variable does NOT affect the velocity of skeletal muscle contraction?

Accepted Answer

Amount of connective tissue in the muscle

Question 13

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

Accepted Answer

Contraction is regulated by calmodulin instead of troponin

Question 14

A sprinter’s muscles fatigue quickly during a race. Which muscle fiber type is most responsible for this?

Accepted Answer

Fast glycolytic fibers

Question 15

Which of the following equations represents the regeneration of ATP from ADP using creatine phosphate?

Accepted Answer

$\mathrm{ADP} + \mathrm{CP} \rightarrow \mathrm{ATP} + \mathrm{C}$

Question 16

Which scenario best illustrates the concept of muscle tone?

Accepted Answer

A person’s muscles remain slightly contracted even when at rest

Question 17

Which of the following is a common misconception about muscle fatigue?

Accepted Answer

It is caused solely by the depletion of oxygen

Question 18

Which of the following best describes the effect of increasing the frequency of stimulation on muscle contraction?

Accepted Answer

It leads to summation and potentially tetanus

Question 19

Which process is most important for ATP production during long-duration, low-intensity exercise?

Accepted Answer

Aerobic respiration

Question 20

Which of the following is NOT a way that the force of a muscle contraction can be varied?

Accepted Answer

Altering the number of mitochondria in the muscle

Muscle Contraction and Metabolism: Study Notes for Anatomy & Physiology

Study Guide - Practice Questions