Q: Which equation correctly represents the direct phosphorylation of ADP by creatine phosphate?

$$\mathrm{CP} + \mathrm{ADP} \xrightarrow{\text{creatine kinase}} \mathrm{Creatine} + \mathrm{ATP}$$

Question 1

Which of the following best describes the role of ATP in muscle contraction?

Accepted Answer

ATP is required to move and detach cross bridges, pump calcium back into the sarcoplasmic reticulum, and restore ion gradients after excitation-contraction coupling.

Question 2

A sprinter is running a 100-meter dash that lasts about 10 seconds. Which energy pathway is primarily supplying ATP during this activity?

Accepted Answer

Direct phosphorylation of ADP by creatine phosphate

Question 3

Which equation correctly represents the direct phosphorylation of ADP by creatine phosphate?

Accepted Answer

$$\mathrm{CP} + \mathrm{ADP} \xrightarrow{	ext{creatine kinase}} \mathrm{Creatine} + \mathrm{ATP}$$

Question 4

Which muscle fiber type is best suited for maintaining posture over long periods?

Accepted Answer

Slow oxidative fibers

Question 5

During prolonged, moderate-intensity exercise (e.g., marathon running), which substrate becomes the main fuel source for ATP production after about 30 minutes?

Accepted Answer

Fatty acids

Question 6

Which of the following is a correct sequence of events in the anaerobic pathway for ATP synthesis in muscle?

Accepted Answer

Glycogen → Glucose → Glycolysis → Pyruvic acid → Lactic acid

Question 7

A patient with a genetic mutation that reduces myosin ATPase activity would most likely have which of the following symptoms?

Accepted Answer

Slower muscle contraction speed

Question 8

Which of the following best explains why fast glycolytic fibers fatigue more quickly than slow oxidative fibers?

Accepted Answer

They rely primarily on anaerobic glycolysis, which produces less ATP per glucose and leads to lactic acid accumulation.

Question 9

Which of the following equations represents the net ATP yield from aerobic respiration of one glucose molecule?

Accepted Answer

$$\mathrm{Glucose} + 6\mathrm{O}_2 \rightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2\mathrm{O} + 32\ \mathrm{ATP}$$

Question 10

Which of the following statements about motor units is correct?

Accepted Answer

A motor unit consists of a motor neuron and all the muscle fibers it innervates.

Question 11

Which muscle fiber type would be most prevalent in the quadriceps of a competitive sprinter?

Accepted Answer

Fast glycolytic fibers

Question 12

Which process is responsible for converting lactic acid produced in muscles back into glucose in the liver?

Accepted Answer

The Cori cycle

Question 13

A person is performing a high-intensity activity lasting 45 seconds. Which energy pathway is primarily supplying ATP during this time?

Accepted Answer

Anaerobic glycolysis

Question 14

Which of the following best explains why all muscle fibers in a single motor unit are the same type?

Accepted Answer

They are innervated by the same motor neuron, which determines their fiber type.

Question 15

Which of the following is a characteristic of fast oxidative fibers?

Accepted Answer

High myoglobin content, intermediate fatigue resistance, and suited for sprinting or walking.

Question 16

Which of the following best describes the recruitment order of muscle fiber types during increasing intensity of exercise?

Accepted Answer

Slow oxidative fibers are recruited first, followed by fast oxidative, then fast glycolytic.

Question 17

Which of the following is NOT a function of ATP in muscle contraction?

Accepted Answer

Storing oxygen for aerobic respiration

Question 18

Which of the following best explains why genetics play a role in athletic performance related to muscle fiber types?

Accepted Answer

Genetics determine the percentage of each muscle fiber type in an individual.

Question 19

Which of the following is a correct statement about the duration of energy provided by each ATP regeneration pathway?

Accepted Answer

Direct phosphorylation provides energy for about 15 seconds.

Question 20

Which of the following best describes the main difference between oxidative and glycolytic muscle fibers?

Accepted Answer

Oxidative fibers use aerobic pathways for ATP synthesis, while glycolytic fibers use anaerobic glycolysis.

Muscle Contraction and Metabolism: Study Notes for ANP College Students

Study Guide - Practice Questions

Study Guide - Flashcards