Question 1

Which energy system provides the fastest source of ATP for muscle contraction during maximal effort lasting less than 20 seconds?

Accepted Answer

Creatine phosphate (CP) system

Question 2

During intense exercise when oxygen is limited, what is the fate of pyruvic acid produced from glycolysis?

Accepted Answer

It is converted to lactic acid

Question 3

Which equation correctly represents the reaction catalyzed by creatine kinase in the phosphagen system?

Accepted Answer

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

Question 4

After exercise, how is lactic acid processed in the body when oxygen becomes available?

Accepted Answer

It is oxidized back to pyruvate, which can enter the citric acid cycle

Question 5

Which muscle fiber type is most resistant to fatigue and is best suited for endurance activities?

Accepted Answer

Type I (slow oxidative)

Question 6

Which process is responsible for generating glucose from non-carbohydrate sources during prolonged fasting?

Accepted Answer

Gluconeogenesis

Question 7

What is the total ATP yield from the complete aerobic oxidation of one molecule of glucose?

Accepted Answer

$\sim 32$ ATP

Question 8

Which of the following is a major cause of muscle fatigue during intense exercise?

Accepted Answer

Ion imbalance (K$^+$, Na$^+$, Ca$^{2+}$)

Question 9

Which pathway is primarily used for ATP production during a 5k-10k run?

Accepted Answer

Aerobic glycolysis

Question 10

What is the role of Acetyl CoA in cellular energy production?

Accepted Answer

It enters the citric acid cycle for ATP generation

Question 11

Which of the following best describes the Cori cycle?

Accepted Answer

Conversion of lactic acid to pyruvic acid in the liver, then to glucose

Question 12

Which muscle fiber type would be most prevalent in elite sprinters?

Accepted Answer

Type IIb (fast glycolytic)

Question 13

During recovery from exercise, which process helps restore ATP and CP levels in muscle?

Accepted Answer

Aerobic metabolism using extra oxygen (EPOC)

Question 14

Which of the following is NOT a product of aerobic metabolism of glucose?

Accepted Answer

Lactic acid

Question 15

Which equation best represents the overall reaction for aerobic metabolism of glucose?

Accepted Answer

$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2 \rightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2\mathrm{O} + \sim 32\ \mathrm{ATP}$

Question 16

Which of the following is a common source of glucose for ATP synthesis during intense exercise?

Accepted Answer

Glycogen stored in the liver and muscle

Question 17

Which muscle fiber type is characterized by high myoglobin content, many mitochondria, and slow contraction speed?

Accepted Answer

Type I (slow oxidative)

Question 18

Which process is most important for maintaining blood glucose levels during prolonged periods without food?

Accepted Answer

Gluconeogenesis in the liver

Question 19

Which of the following statements about anaerobic glycolysis is TRUE?

Accepted Answer

It is used when oxygen supply is limited during intense activity

Question 20

A marathon runner is most likely to rely on which energy system after 30 minutes of continuous running?

Accepted Answer

Aerobic lipolysis

Muscle Metabolism and Fiber Types: Study Guide for Anatomy & Physiology

Study Guide - Practice Questions