$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{ADP} + \mathrm{P}_i + \text{energy}$$

Question 1

Which of the following best describes the primary source of ATP during the first 10 seconds of a 100-meter sprint?

Accepted Answer

Phosphagen system utilizing creatine phosphate and myokinase

Question 2

A patient with a genetic deficiency in creatine kinase would most likely experience which of the following symptoms during short, intense exercise?

Accepted Answer

Rapid muscle fatigue due to inability to quickly regenerate ATP from creatine phosphate

Question 3

During prolonged moderate exercise (lasting more than 10 minutes), which process supplies the majority of ATP for muscle contraction?

Accepted Answer

Aerobic cellular respiration

Question 4

Which equation correctly represents the breakdown of ATP to release energy for muscle contraction?

Accepted Answer

$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} ightarrow \mathrm{ADP} + \mathrm{P}_i + 	ext{energy}$$

Question 5

Which muscle fiber type is most resistant to fatigue and best suited for maintaining posture?

Accepted Answer

Slow oxidative fibers (Type I)

Question 6

A marathon runner is able to maintain a steady pace for hours. Which adaptation is LEAST likely to be found in their skeletal muscle fibers?

Accepted Answer

Predominance of fast glycolytic fibers

Question 7

Which of the following best explains why muscle fatigue occurs during high-intensity, short-duration exercise?

Accepted Answer

Potassium accumulation in T tubules reducing excitability

Question 8

Which of the following is a function of excess post-exercise oxygen consumption (EPOC)?

Accepted Answer

All of the above

Question 9

Which of the following statements about the phosphagen system is TRUE?

Accepted Answer

It uses creatine phosphate to rapidly regenerate ATP from ADP

Question 10

A weightlifter performing a single, maximal lift is primarily using which energy system?

Accepted Answer

Phosphagen system

Question 11

Which of the following best describes the role of myokinase in muscle metabolism?

Accepted Answer

Transfers a phosphate group from one ADP to another, producing ATP and AMP

Question 12

Which of the following is a characteristic of fast glycolytic (Type IIB) muscle fibers?

Accepted Answer

Fatigue quickly and generate powerful contractions

Question 13

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

Accepted Answer

$$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2 \rightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2\mathrm{O} + 36\ \mathrm{ATP}$$

Question 14

Which of the following would most likely increase the maximum oxygen uptake ($$VO_{2\ max}) of an $$individual?

Accepted Answer

Endurance training that increases mitochondrial density and capillary supply

Question 15

Which of the following is NOT a function of myoglobin in muscle fibers?

Accepted Answer

Directly generating ATP from ADP

Question 16

A sprinter's muscles are primarily using which metabolic pathway during the last 10 seconds of a 30-second all-out sprint?

Accepted Answer

Glycogen-lactate system (anaerobic glycolysis)

Question 17

Which of the following best explains why fast glycolytic fibers appear white in color?

Accepted Answer

They have few mitochondria and low myoglobin content

Question 18

Which of the following adaptations would you expect in the skeletal muscles of a person who regularly performs endurance (aerobic) exercise?

Accepted Answer

Transformation of some fast glycolytic fibers into fast oxidative-glycolytic fibers

Question 19

Which of the following is a correct statement about the control of muscle tension?

Accepted Answer

The total strength of a muscle contraction depends on both the rate of nerve impulses and the number of fibers activated

Question 20

Which of the following best describes the length-tension relationship in skeletal muscle?

Accepted Answer

Maximum tension is generated at an optimal sarcomere length, not when overly stretched or contracted

Muscle Metabolism: ATP Production and Energy Systems in Muscle Fibers

Guida di studio - Domande di pratica