Chapter 3 - Muscle And Exercise Metabolism

Question 0

Transports oxygen

Answer 0

Myoglobin

Question 1

Cytokine that stimulates glycogen breakdown

Answer 1

Interleukin-6

Question 2

Aerobic metabolism that occurs in the mitochondrion

Answer 2

TCA cycle

Question 3

Contractile unit of a muscle fiber

Answer 3

Sarcomere

Question 4

Metabolism of fat stores

Answer 4

Lypolysis

Question 5

Thin myofilament

Answer 5

Actin

Question 6

Transports action potential to sarcoplasmic reticulum

Answer 6

T-tubules

Question 7

Enzyme that breaks down ATP for energy

Answer 7

ATPase

Question 8

Protein filament that blocks binding sites on actin

Answer 8

Tropomyosin

Question 9

Thick Filament

Answer 9

Myosin

Question 10

_________ muscle fibers have fast contractile speed capability with an oxidative capacity that makes them moderately resistant to fatigue.

Answer 10

Type 2a

Question 11

Muscle fibers are recruited by size and speed in the following order: _____, then ________, and finally _______ when needed

Answer 11

I, IIa, IIx

Question 12

List the three primary sources of energy metabolism (modes of ATP re synthesis) in the order they occur based on activity duration

Answer 12

A. PCr hydrolysis
B. Glycolysis
C. Oxidative phosphorylation

Question 13

True or False? PCr provides energy that is sufficient to fuel short duration, high-intensify exercise such as interval sprints.

Answer 13

True

Question 14

True or false? Hydrogen ions released during glycolysis lower the pH level in muscle, increasing enzyme activity.

Answer 14

False

Question 15

List four sources of energy storage in the human body

Answer 15

A) fat
B) Protein
C) Blood glucose
D) Muscle glycogen

Question 16

Fat stores provide fuel at a rate that can maintain exercise intensity up to ______ VO2max

Answer 16

60%

Question 17

Fill in the missing components of the following table addressing hormones that regulate energy metabolism.

Hormone: Insulin

Source: Pancreas

Stimuli for Activation: _________________

Actions: ______________________

Answer 17

Stimuli for Activation: increase in glucose and amino acids

Actions: glucose/a.a uptake
Inhibits lipolysis + protein breakdown

Question 18

Hormone: Epinephrine

Source:_________________

Stimuli for activation: stress and drop in blood glucose

Actions: _________________

Answer 18

Source: stress, fall in glucose

Actions: glycogen breakdown, lipolysis in adipose tissue

Question 19

Hormone:________________

Source: Adrenal cortex

Stimuli for Activation:________________

Actions: stimulates protein breakdown and lipolysis

Answer 19

Hormone: cortisol

Stimuli for Activation: stress, hormonal activators

Question 20

Hormone: Growth Hormone

Source:__________________

Stimuli for Activation: Stress

Actions:__________________

Answer 20

Source: anterior pituitary gland

Actions: liver glycogen breakdown, lipolysis in adipose tissue, cortisol secretion

Question 21

True or false? Glycogen depletion is the limiting factor for fatigue during prolonged, sub maximal exercise

Answer 21

True

Question 22

List two muscular adaptations to aerobic training that improve endurance capacity.

Answer 22

A. Increase capillary density

B. Increase mitochondrial size and quantity

Question 23

Which of the following structures function to store calcium for use during muscular contractions?

A. Sarcomere
B. Myosin
C. Sarcoplasmic Reticulum
D. Myoglobin

Answer 23

C

Question 24

Type I muscle fibers do NOT present with which of the following characteristics? A. Slow contraction rate B. High capacity for oxidative metabolism C. Capacity to perform repeated contractions for a long period of time D. Low capillary density

Answer 24

D

Question 25

Which of the following fiber types would be found in the highest proportion in a postural muscle such as the soleus? A. Type I fibers B. Type IIa fibers C. Type IIx fibers D. Type III fibers

Answer 25

A

Question 26

Which of the following selections is the ultimate source of energy for all muscular work? A. PCr B. ATP C. Glycogen D. Fatty acids

Answer 26

B

Question 27

Which of the following systems of metabolism involve the breakdown of carbohydrate without the presence of oxygen to fuel high-intensity, shorter duration exercise? A. B-oxidation B. PCr hydrolysis C. Glycolysis D. Lipolysis

Answer 27

C

Question 28

Normal resting glycogen stores are usually depleted after which of the following durations of continuous intense exercise? A. 30-45 min. B. 1-2 hours C. 3.5-5.0 hours D. Glycogen stores are rarely depleted

Answer 28

B

Question 29

Energy levels within muscle are regulated by each of the following except? A. Enzymatic reactions B. Sympathetic nervous system activity C. Hormonal activity D. Lactate synthesis

Answer 29

D

Question 30

Which of the following hormones stimulate liver glycogen breakdown and glyconeogenesis in response to a drop in blood glucose levels? A. Insulin B. Interleukin-6 C. Glucagon D. Growth hormone

Answer 30

C

Question 31

Which of the following is the primary cause of fatigue during high-intensity exercise lasting 1-5 minutes? A. PCr depletion B. Fat depletion C. Hydrogen ion accumulation D. Acetyl-coA accumulation

Answer 31

C

Question 32

Which of the following is not a muscular adaptation to aerobic training? A. Increased mitochondrial size and quantity B. Increased cross-sectional area of type I muscle fibers C. Increased capacity to use fat as an energy source during sub maximal efforts D. Increased short-term glycolytic energy-delivery systems.

Answer 32

D