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Which of the following substances regulates muscle actions?
potassium
calcium
troponin
tropomyosin - ANSWER calcium
Which of the following substances acts at the NMJ to excite the muscle fibers of a motor
unit?
acetylcholine
ATP
creatine phosphate
serotonin - ANSWER acetylcholine
When throwing a baseball, an athlete's arm is rapidly stretched just before throwing the ball.
Which of the following structures detects and responds to that stretch by reflexively
increasing muscle activity?
golgi tendon organ
muscle spindle
extrafusal muscle
pacinian corpuscle - ANSWER muscle spindle
1
,From which of the following is the heart's electrical impulse normally initiated?
AV node
SA node
the brain
the sympathetic nervous system - ANSWER SA node
Which of the following occurs during the QRS complex of a typical ECG?
1. depolarization of the atrium
2. repolarization of the atrium
3. repolarization of the ventricle
4. depolarization of the ventricle
a. 1 and 3 only
b. 2 and 4 only
c. 1, 2, and 3 only
d. 2, 3, and 4 only - ANSWER b. 2 and 4 only
Which of the following is the definition of power?
mass x acceleration
force x distance
force x velocity
torque x time - ANSWER force x velocity
To compare performances of Olympic weightlifters of different body weights, the classic
formula divides the load lifted by the athlete's
2
,body weight
body weight squared
lean body weight
body weight to the two-thirds power - ANSWER body weight to the two-thirds
power
During a free weight exercise, muscle force varies with which of the following?
1. perpendicular distance from the weight to the body joint
2. joint angle
3. movement acceleration
4. movement velocity squared
a. 1 and 2 only
b. 1 and 4 only
c. 1, 2, and 3 only
d. 2, 3, and 4 only - ANSWER a. 1 and 2 only (perpendicular distance from the
weight to the body joint AND joint angle)
A vertical jump involves knee, hip, and shoulder movement primarily in which of the
following anatomical planes?
sagittal
perpendicular
frontal
transverse - ANSWER sagittal
3
, An athlete is performing a concentric isokinetic elbow flexion and extension exercise. Which
of the following type(s) of lever occur(s) at the elbow during this exercise?
1. 1st class
2. 2nd class
3. 3rd class
a. 1 only
b. 2 only
c. 1 and 3 only
d. 2 and 3 only - ANSWER c. 1 and 3 only
Which of the following substances can be metabolized anaerobically?
glycerol
glucose
amino acids
free fatty acids - ANSWER glucose
Which of the following reactions is the primary cause of metabolic acidosis (decrease in
intramuscular pH during high-intensity, fatiguing exercise)?
ATP = ADP + Pi + H+
pyruvate + NADH = lactate + NAD+
ADP + creatine phosphate = ATP + creatine
fructose-6-phosphate = fructose-1,6-biphosphate - ANSWER ATP = ADP + Pi + H+
Which of the following energy systems produces ATP at the quickest rate?
4
Which of the following substances regulates muscle actions?
potassium
calcium
troponin
tropomyosin - ANSWER calcium
Which of the following substances acts at the NMJ to excite the muscle fibers of a motor
unit?
acetylcholine
ATP
creatine phosphate
serotonin - ANSWER acetylcholine
When throwing a baseball, an athlete's arm is rapidly stretched just before throwing the ball.
Which of the following structures detects and responds to that stretch by reflexively
increasing muscle activity?
golgi tendon organ
muscle spindle
extrafusal muscle
pacinian corpuscle - ANSWER muscle spindle
1
,From which of the following is the heart's electrical impulse normally initiated?
AV node
SA node
the brain
the sympathetic nervous system - ANSWER SA node
Which of the following occurs during the QRS complex of a typical ECG?
1. depolarization of the atrium
2. repolarization of the atrium
3. repolarization of the ventricle
4. depolarization of the ventricle
a. 1 and 3 only
b. 2 and 4 only
c. 1, 2, and 3 only
d. 2, 3, and 4 only - ANSWER b. 2 and 4 only
Which of the following is the definition of power?
mass x acceleration
force x distance
force x velocity
torque x time - ANSWER force x velocity
To compare performances of Olympic weightlifters of different body weights, the classic
formula divides the load lifted by the athlete's
2
,body weight
body weight squared
lean body weight
body weight to the two-thirds power - ANSWER body weight to the two-thirds
power
During a free weight exercise, muscle force varies with which of the following?
1. perpendicular distance from the weight to the body joint
2. joint angle
3. movement acceleration
4. movement velocity squared
a. 1 and 2 only
b. 1 and 4 only
c. 1, 2, and 3 only
d. 2, 3, and 4 only - ANSWER a. 1 and 2 only (perpendicular distance from the
weight to the body joint AND joint angle)
A vertical jump involves knee, hip, and shoulder movement primarily in which of the
following anatomical planes?
sagittal
perpendicular
frontal
transverse - ANSWER sagittal
3
, An athlete is performing a concentric isokinetic elbow flexion and extension exercise. Which
of the following type(s) of lever occur(s) at the elbow during this exercise?
1. 1st class
2. 2nd class
3. 3rd class
a. 1 only
b. 2 only
c. 1 and 3 only
d. 2 and 3 only - ANSWER c. 1 and 3 only
Which of the following substances can be metabolized anaerobically?
glycerol
glucose
amino acids
free fatty acids - ANSWER glucose
Which of the following reactions is the primary cause of metabolic acidosis (decrease in
intramuscular pH during high-intensity, fatiguing exercise)?
ATP = ADP + Pi + H+
pyruvate + NADH = lactate + NAD+
ADP + creatine phosphate = ATP + creatine
fructose-6-phosphate = fructose-1,6-biphosphate - ANSWER ATP = ADP + Pi + H+
Which of the following energy systems produces ATP at the quickest rate?
4
