QUESTIONS WITH CORRECT VERIFIED ANSWERS-
A+ GRADED , SUCCESS GUARANTEED
1. To which of the following structures do the cross-bridges attach during muscle action?
a. actin
b. myosin
c. M-bridge
d. sarcolemma - ANSWER actin
2. Which of the following substances regulates muscle actions?
a. potassium
b. calcium
c. troponin
d. tropomyosin - ANSWER calcium
3. Which of the following substances acts at the neuromuscular junction to excite the muscle
fibers of a motor unit?
a. acetylcholine
b. ATP
c. creatine phosphate
d. serotonin - ANSWER acetylchooline
,4. Which of the following muscle fiber types is the MOST beneficial for a marathon runner?
a. Type I
b. Type IIa
c. Type IIx
d. Type IIc - ANSWER Type I
5. When throwing a baseball, an athlete's arm is rapidly stretched just prior to throwing the ball.
Which of the following structures detects and responds to that stretch by reflexively increasing
muscle activity?
a. Golgi tendon organ
b. muscle spindle
c. extrafusal muscle
d. Pacinian corpuscle - ANSWER Muscle spindle
6. From which of the following is the heart's electrical impulse normally initiated?
a. AV node
b. SA node
c. the brain
d. the sympathetic nervous system - ANSWER SA node
7. Which of the following occurs during the QRS complex of a typical ECG?
I. depolarization of the atrium
II. repolarization of the atrium
III. repolarization of the ventricle
,IV. depolarization of the ventricle
a. I and III only
b. II and IV only
c. I, II, and III only
d. II, III, and IV only - ANSWER Repolarization of the atrium; depolarization of the ventricle (II
and IV only)
1. Which of the following is the ultimate source of energy for a muscular contraction?
a. GTP
b. oxygen
c. NADH
d. ATP - ANSWER ATP
2. Which of the following substances can be metabolized anaerobically?
a. protein
b. carbohydrate
c. fat
d. glycerol - ANSWER carbohydrate
3. The predominant energy system used during a training session depends primarily on the
a. session intensity.
b. session duration.
, c. athlete's training status.
d. athlete's lean body mass. - ANSWER Session intensity
4. The production of lactic acid results from the activation of which of the following energy
systems?
a. phosphagen
b. slow glycolysis
c. fast glycolysis
d. fat oxidation - ANSWER Fast glycolysis
5. Which of the following energy systems has the highest rate of energy production?
a. phosphagen
b. fast glycolysis
c. fat oxidation
d. carbohydrate oxidation - ANSWER phosphagen
6. Approximately how many ATP are produced via the oxidative energy system from the
degradation of one glucose molecule?
a. 27
b. 36
c. 38
d. 41 - ANSWER 38
7. Which of the following energy systems is predominantly active at the initiation of all exercise?