Quiz #4

Question 1

The Motor neuron and all the muscle fibers it innervates is called a

Answer 1

motor unit

Question 2

The two prinicipal contractile protein filaments found in skeletal muscle are

Answer 2

actin and myosin

Question 3

TRUE OR FALSE: At any given velocity of movement, the peak force is greater in muscles that contain a high percentage of fast twitch fibers when compared to muscles that possess predominantly slow twitch fibers

Answer 3

True

Question 4

Fast-Twitch fibers contain a relatively

Answer 4

small number of mitochondria and high ATPase activity

Question 5

The trigger to initiate the contractile process in skeletal muscles is

Answer 5

calcium binding to troponin

Question 6

During the initial period of disuse (i.e., 2 days), muscle atrophy is predominantly due to

Answer 6

decreased protein synthesis

Question 7

The site where the motor neuron and muscle cell meet is called the

Answer 7

motor unit

Question 8

TRUE OR FALSE: In sprinting type activities, ONLY fast twitch muscle fibers are recruited

Answer 8

True

Question 9

Calcium is stored in muscle within the

Answer 9

sarcoplasmic reticulum

Question 10

Type IIx fibers __________.

Answer 10

have high specific tension

Question 11

Which of the following ECGs indicates myocardial ischemia?

Answer 11

ST Segment depression

Question 12

All the gas exchange between the vascular system and tissues occur in

Answer 12

Capillaries

Question 13

The back flow of blood from left ventricle to the left atrium is prevented by the

Answer 13

Bicuspid Valve

Question 14

Diastolic Pressure provides an indication of:

Answer 14

Peripheral Resistance

Question 15

The pacemaker potential of the heart is initiated by

Answer 15

inherent leakage of Na+

Question 16

The earliest gains in strength training is primarily due to _________

Answer 16

All of the above

Question 17

As exercise intensity increases

Answer 17

Viscera blood flow decreases

Question 18

The ______ represents ventricular contraction during a recording of ECG of the heart

Answer 18

QRS complex

Question 19

The volume of gas that reaches the respiratory zone (gas-exchange zone) of the lung is termed

Answer 19

Alveolar ventilation

Question 20

Which is the predominant factor in Fick’s law of gas diffusion?

Answer 20

Partial pressure between the two sides of the tissue

Question 21

During incremental exercise, ventilation increases as a linear function of oxygen uptake up to a point known as _________ where the ventilation increases exponentially.

Answer 21

Ventilatory threshold

Question 22

During exercise, the increase in ventilation would _______.

Answer 22

All of the above

Question 23

Baroreceptors are located in ______________.

Answer 23

Carotid Sinus

Question 24

Which of the following factors does NOT cause an increase in stroke volume during strenuous exercise?

Answer 24

increase in heart rate

Question 25

TRUE/FALSE During exercise an increase in alveolar ventilation serves to lower arterial PCO2 and maintain normal blood pH.

Answer 25

True

Question 26

TRUE/FALSE The right shift of the oxygen-hemoglobin dissociation curve indicates the decrease in oxygen affinity to hemoglobin.

Answer 26

True

Question 27

TRUE/FALSE At rest, inhalation is caused by diaphragm relaxation

Answer 27

FALSE

Question 28

Which of the following is a characteristic of myocardium?

Answer 28

All of the above

Question 29

In order to meet the increased oxygen demands of the active skeletal muscles during exercise, what adjustments in blood flow should be made?

Answer 29

Increase in cardiac output and a redistribution of blood flow from inactive tissue to the active skeletal muscles.

Question 30

The most important variable that determines resistance to blood flow is _____

Answer 30

The radius of the vessel

Question 31

Which of the following ejection fractions of the heart indicates depression of myocardial contraction?

Question 32

The function of the baroreflex is to _______________.

Answer 32

Normalize blood pressure

Question 33

Which of the following formulas can be used to calculate ejection fraction?

Answer 33

Ejection Fraction = SV/EDV

Question 34

Which of the following factors would cause a decrease in EDV during high-intensity exercise?

Answer 34

Increased Heart Rate

Question 35

Which of the following factors causes an increase in blood flow the most in the active skeletal muscles during exercise?

Answer 35

Increase in Sympathetic Nervous Activity

Question 36

During a prolonged exercise (2 hours) in a hot weather and no water intake available, the hematocrit of the athlete would be ________.

Answer 36

Increased

Question 37

Exercise at the intensity of ____________ VO2 max induces the greatest stroke volume.

Answer 37

40-60%

Question 38

The fact that an increase in EDV increases the stroke volume of the heart is an illustration of ______.

Answer 38

the decrease in total peripheral resistance

Question 39

Which of the following is NOT a right cardiovascular response of a healthy individual to a dynamic exercise?

Answer 39

increase in diastolic blood pressure

Question 40

Compared with a leg exercise at the same workload, arm exercise tends to induce _________.

Answer 40

Higher HR (Not sure if this is correct)

Question 41

TRUE/FALSE During heavy exercise, the heart may spend more time in systole than in diastole/

Answer 41

TRUE

Question 42

During exercise the cardiovascular center I the brain stem that receives feedback from _______ and then adjusts the cardiovascular system to meet the need to exercise.

Answer 42

All of the above

Question 43

The relationship between oxygen uptake, cardiac output, and the arterial-venous oxygen difference is described mathematically by the

Answer 43

Fick’s Equation

Question 44

The most resistance to blood flow is in the _________.

Answer 44

Arterioles

Question 45

Which of the following is true of the heart rate change during exercise?

Answer 45

the increase in HR is due to PNS withdrawal followed by increasing SNS influence

Question 46

TRUE/FALSE Trained endurance runners have lower ventilatory threshold than untrained individuals because trained runners have adapted to the exercise

Answer 46

False

Question 47

Person A has a VO2max value of 4 L/min. Person B has a VO2max value of 3 L/min. Based on the information above, which of the following statements is correct?

Answer 47

Their fitness levels cannot be compared based on the given information.

Question 48

The hemoglobin level for a healthy man is about ________ g/dl.

Answer 48

15

Question 49

Which of the following factors is NOT the right response to acute exercise?

Answer 49

Vasodilation in viscera

Question 50

Oxygenated blood returns to the heart via the _____.

Answer 50

Pulmonary vein

Question 51

The majority of CO2 in our body is transported by

Answer 51

Bicarbonate

Question 52

TRUE/FALSE The increase in parasympathetic activity would significantly decrease the heart rate.

Answer 52

True

Question 53

TRUE/FALSE Pulmonary artery contains deoxygenated blood

Answer 53

TRUE

Question 54

TRUE/FALSE Hemoglobin can only carry oxygen

Answer 54

FALSE

Question 55

Which of the following is the right blood flow pathway (starting with deoxygenated blood)?

Answer 55

Vena Cava -> Right Atrium -> Right Ventricle -> Lungs -> Left Atrium -> Left Ventricle -> Aorta

Question 56

_______________ is defined as the maximum amount of gas that can be expired after a maximum inspiration.

Answer 56

Vital Capacity

Question 57

Cardiovascular drift is characterized as ______________________.

Answer 57

Increase in heart rate and a decrease in stroke volume.

Question 58

Which one of the following most likely causes cardiovascular drift?

Answer 58

Long duration exercise in a hot/humid weather

Question 59

When exercise (prolonged exercise) at steady state in hot/humid environment ventilation tends to _____________.

Answer 59

Increase