Cardiovascular functions Flashcards
During dynamic exercise, the predominate stimulus initiating cardiovascular responses is increased activity from the muscle metaboreceptors.
True or False?
False
In addition to the effect that sympathetic stimulation has on the myocardium, it also affects blood flow throughout the body by which of the following vasomotor actions?
A. vasodilution
B. vasodilation
C. vasoconstriction
D. none of the above
Vasoconstriction
What is preload as it relates to the cardiac cycle?
A. Preload is the amount of blood that is ejected from the heart during systole.
B. Preload is the resistance to ejection that the heart faces during systole.
C. Preload is the amount of blood in the left ventricle after the filling phase of the cardiac cycle.
D. None of the above
Preload is the amount of blood in the left ventricle after the filling phase of the cardiac cycle.
During low to moderate-intensity exercise, heart rate is increased by?
A.inhibition of parasympathetic stimulation.
B. activation of sympathetic stimulation
C. both A and B
D. neither A or B
inhibition of parasympathetic stimulation
Mean arterial pressure during exercise:
A. Lies half-way between the systolic and diastolic pressures and can be computed as the mathematical mean of these two measures.
B. Can be estimated as one-third pulse pressure plus diastolic blood pressure.
C. Generally increases with exercise.
D. A and C
E. B and C
B and C
The cardiovascular control center is responsible for regulating which major functions of the cardiovascular system?
A. hearts output of blood
B. preferential distribution of blood to the tissues
C. elimination of carbon dioxide from the blood
D. both A and B
Hearts output of Blood and preferential distribution of blood to the tissues.
At rest, increased arterial blood pressure is compensated for by:
Decreased heart rate.
Decreased stroke volume.
Decreased total systemic peripheral resistance.
All of the above.
None of the above.
All of the above.
Which of the following is an example of a peripheral receptor that sends feedback to the cardiovascular center?
chemoreceptor
baroreceptor
mechanoreceptor
all of the above
all of the above
Which of the following can provoke NO (nitric oxide) synthesis and release from the vascular endothelium?
A. sheering stress
B. vessel stretch from blood flow
C. stimuli from neurotransmitters
D. all of the above
all of the above
During maximum exercise by healthy men and women, systolic blood pressure may increase to _____ mm Hg.
> 200 mm Hg
During bouts of aerobic exercise, what changes happen to heart rate and myocardial contractility?
increase
Which of the following variables is most noted to have a downward displacement when the situation of cardiovascular drift is present?
stroke volume
The most important factors in regulating blood flow in the intact human include:
Pressure gradient and vessel radius.
At rest, what is the normal value of oxygen carried in one litre of arterial blood?
200mL
Cardiac output during exercise regarding T and UT athletes.
Is higher in a well-trained athlete vs. untrained subjects at maximal work levels.
Endurance athletes achieve higher cardiac outputs through large increases in which variable of the cardiac output formula?
stroke volume
Resting stroke volume for untrained and trained persons are about the same.
True or Flase?
False
The inherent rhythmicity or beating of the heart is approximately how many beats per minute?
100 beats
What is central commands function?
Controls parasympathetic tone to the heart.
When one begins to exercise what happens to the value of a-vO2 difference from rest towards maximal exercise?
increases
Which of the following statements would be true for sub-maximal exercise that is achieved through arm ergometry?
Arm exercise has higher oxygen consumption demands than leg exercise at sub-maximal levels.
During low to moderate-intensity exercise, heart rate is increased by?
inhibition of parasympathetic stimulation.
The Fick equation expresses the relationship between cardiac output, _______, and a-vO2 difference
VO2
During exercise __________ activity to the myocardium __________ causing an __________ in heart rate.
Sympathetic, increases, increase.
A trained athlete has a lower resting cardiac output than does an untrained person.
False
Nitric Oxide causes what changes in blood vessels?
vasodilation and decreased vascular resistance
During whole body strenuous dynamic exercise the arterial baroreceptor reflex:
Is reset to a higher operating point.
During bouts of exercise, there is a shunting of blood towards active tissues. However, certain areas cannot compromise their blood supply. Which of the following areas would not be able to compromise its supply?
heart and brain
A decrease in stroke volume (supply) during increased aerobic work can lead to the development of what condition of the myocardium?
myocardial ischemia
