A&P2: Cardiovascular - Regulation of Cardiac Output from IP
During exercise, we might expect blood vessels in the skeletal muscle to be somewhat _______________ and the blood vessels in the digestive organs to be somewhat ____________. a. constricted, constricted b. dilated, dilated c. dilated, constricted d. constricted, dilated
c
The flow rate in this activity _______. a. stayed constant, because pump rate increased as the stroke volume increased b. varied with stroke volume c. stayed constant, because pump rate decreased as the stroke volume increased d. stayed constant, because pump rate decreased as the stroke volume decreased
c
When the left flow tube radius was increased, _______. a. the stroke volume increased b. the stroke volume decreased c. the flow rate increased d. the flow rate decreased
c
Which of the following is INCORRECTLY matched with the corresponding equipment used in this experiment? a. left beaker - blood flowing from the heart b. flow tube between the beakers - an artery c. All of the above are matched correctly.
c
An increase in venous return _______. a. occurs during exercise b. results in decreased preload c. decreases EDV d. occurs with severe blood loss
a
Arteries that are closer to the heart _______. a. have more elastic tissue and must be able to withstand pressure changes b. must be able to withstand pressure changes c, have more elastic tissue d. have less elastic tissue e. have less elastic tissue and must be able to withstand pressure changes
a
Describe the plot of pressure versus flow rate. a. It was linear, and the flow rate increased with increased pressure. b. It was curved, and the flow rate increased with increased pressure. c. It was linear, and the flow rate decreased with increased pressure. d. It was curved, and the flow rate decreased with increased pressure.
a
During the ejection period, _______. a. blood is pumped into the aorta and the pulmonary trunk b. the ventricles are filling c. blood is pumped into the pulmonary trunk d. blood is pumped into the aorta e. the atria are filling
a
In the activity, decreasing pressure in the right beaker is analogous to _______. a. decreasing afterload b. decreasing preload c. increasing preload d. increasing contractility
a
In the capillaries, hydrostatic pressure (HP) is exerted by __________. a. blood pressure b. proteins in the blood
a
In the cardiovascular system, the pressure gradient is provided by _______. a. the force of contraction of the heart and peripheral resistance in the blood vessels b. peripheral resistance in the blood vessels c. osmosis d. the force of contraction of the heart
a
Increase in stroke volume is a result of _______. a. increased contractility of the heart, increased EDV and increased preload b. increased EDV c. increased contractility of the heart d. increased preload
a
Increasing the left flow tube radius corresponds to _______. a. increasing preload b. increasing viscosity c. increasing contractility d. increasing afterload
a
The colloid osmotic pressure in the capillary is caused by __________. a. proteins in the blood b. blood pressure
a
The net hydrostatic pressure (HP) is the hydrostatic pressure in the __________ minus hydrostatic pressure in the __________. a. capillary; interstitial fluid b. interstitial fluid; capillary
a
The volume in the pump when the pump piston is all the way down represents the _______. a. end systolic volume b. cardiac output c. stroke volume d. end diastolic volume
a
What variable(s) can the cardiovascular system alter to maintain blood pressure? a. heart rate, stroke volume and resistance b. resistance c. heart rate d. stroke volume
a
When the radius of the flow tube is decreased, the _______. a. fluid flow rate decreases b. friction decreases c. fluid flow rate increases d pressure gradient decreases e. fluid flow rate and the pressure gradient decrease
a
Which net pressure draws fluid into the capillary? a. net osmotic pressure b. net hydrostatic pressure
a
Which of the following has the greatest effect on peripheral resistance? a. blood vessel diameter b. viscosity c. viscosity, blood vessel length and blood vessel diameter affect peripheral resistance equally d. blood vessel length
a
Which of the following would reflect the typical net hydrostatic pressure (HP) at the arterial end of the capillary? a. 34 mm Hg b. 1 mm Hg c. 12 mm Hg
a
Which right flow tube radius resulted in the fastest flow rate? a. 5.0 mm b. All sizes had the same flow rate. c. 3.0 mm d. 1.0 mm
a
Afterload is the pressure threshold that must be exceeded to open _______. a. the tricuspid valve b. the aortic semilunar valve and the pulmonary semilunar valve c. the pulmonary semilunar valve d. the pulmonary semilunar valve and the tricuspid valve e. the aortic semilunar valve
b
An increase in venous return will _______. a. increase stroke volume only b. increase EDV and therefore, increase stroke volume c. increase the contractility of the heart d. increase EDV only
b
An increased preload is equivalent to, or causes, a(n) _______. a. decreased EDV b. increased EDV c. decreased stroke volume d. increased stroke volume
b
Aortic valve stenosis is characterized by _______. a. thickening of the myocardium b. increased resistance to blood flow, thickening of the myocardium and narrowing of the aortic semilunar valve c. narrowing of the aortic semilunar valve d. increased resistance to blood flow
b
How does the body decrease the blood vessel radius? a. vasodilation b. vasoconstriction c. valve closure d. cardiac muscle contraction
b
In this activity, the right flow tube simulates the _______. a. pulmonary trunk b. aorta c. superior vena cava d. pulmonary vein
b
Laminar flow of the blood is achieved through _______. a. vasoconstriction and smooth muscle contraction b. vasodilation c. vasoconstriction d. smooth muscle contraction
b
Reabsorption of fluid into the capillary takes place at the arterial end or venous end of the capillary? a. arterial b. venous
b
The left side of the heart pumps blood _______. a. through the tricuspid valve and to the lungs b. through the aortic valve c. through the tricuspid valve d. to the lungs
b
The overlap length of cardiac muscle in the healthy heart is _______. a. decreased as the heart is stretched b. less than optimum for maximum tension production c. optimum for maximum tension production d. optimized when the length of the sarcomere is decreased
b
Which of the following stayed constant throughout this activity? a. pump rate b. stroke volume c. flow rate d. right flow tube radius
b
Which variable was altered in this activity? a. vessel radius b. stroke volume c. flow rate d. blood pressure
b
Blood flow is _______. a. inversely proportional to cardiac output b. inversely proportional to the pressure gradient c. not proportional to the pressure gradient d. directly proportional to the pressure gradient
d
In this activity, the pump simulates the _______. a. aortic semilunar valve b. right ventricle c. pulmonary semilunar valve d. left ventricle
d
In this activity, we changed the pressure delivered by the left beaker. This is analogous to _______. a. decreasing the radius of the blood vessel b. increasing the viscosity of the blood c. increasing the length of the flow tube d. increasing the force of contraction of the heart
d
In this activity, which variable will be changed? a. vessel radius b. vessel radius and pressure c. vessel length d. pressure
d
Patients with aortic valve stenosis experience _______. a. an increase in chamber volume b. a decrease in chamber volume c. increased thickness in the myocardium and an increase in chamber volume d. increased thickness in the myocardium and a decrease in chamber volume e. increased thickness in the myocardium
d
The compensating mechanisms tested in this activity include all of the following EXCEPT _______. a. increasing preload b. increasing contractility c. decreasing afterload d. decreasing preload
d
The flow rate of a liquid is _______. a. directly proportional to the resistance b. directly proportional to the pressure gradient and the resistance c. inversely proportional to the pressure gradient d. directly proportional to the pressure gradient
d
The free-flowing blood located in the middle of a blood vessel is called _______. a. friction flow b. lumen flow c. gradient flow d. laminar flow
d
When the flow tube radius increased, _______. a. resistance decreased b. pump rate increased to maintain pressure c. pump rate decreased to maintain pressure d. resistance decreased and pump rate increased to maintain pressure e. resistance decreased and pump rate decreased to maintain pressure
d
Which of the following result(s) in an increase in fluid flow rate? a. increase in radius diameter b. increase in pressure c. decrease in radius diameter d. increase in pressure and increase in radius diameter e. increase in pressure and decrease in radius diameter
d
How would a decrease in blood volume affect both stroke volume and cardiac output?
decreased stroke volume and no change in cardiac output Yes, a decreased blood volume would decrease the end diastolic volume, thus lowering the stroke volume. Although this would initially lead to a decrease in the cardiac output, heart rate would increase because of increased activity of the sympathetic nervous system in an effort to maintain cardiac output.
Cardiac output is _______. a. equal to heart rate times stroke volume b. equal to blood flow c. equal to heart rate times (EDV minus ESV) d. equal to blood flow and equal to heart rate times stroke volume e. All of the above.
e
Which of the following would increase heart rate?
epinephrine and norepinephrine Yes, secreted by the adrenal medulla as a result of sympathetic stimulation, these hormones act as part of the sympathetic response, increasing heart rate.
How would an increase in the sympathetic nervous system increase stroke volume?
increased contractility Yes, an increase in sympathetic nervous system activity would increase contractility (by increasing available calcium), thus increasing stroke volume. Contractility causes an increase in stroke volume by decreasing end systolic volume; it does not change end diastolic volume.
By what mechanism would an increase in venous return increase stroke volume?
increased end diastolic volume Yes, an increase in venous return increases the end diastolic volume. The fibers are stretched more, resulting in an increase in the force of contraction (preload, or the Frank-Starling Mechanism).
Which of the following would increase cardiac output to the greatest extent?
increased heart rate and increased stroke volume Yes, cardiac output = heart rate x stroke volume.
