Cardiodynamics

the amount of blood left in the ventricle after it contracts A. cardiac output (CO) B. heart rate (HR) C. end-diastolic volume (EDV) D. stroke volume (SV) E. end-systolic volume (ESV)

End Systolic Volume

The __________ is the amount of blood in a ventricle after it has contracted and before it begins to refill.

End-Systolic Volume

the amount of blood pumped out of the heart during one contraction A. cardiac output (CO) B. heart rate (HR) C. end-diastolic volume (EDV) D. stroke volume (SV) E. end-systolic volume (ESV)

Stroke Volume

The term that describes the volume of blood circulated by the heart in one minute is A) end-systolic volume (ESV). B) end-diastolic volume (EDV). C) stroke volume (SV). D) cardiac output (CO). E) heart rate (HR).

cardiac output (CO)

The volume of blood ejected from each ventricle during a contraction is called the A) cardiac reserve. B) end-diastolic volume. C) cardiac output. D) end-systolic volume. E) stroke volume.

stroke volume

As blood vessel length increases, A) resistance increases. B) flow decreases. C) friction decreases. D) A and B E) A, B, and C

A and B

If the EDV is 140 mL, which other values are most likely to occur in a healthy, normal person? A) The ESV could be 50 mL and the SV could be 90 mL. B) The ESV could be 90 mL and the SV could be 50 mL. C) The ESV could be 70 mL and the SV could be 70 mL. D) A and B E) A and C

A and C

Using the appropriate equations, predict the effects in each scenario.

A. Assuming the same driving pressure, the velocity is the same. Length is not a factor (v = Q/A). B. 256. Q α ΔP/R, so ΔP α R. As R α 1/r4, ΔP α 1/r4. As Q does not change, ΔP1 × r14 = ΔP2 × r24. r14 = 44 = 256. C. increase D. Your water pressure would decline, owing to its diversion to the new subdivision houses.

Michi is on the cross-country team at her college. While she's running, her pulse reaches 150 bpm and her cardiac output reaches 25 liters/min but at rest it's only 65 bpm and 5 liters/min.

A. CO = HR × SV; SV = CO/HR; SV = 254 L/min/150 bpm (exercise) or 5 L/min/65 bpm (rest); SV exercising = 167 mL, rest = 77 mL. Any combination of EDV and ESV where SV = EDV minus ESV. B. Pulse pressure = 40 mm Hg C. Radial pulse = 80 bpm

A person has a total blood volume of 5 L. Of this total, 4 liters is contained in the systemic circulation and 1 L in the pulmonary circulation. If the person has a cardiac output of 5 L/min: A. how long will it take for a drop of blood leaving the left ventricle to return to the heart? B. how long will it take a drop of blood to go from the right ventricle to the left ventricle?

A. SV = 5 L/min, volume = 4 L, which would be distributed in 4/5 min = 48 seconds B. Volume in the pulmonary circuit = 1 L, which would require 1/5 min, or 12 seconds to return to the left atrium from the right ventricle.

You have two tubes: Tube A and Tube B. Tube A has 110 mm Hg at one end and 80 mm Hg at the opposite end. Tube B has 55 mm Hg at one end and 25 mm Hg at the other end.

A. There would be no difference in flow because the pressure difference in Tube A and Tube B is the same (30 mm Hg). B. Water through Tube B because water has a lower viscosity than a milk shake. Resistance is directly proportional to viscosity. Flow is inversely proportional to resistance. Therefore, decreased viscosity = decreased resistance = increased flow. C. No changes because flow is equal in (A.). D. You can change the parameters that would reduce resistance to flow. You could make Tube A shorter or increase its radius. Changing the radius would have a greater impact on increasing flow (Poiseuille's Law).

Miguel is a 25-year-old jogger with a target heart rate of 125 bpm. His resting pulse is 70 bpm. His blood volume is approximately 6.8 liters. At rest, his cardiac output is 6.3 liters/min.

A.90 mL CO = SV * HR; SV=CO/HR = 6.3L/min/ 70 bpm. B. Any combination where EDV minus ESV = 90 mL. Average values are ESV = 44-60 mL, EDV 134-150 mL. C. Yes, the SV changes to 100 mL; EDV probably increases proportionately, to 149-167 mL, thus the ESV would be 49-67 mL. One would assume an increase in venous return would lead to atrial stretching and an increased EDV.

The period of time from the beginning of one heartbeat to the beginning of the next is termed the __________

Cardiac Cycle

the volume of blood circulated by the heart in one minute A. cardiac output (CO) B. heart rate (HR) C. end-diastolic volume (EDV) D. stroke volume (SV) E. end-systolic volume (ESV)

Cardiac Output

The driving force for blood flow is a(n) __________ gradient A) osmotic B) gravity C) volume D) pressure

Pressure

Compare the flow rates (Q) of Tubes one and two, assuming the following parameters. Tube one: ΔP = 30, r = 3, L = 20. Tube two: ΔP = 60, r = 4, L = 10.

Q α ΔP/(L/r4). Q1 α 30/(20/34) = 121. Q2 α 60/(10/44) = 1535. Flow rate in the second tube is about 12 times higher than that in the first tube.

What does the cardiac cycle reveal about the opening and closing of the heart valves? A) There are no times when all four heart valves are closed. B) The AV valves close first, then the semilunars open and close, then the AV valves open. C) There are times when all four heart valves are open. D) The AV valves open, then the semilunars open, then the AV valves close, followed by closure of the semilunars.

The AV valves close first, then the semilunars open and close, then the AV valves open.

Consider the equation F = ΔP/R. It describes the flow (F) of fluid in a tube in which there is a pressure difference (ΔP) between the two ends and a resistance (R) to flow. Based on this equation, which is a correct conclusion? A) If both the resistance and the pressure gradient in a tube increase, the flow must also increase. B) The greater the resistance to flow in a tube, the greater the rate of flow for any given pressure difference. C) The flow of fluid in a tube depends upon the absolute pressure at the beginning of the tube. D) The rate of flow in a tube will decrease if the resistance to flow is decreased. E) The rate of fluid flow in a tube will increase if the pressure at the beginning is increased while the pressure at the end of the tube stays the same.

The rate of fluid flow in a tube will increase if the pressure at the beginning is increased while the pressure at the end of the tube stays the same

The amount of blood returning to the heart is the __________.

Venus Return

If the stroke volume of the left ventricle is 65 mL/beat and the stroke volume of the right ventricle is 68 mL/beat, what will happen to the relative distribution of blood in the systemic and pulmonary circulation after 15 beats?

With each heartbeat, the left side will get "behind" by 3 mLs, with this volume contributing to congestion in the pulmonary circuit; after 15 beats, the deficit will total 45 mL of extra fluid in the pulmonary circuit. This could be the beginning of congestion that sets the stage for congestive heart failure.

The first heart sound heard during the cardiac cycle is associated with ________ A) opening of the AV valves B) closure of the AV valves C) closure of the semilunar valves D) opening of the semilunar valves

closure of the AV valves

Each of the following changes will result in increased blood flow to a tissue except one. Identify the exception A) decreased vessel diameter B) decreased peripheral resistance C) increased blood pressure D) relaxation of precapillary sphincters E) increased blood volume

decreased vessel diameter

Which of the following conditions would have the greatest effect on peripheral resistance? A) doubling the length of a vessel B) doubling the turbulence of the blood C) doubling the number of white cells in the blood D) doubling the diameter of a vessel E) doubling the viscosity of the blood

doubling the diameter of a vessel

The __________ is the amount of blood in a ventricle at the beginning of systole

end-diastolic volume (EDV)

The term used to describe the amount of blood in the ventricle available to be pumped out of the heart during the next contraction is A) end-diastolic volume (EDV). B) heart rate (HR). C) stroke volume (SV). D) cardiac output (CO). E) end-systolic volume (ESV).

end-diastolic volume (EDV)

the amount of blood in the ventricle available to be pumped out of the heart during one contraction A. cardiac output (CO) B. heart rate (HR) C. end-diastolic volume (EDV) D. stroke volume (SV) E. end-systolic volume (ESV)

end-diastolic volume (EDV)

Which of the following changes would most increase the resistance to blood flow in a blood vessel? _______ A) halving the length of the vessel B) doubling the diameter of the vessel C) decreasing the hematocrit from 50% to 40% D) halving the diameter of the vessel E) doubling the length of the vessel

halving the diameter of the vessel

Which parameters are associated with increased resistance? A) increased blood vessel diameter B) reduced flow C) reduced friction D) A and B E) A, B, and C

reduced flow

The cardiac cycle ________. A) is a graph of pressure changes in the heart as it contracts B) is a graph showing the timing of heart valve closure C) represents all of the events of the heart during one heartbeat D) is a graph of electrical activity of the heart

represents all of the events of the heart during one heartbeat

The cardiac output is equal to A) the product of heart rate and stroke volume. B) the stroke volume less the end-systolic volume. C) the product of heart rate and blood pressure. D) the difference between the stroke volume at rest and the stroke volume during exercise. E) the difference between the end-diastolic volume and the end-systolic volume.

the product of heart rate and stroke volume.

Heart sounds are associated with ________. A) turbulent blood flow B) closure of the AV valves C) turbulent blood flow, closure of the AV valves, and closure of the semilunar valves D) closure of the semilunar valves

turbulent blood flow, closure of the AV valves, and closure of the semilunar valves

When a quantity is expressed as "4 cm/sec," what is being described is the A) volume. B) velocity of flow. C) pressure. D) flow rate. E) pressure gradient.

velocity of flow.

According to Starling's law of the heart, the cardiac output is directly related to the A) size of the ventricle. B) thickness of the myocardium. C) heart rate. D) end-systolic volume. E) venous return.

venous return.

The term systole refers to ________. A) ventricular contraction B) atrial depolarization C) atrial contraction D) ventricular depolarization

ventricular contraction

Which phase of the cardiac cycle is longest? A) isovolumetric contraction B) ventricular systole C) ventricular diastole D) isovolumetric relaxation

ventricular diastole

The semilunar valves are forced open when ________. A) atrial contraction occurs B) ventricular pressure exceeds the pressure in the large arteries leaving the heart C) ventricular systole begins D) ventricular diastole begins

ventricular pressure exceeds the pressure in the large arteries leaving the heart

In which situation would the stroke volume be the greatest? A) when the force of contraction is decreased B) when calcium channel blockers are present C) when venous return is decreased D) when venous return is increased E) when the difference between the end-diastolic volume and the end-systolic volume is small

when venous return is increased