Ch. 17

Question 1

What is the average Cardiac Output in the human body?

Answer 1

5L/min

NOTE: Can increase 5-fold during exercise

Question 2

What is the average heart rate?

Answer 2

60-100 BPM

Question 3

How does the heart perfuse?

Answer 3

The heart perfuses directly via coronary arteries

Question 4

Describe the valves in the ventricle. Which valves are where?

Answer 4

Left Inlet: Mitral Valve
Left Outlet: Aortic Valve
Right Inlet: Tricuspid Valve
Right Outlet: Pulmonary Valve

Question 5

Explain the pathway of blood through the heart.

Answer 5

Lungs –> Pulmonary Vein –> Left Atrium –> Mitral Valve –> Left Ventricle –> Aortic Valve –> Aorta –> Body –> Vena Cava –> Right Atrium –> Tricuspid Valve –> Right Ventricle –> Pulmonary Valve –> Pulonary Artery –> Lungs

Question 6

Write the equations for CO (also with Fick Principle), resistance, Reynold’s Number, Ejection Fraction, Stroke Volume, Pulse Pressure, MAP, compliance, Blood Flow.

Answer 6

How’d you do?

Question 7

Draw and label the PV loop? Describe the segments.

Answer 7

How’d you do?

Question 8

Using Poisseuille’s Law, describe the relationship between resistance and a) viscosity b) length and c) fourth power of the radius

Answer 8

A) Directly related to viscosity
B) Directly related to length
C) Inversely related to the fourth power of the radius
NOTE: *Flow will have the opposite relationship with these properties.

Question 9

What effect does adding more resistors in series have on the total resistance? Parallel?

Answer 9

Series: Increase R_total
Parallel: Decrease R_total

Question 10

Describe laminar flow.

Answer 10

1. Silent
2. Fluid moves slowly and the layers do not mix
3. Promoted by laminar flow

Question 11

Describe Turbulent Flow

Answer 11

1. Noisy
2. Fluid layers mix
3. Causes loss of energy
4. Common at valves, branching, and areas of plaque buildup

Question 12

At what value of Reynold’s Number is flow laminar? Turbulent?

Answer 12

Laminar: Re < 2000
Turbulent: Re > 3000

Question 13

Driving Pressure

Answer 13

Difference in pressure along the axis of the vessel - governs blood flow

Question 14

Transmural Pressure

Answer 14

Pressure across the vessel wall - governs vessel diameter

Question 15

Hydrostatic Pressure

Answer 15

Pressure imposed by gravity

Question 16

Pulse Pressure

Answer 16

Systolic Pressure - Diastolic Pressure

Question 17

MAP (Mean Arterial Pressure)

Answer 17

Average BP

Question 18

Compliance

Answer 18

measures how distensible a vessel is for a given change in pressure

Question 19

Which is more compliant: Veins or arteries?

Answer 19

Veins

Question 20

Describe the Bernoulli Effect

Answer 20

Blood flows from an area of higher to lower total energy

As fluid flows along the tube with a narrow central region, pressure is actually lower in the narrow region than the ends of the tube