Theme 26 - Cardio 3

Question 1

What is blood velocity determined by?

Answer 1

total cross sectional area

Question 1

what is cardiac output?

Answer 1

heart rate and stroke volume, volume of blood pumped by the heart per minute

Question 1

what is arterial pressure and Ohm’s law?

Answer 1

pressure flow and resistance

Question 1

What is Poiseuille’s law do do with the arterioles?

Answer 1

radius and flow resistance

Question 1

What is an example of a compound with is an endothelial derived relaxing factor?

Answer 1

Nitric oxide

Question 1

how is pulse pressure found?

Answer 1

systolic minus diastolic

Question 1

how does the aorta dampen pressure and flow pulses?

Answer 1

storing volume in diastole

Question 1

what is the velocity of blood flow infersely related to?

Answer 1

total cross sectional area

Question 1

how is cardiac output increased?

Answer 1

increasing heart rate or stroke volume

Question 1

if a person has a resting heart rate of 70 bpm and a resting stroke volume of 70 mL/beat, what is their resting cariac output?

Answer 1

70 x 70 = 4900 mL/min

Question 1

how is mean arterial pressure determined?

Answer 1

cardiac output x total peripheral resistance (ohm’s law)

Question 1

What is total peripheral resistance?

Answer 1

vascular resistance to flow of blood in systemic circulation (arterioles provide greatest resistance)
- resistance and pressure are proportional to eachother, when arterioles vasoconstrict, TPR increases = increase of MAP

Question 1

What is the most important factor controlling total peripheral resistance?

Answer 1

radius of arterioles

Question 1

what are the 4 factors of aortic pressure?

Answer 1

systolic
diastolic
pulse
mean pressure

Question 1

how is pulse pressure reduced?

Answer 1

by the elastic properties of the aorta

Question 1

where is flow velocity the lowest?

Answer 1

capillaries

Question 1

what are the resistance vessels called that cause the largest pressure drop?

Answer 1

arterioles

Question 1

what three things does Ohm’s law relate?

Answer 1

cardiac output(blood flow)
resistance
mean arterial pressure

Question 1

how can the arteriole radius be changed?

Answer 1

by smooth muscle activity

Question 1

what is NO (nitrogen oxide) produced by?

Answer 1

the endothelium

Question 1

what does the NO gas produced by the endothelium do?

Answer 1

dilates vessels
reduces resistance
reduces mean arterial pressure