C- Hemodynamics & Vasculature

Question 1

________ is Highest in aorta.

Answer 1

Pressure

Pressure decreases through system, especially in resistance vessels (sm arteries & arterioles)

Question 2

Pressure is_______ in capillaries and venous system

Answer 2

low

Question 3

Total blood volume ~ 5 L

Largest volume in _______(“capacitance vessels”)

Answer 3

veins

Question 4

Q = DP/R

this represents?

Answer 4

Q = DP/R

Pressure differences (ΔP) drive blood flow (Q). Vascular resistance (R) opposes blood flow.

Question 5

volume per unit time (ml/min)
CONSTANT through system (since closed loop)
CARDIAC OUTPUT (CO) = Total flow in the cardiovascular system

Answer 5

Flow (Q)

Question 6

distance per unit time (cm/sec)
v=Q/A (flow/cross sectional area)
Velocity highest in aorta (lowest total cross-sectional area), lowest in capillaries (greatest cross-sectional area).

Answer 6

Velocity (v)

Question 7

CO = (Pa-Pv)/TPR

Answer 7

Cardiac Output

Pa = mean arterial blood pressure
Pv = venous blood pressure
TPR = total peripheral resistance

Variation of flow equation: Q=DP/R

Question 8

_______ is the volume of blood pumped per minute by the heart (~5 L/min at rest)

Answer 8

Cardiac Output (CO)
CO = (Pa-Pv)/TPR

Question 9

___________ corresponds to the total flow in cardiovascular system

Answer 9

Cardiac Output

CO = (Pa-Pv)/TPR

Question 10

Flow is proportional to 4th power of radius. Thus ___________ is the biggest determinant of flow.

Answer 10

radius of vessel

Question 11

Flow is proportional to ____________. Thus radius of vessel is the biggest determinant of flow.

Answer 11

4th power of radius

Question 12

resistance of a parallel network is ________ than the resistance of any single vessel

Answer 12

lower

*Changing the resistance of a single vessel has little effect on the system

Question 13

Total resistance of a series of vessels is _________ than the resistance of any individual vessel

Answer 13

higher

*Resistances in series are additive

Question 14

(flow)
Most efficient
Velocity fastest in center, zero at edge
Flow equation assumes this flow. Not true in CV system

Answer 14

Laminar flow

Question 15

(flow)

Irregular, with eddies and vortices

Less efficient – requires more pressure to achieve same velocity

Promoted by large diameter, high velocity, low viscosity, changes in diameter, and irregularities on walls

Answer 15

Turbulent flow

*Turbulent flow produces shearing forces that can damage vascular endothelium

Question 16

Heartbeat produces _____ flow in aorta, but _____ flow requires more work. dampened in arterial system.

Answer 16

pulsatile

Question 17

FLOW IS __________IN CAPILLARIES

Answer 17

CONTINUOUS

Question 18

Systolic pressure =

Answer 18

peak aortic pressure

Question 19

Diastolic pressure =

Answer 19

minimum aortic pressure

Question 20

Blood pressure is expressed as

Answer 20

systolic/diastolic = ex 120/80 mmHg

Question 21

Vessels lose compliance with age =

Answer 21

arteriosclerosis

Compliance represents the elastic properties of vessels (or chambers)

Question 22

arteriosclerosis results in

Answer 22

Older people have higher systolic pressure and higher pulse pressure than younger people

Question 23

Tension in wall increases as pressure and radius increase.

Walls of larger vessels subject to greater tension.

________ increases stress on walls of vessels and chambers.

Answer 23

Hypertension

Question 24

Law of LaPlace:

Answer 24

Relationship between wall tension & transmural pressure

Question 25

Cardiovascular Transport Two processes

Answer 25

Bulk transport

Transcapillary transport

Question 26

refers to movement of a substance through the cardiovascular system from point A to point B.

Answer 26

Bulk transport

Question 27

describes the movement of a substance between capillaries and tissue

Answer 27

Transcapillary transport

Question 28

Diffusion follows _________ concentration gradients

Answer 28

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