Chapter 22 : physiology and hemodynamics

Question 1

arteries and veins carry

Answer 1

the same amount of blood

Question 2

____ shape of venous walls offers more resistance than _____ shape

Answer 2

flattened shape offers more flow resistance than circular shape

Question 3

when distended, the cross section of vein is how much larger than the artery

Answer 3

3-4 times as large

Question 4

the extra pulmonary veins carry about ____ of the blood in the body

Answer 4

2/3

Question 5

the shape of the veins are determined by

Answer 5

transmural pressure

pressure within the vein versus pressure outside of the vein

Question 6

low transmural pressure

Answer 6

low volume of blood results in dumbbell shape

Question 7

high transmural pressure

Answer 7

high volume results in circular shape

Question 8

hydrostatic pressure equation

Answer 8

HP = PGH

P= specific gravity of blood
G= acceleration due to gravity
H= distance from the heart

Question 9

HP at ankle supine

Answer 9

presumed to be 0mmHg

Question 10

HP at ankle standing

Answer 10

100 mmHg

Question 11

raised arm HP

Answer 11

-50mmHg

Question 12

what helps propel blood towards the heart

Answer 12

muscle contraction

Question 13

effective calf muscle pump

Answer 13

blood moves from superficial system to deep system
competent valves prevent reflux
venous volume and pressure decreases
venous return to heart increase

Question 14

ineffective calf muscle pump

Answer 14

incompetent valves cause reflux
venous volume and pressure increases
results in venous pooling and ambulatory venous hypertension

Question 15

inspiration

Answer 15

decrease intra-thoracic pressure
increase blood flow from upper extremities
increase intra-abdominal pressure
decrease blood flow from lower extremities

Question 16

exhalation

Answer 16

increase intra-thoracic pressure
decreases blood flow from upper extremities
decrease in intra-abdominal pressure
increases blood flow from lower extremities

Question 17

valsalva maneuver

Answer 17

intra-thoracic and abdominal pressure increase

all venous return halted