Cardio 3

Question 1

Where is pressure the highest

Answer 1

Aorta

Question 2

Pulse pressure

Answer 2

Systolic pressure - diastolic pressure

Question 3

mean arterial pressure

Answer 3

• driving pressure for blood flow
  = diastolic pressure + 1/3 (pulse pressure)

direct proportional to CO x resistance

Question 4

Sympathetic reflexes/control of vascular smooth muscle (resistance is influenced by these) (changes the radius of vessels)

Answer 4

Main determinant of resistance in arterioles is sympathetic nervous system

• increase in norepinephrine binds to alpha one adrenergic receptors and causes constriction
• epinephrine binds to beta 2 adrenergic receptors and causes dilation

Question 5

sphygmomanometer

Answer 5

• cuff inflates and stops arterial blood flow (no sound heard)
• Korotkoff sounds are created by pulsatile blood flow through compressed artery. Sounds=change in BF; velocity increase = turbulent
• blood flow is silent when artery isnt compressed

Question 6

factors that influence mean arterial BP

Answer 6

1. relative distribution of blood between arterial and venous blood vessels
   - determined by vein diameter
2. blood volume
   - fluid intake and fluid loss
3. CO
4. Resistance

Question 7

where is resitance the highest

Answer 7

• arterioles because they are in series

- greater than 60% of resistance in arteriole flow

Question 8

Local control

Answer 8

• matches tissue blood flow to the metabolic needs of tissue

Question 9

myogenic auto regulation

Answer 9

contracts arteriole in response to stretching of vascular smooth muscle. This prevents too much blood from entering capillaries

Question 10

paracrines alter vascular smooth muscle

Answer 10

decrease oxy, CO2, NO, H+, causes dialation, decrease resistance and increase blood low, O2 and nutrient supply to tissue increases

Question 11

medullary cardiovascular control center (CVCC)

Answer 11

integrating center; controls distribution and pressure of blood

Question 12

baroreceptor reflex

Answer 12

maintains mean arterial blood pressure

- incr BP the baroreceptors sense the strech and increase firing rate and BP is decreased

Question 13

peripheral chemoreceptors

Answer 13

sense alterations in blood-gas [] , O2 and CO2 and pH

Question 14

vasovagal syncope

Answer 14

large increase in parasympathetic output (decrease CO) and reduction in sympathetic output (large decrease in peripheral resistance) decrease arterial pressure

Question 15

bulk flow

Answer 15

mass movement of fluid of hydrostatic or osmotic pressure gradient

• pressure blood exerts on vessel wall

Question 16

absorption

Answer 16

fluid moving into capillaries

Question 17

filtration

Answer 17

fluid moving out of capillaries

Question 18

hydrostatic pressure

Answer 18

pressure of blood vessels drives fluid out of the capillaries through pores and cell juncitons (filtration)

Question 19

colloid osmotic pressure

Answer 19

pressure that draws fluid into capillaries is the pressure created by plasma proteins in the blood

Question 20

Capillary filtration and absorption

Answer 20

arterial side, net filtration

venous side, absorption

Question 21

formation of plaque

Answer 21

• LDL is taken up by arteries
• macrophages become cells
• release of cytokinases starts the formation of plaque
• smooth muslce cells divide and build up
• calcium build up
• macrophages may release enzymes that dissolve collagen and convert stable plaques to unstable plaques
• platelets that are exposed to collagen forms blood clot