EX 2: The Vascular System Flashcards Preview

AU14 Physiology > EX 2: The Vascular System > Flashcards

Flashcards in EX 2: The Vascular System Deck (57):
1

These are the main transporters of oxygenated blood

arteries

2

In these, the diameter is adjusted to regulate blood flow

arterioles

3

There is where diffusion occurs across thin walls

capillaries

4

What are three functions of the endothelial cell monolayer of capillariers

physical lining
permeable barrier for exchange
secrete paracrine agents that induce vasodilation or vasoconstriction

5

Pulses of pressure move throughout the vasculature decreasing in what with distance

amplitude

6

What is the maximum arterials pressure

systolic pressure

7

What is the minimum arterial pressure

diastolic pressure

8

What is pulse pressure

systolic pressure - diastolic pressure

9

What three things is pulse pressure determined by

stroke volume
speed of ejection of the stroke volume
arterial compliance (resist recoil)

10

What is the equation for compliance

change in volume
divided by
change in pressure

11

What is the long equation of MAP

DP + 1/3(SP+DP)
spend most of our time in diastole, only 1/3 in systole

12

The blood moved in a
single heart contraction
stretches out the arteries,
so what happens during diastole

their recoil
continues to push
on the blood, keeping it
moving during diastole.

13

This is the pressure driving blood into the tissues averaged over the cardiac cycle

MAP

14

In arterioles, the flow of an organ equals what

MAP/resistance of the organ

15

The smooth muscle cells of the arterioles can do what two things

relax
contract

16

Dynamic adjustments in the blood distribution to the organs is accomplished by what

relaxation and contraction of circular smooth muscle in the arterioles

17

The intrinsic tone of the arterioles is controlled by what two things

local controls
extrinsic controls

18

Active hyperemia and flow autoregulation differ in their cause but both result in what

the production of the same local signals that provoke vasodilation

19

What would happen with decreased metabolic activity or increase arterial pressure?

If you decrease MAP you will decrease flow to 2 different organs, unless you change resistance

20

In active hyperemia, an increase in metabolites in organ interstitial fluid and a decrease in O2 will have what affect

vasodilation

21

In flow autoregulation, a decrease in O2 and an increase in metabolites of an organ will cause what

vasodilation

22

What two things control the intrinsic tone of the arterioles

local controls; active hyperemia and flow autoregulation

23

This is the accumulation of Co2, H, K, eicosanoids, adenosine, bradykinin, and NO. Which controls intrinsic control of the arterioles

active hyperemia

24

What are the two responses of flow autoregulation

myogenic response
reactive hyperemia

25

This is when some arteriolar smooth muscle responds to increase stretch caused by an increased pressure by contracting to a greater extent

myogenic response (flow autoregulation

26

This the response to cessation of blood flow

reactive hypermia (flow autoregulation)

27

Sympathetic stimulation (NE) of these receptors causes vasoconstriction to decrease blood flow to that location

alpha-adrenergic

28

Sympathetic stimulation (E) of these receptors leads to vasodilation to cause an increase in blood flow to that location

beta-adrenergic

29

Where are the alpha receptors located

vessels

30

Where are beta receptors located

atraia and ventricles

31

What are the four extrinsic controls of the arterioles

sympathetic nerves
parasympathetic nerves
non-cholinergic, non-adrenergic autonomic neurons
hormones

32

What are the two paracrine effects of the arterioles

vasodilators
vasoconstrictors

33

What are two vasodilators with paracrine function

endothelium derived relaxing factor; EDRF
prostacyclin

34

What is a vasoconstrictor with paracrine effects

endothelin-1

35

What are the two endothelial controls on the arterioles

paracrine effects
flow induced arterial vasodilation

36

Diversity among signals that influence contraction/relaxation in circular smooth muscle implies what

a diversity of receptors and transduction mechanisms

37

What are the two locally controlled organs

brain and heart

38

What are four the neurally controlled organs

skin
muscle
GI
kidney

39

When do the skin and muscles become under local control

when exercising

40

Capillaries lack this

smooth muscle

41

What detrained the volume of blood each capillary receives

contraction/relaxation of circular smooth muscles in upstream met arterioles and pre-capillary sphincters

42

There are many, many capillaries, each with slow-moving blood in it, resulting in what

adequate time and surface area for exchange between the capillary blood and ISF

43

This is the movement of fluid and solutes out of the blood

filtration

44

This is the movement of fluid and solutes into the blood

absorption

45

These two things favor fluid movement out of the capillary

capillary hydrostatic pressure (PC)
osmotic force due to interstitial fluid protein concentration (Ħif)

46

These two things favor movement into the capillary

interstitial hydrostatic pressure (Pif)
osmotic forse due to plasma protein concentration (Ħc

47

These are low molecular weight penetrating solutes

crystalloids

48

These are non-penetrating plasma proteins

colloids

49

What is the net filtration pressure equation

Pc + Ħif - Pf - Ħc

50

If an accident victim loses 1L of blood, why would IV injection of plasma be more effective for replacing the lost volume

protein gets into capillaries therefore keeping the water in the capillaries

51

At rest, approximately what percentage of the total blood volume is in the veins

60%

52

This can substantially increase venous return to the heart

sympathetically mediated venoconstiriction

53

Venus flow is assisted by what

the skeletal muscle pump mechanism working in combination with one-way valves

54

Alterations in "venous return" can alter what

end-diastolic volume

55

An increase in EDV directly increases what

stroke volume and cardiac output

56

This is formed by the slight mismatch between filtration and absorption in the capillaries, returns the blood in the veins

lymphatic fluid

57

What three things can cause abnormalities of the lymphatic system

congenital traumatic or infectious etiologies