Circulatory System Flashcards Preview

NBDE PART 1 BIOCHEM/PHYSIOLOGY > Circulatory System > Flashcards

Flashcards in Circulatory System Deck (78):
1

what has the thickest layer of muscle:
veins/arteries/capillaries/arterioles/venules

arteries

2

which is the major regulator of blood flow
veins/arteries/capillaries/arterioles/venules

arterioles

3

which contains valves
veins/arteries/capillaries/arterioles/venules

veins

4

which has higher compliance veins or arteries

veins

5

the only arteries that contain deoxygenated blood are

pulmonary artery and umbilical artery

6

all arteries carry blood which way

away from the heart

7

_ transport deoxygenated blood from the tissue back to the heart

veins

8

the only veins that contain oxygenated blood

pulmonary vein and umbilical vein

9

veins always take blood where

to the heart

10

what is compliance

Compliance is the ability of a hollow organ (vessel) to distend and increase volume with increasing pressure or the tendency of a hollow organ to resist recoil toward its original dimensions on application of a distending or compressing force

11

compliance formula is

c = delta v/delta p

12

where does exchange of fluid/nutrients and waste occur

capillaries

13

the capillary walls are vey thin made of

one single layer of endothelial cells surrounded by a basal lamina of tunica intima

14

___ are very small veins that collect blood from capillaries

venules = gradually coalesce into progressively larger veins

15

what vein brings blood from head and trunk

superior vena cava

16

what vein brings blood from lower extremities

inferior vena cava

17

the elastic arteries are the

large and medium arteries

18

the muscular arteries are the

small arteries/arterioles = these will vasoconstrict!!!! that is why they are the blood flow regulators!!

19

large artery ==> medium artery ==> small arteries ==> arterioles ==> capillaries ==> venules ==> veins.

at any one time where is 2/3 of your blood located in the scheme above?

veins or venules!! therefore they deal with large volumes of blood. vs arteries which deal with high pressures.

this is why Compliance = delta V/delta P is higher in veins!!!

20

the highest resistance in cardiovascular system is where
large artery ==> medium artery ==> small arteries ==> arterioles ==> capillaries ==> venules ==> veins.

arterioles

21

the __ are the last small branches of the arterial system

arterioles

22

arterioles act as control valves thru which blood is released into the capillaries. any ARTERY smaller than __mm in diameter is an arteriole

0.5mm

23

1. arterioles have a thick/thin tunica media that is composed almost entirely of __
2. does it have a lot of elastic tissue

1. thick, smooth muscle
2. no. it has very little elastic tissues

24

the __ of an arteriole is composed of endothelial cells lying on a BM with an underlying fine internal elastic lamina in the larger arterioles

intima

25

_ are the primary resistance vessels and determine the distribution of cardiac output

arterioles

26

what is the splanchnic circulation

includes most of the structures usually considered "internal organs", but not all (for example, the heart is excluded

27

arteriole resistance is regulated by __ receptors found in the skin and splanchnic circulation

alpha-1-adrenergic

28

__ receptors are found on arterioles of skeletal muscle

Beta-2 adergenergic

29

_ receptors are found in the heart muscle and the kidneys

beta-1 adergenergic

30

indicate if vasoconstrictor or dilator
1. endothelins
2. nitric oxide
3. adenosine

1. constrict
2. dilate
3. dilate

31

Endothelins

proteins that constrict blood vessels and raise blood pressure

32

α1-receptors primarily mediate ___ muscle contraction.

smooth

33

α1-receptors in smooth muscle will result in ___. Blood vessels with α1-adrenergic receptors are present in the skin, the sphincters[2] of gastrointestinal system, kidney (renal artery)[3] and brain

vasoconstriction

34

which circuit supplies the alveoli of the lungs
pulmonary circuit/systemic circuit/neither/both

pulmonary circuit

35

which circuit supplies the CT of the lungs?
pulmonary circuit/systemic circuit/neither/both

systemic

36

which has a lower blood pressure?
pulmonary circuit/systemic circuit/neither/both

pulmonary

37

which has a greater volume of blood flow per minute?
pulmonary circuit/systemic circuit/neither/both

neither

38

which circuit involves the thick walled left ventricle

systemic

39

the pump for the pulmonary circuit is the

right ventricle

40

the pump for the systemic circuit is the

left ventricle

41

the vessels of the pulmonary circuit supply ONLY THE

lung alveoli

42

the systemic circuit provides blood to ALL BODY TISSUES. except for the

alveoli of the lungs

43

the volume of blood flow per minute is ___ and is the __ in the circuits

5L/min
SAME in both circuits

44

mean arterial blood pressure can be calculated with what equation

BP = CO x TPR

45

Vascular compliance =

increase in volume/increase in pressure

46

pulmonary arterioles are usually dilated and have ___ resistance to blood flow

little

47

the pulmonary vessels are high/low compliant

HIGHLY COMPLIANT = allows the pulmonary circuit to store blood volume w/o changing blood pressure

48

compliance will __ at higher pressure and volumes

decrease

49

at higher pressure and volumes, venous compliance becomes similar to

arterial compliance = this is why veins are suitable for use as arterial by-pass grafts

50

veins can accommodate large changes in __ with only a small change in __

large change in volume
small change in pressure = high compliance

51

place in order of blood volumes while at rest: in the heart, in the capillaries, in the pulmonary loop, in the systemic arteries and arterioles, in the systemic veins and venules

systemic veins and venules (66%)
in the pulmonary loop (12%)
in the systemic arteries and arterioles (11%)
in the heart 6%
in the capillaries = 5%

52

the most amount of blood is in the __ and the least are in the _

most veins/venules
least in capillaries

53

your patient presents with stage 1 hypertension. his blood pressure is 150/99 mmHg. is his pulse pressure normal high or low

high

54

the pulse pressure =

systolic blood pressure - diastolic blood pressure

55

the most important determinant in pulse pressure is

stroke volume

56

a positive net pressure number means

filtration will occur

57

a negative net pressure number means

absorption will occur

58

1. where are our baroreceptors in our circulation
2. these receptors detect change in blood pressure and relay that info to the

1. carotid sinuses and in the arch of the aorta
2. cardiac control center and the vasomotor center in the medulla which alter the ratio of sympathetic and parasympathetic impulses

59

if the blood pressure is too high, __ impulses will dominate and reduce the pressure by slowing the heart rate, reducing stroke volume and dilating the blood reservoir vessels

parasympathetic

60

if blood pressure is too low, __ impulses will dominate and reduce the pressure by increasing the heart rate, stroke volume and constricting the blood reservoir vessels

sympathetic impulses

61

stretch receptors in the carotid sinus are stimulated by ___

elevated blood pressure = they will activate the PNS and inhibit the SNS to reduce the BP back to set point

62

chemoreceptors in the carotid and aortic bodies and chemoreceptors neurons in the vasomotor center of medulla detect increases in what and decreases in what?

increase in CO2, decrease in blood O2 and decrease in pH (H ion concentration)

63

if CO2 increases/pH drops or oxygen drops the __ impulses dominate

sympathetic = increase heart rate, stroke volume and constricts vessels

64

atria and pulmonary stretch receptors are stimulated by ____

expansion of blood volume. NOT TO CHANGES IN ARTERIAL BLOOD PRESSURE

65

name the layers in arteries

tunica adventitia > tunica media > tunica intima (inner most)

66

what is the toughest vessel to puncture? vein artery or capillary

artery

67

which layer is thicker tunica media or tunica adventitia

media

68

which layer is innervated by autonomic nervous system
tunica adventitia/tunica media/tunica intima

media

69

by puncturing the artery you have hit the vessel with the greatest:
a. resistance
b. pressure
c. cross-sectional area
d. blood volume

pressure

70

Which has the highest pressure:
arteries/arterioles/capillaries/veins

arteries

71

which has the largest resistance
arteries/arterioles/capillaries/veins

arterioles

72

which has the largest blood volume
arteries/arterioles/capillaries/veins

veins

73

which has the largest cross sectional area
arteries/arterioles/capillaries/veins

capillaries

74

in the arteries which is thicker the tunica adventitia or the tunica media

tunica media

75

in the veins which is thicker the tunica media or adventitia

adventitia

76

in capillaries which tunicas are present/absent

ONLY has tunica intima (endothelium)

77

tunica ___ is made of fibrous CT

adventitia

78

tunica __ is made of smooth muscle and elastic CT

media