Lesson 20: Topic 16 - Intro to Vascular

Question 1

what are the functions of the vascular system?

Answer 1

• delivery of O2 (most important)
• removal of CO2
• nutrient delivery
• removal of waste
• distribution of hormones
• transport of immune cells
• temperature control

Question 2

why does CO2 need to be removed from the body?

Answer 2

it can impede basal function due to acidosis

Question 3

what is selective distribution of the vascular system?

Answer 3

• not all tissues receive equal blood volumes

Question 4

at rest, what percentage of our blood goes to skeletal muscle?

Answer 4

15%

Question 5

when we exercise, our blood percentage distribution to each organ changes. what has the most significant increase?

Answer 5

the skeletal muscle
- percentage depends on intensity and duration of exercise

Question 6

what is the components of the vascular network?

Answer 6

1. pulmonary circulation
2. systemic circulation

Question 7

what is the pulmonary circulation?

Answer 7

from the heart to the lungs

Question 8

what is the systemic circulation?

Answer 8

from the heart to all other tissues except the lungs

Question 9

is the aorta a vein or artery?

Answer 9

artery

Question 10

which blood vessels carry oxygenated blood?

Answer 10

pulmonary veins and systemic arteries

Question 11

which blood vessels carry deoxygenated blood?

Answer 11

pulmonary arteries and veins

Question 12

what is macro-circulation?

Answer 12

takes blood to or from organs
ex. arteries and veins

Question 13

what is micro-circulation?

Answer 13

distributes blood within each organ
ex. arterioles and venules and capillaries

Question 14

what type of cell forms the inner layers of ALL blood vessels?

Answer 14

endothelial cells

Question 15

what are the layers of an artery?

Answer 15

from inner to outer:
- endothelium
- basement membrane
- elastic fibres
- smooth muscle
- elastic fibres
- connective tissue coat (mostly collagen fibres)

Question 16

what are the layers of an arteriole?

Answer 16

• endothelium
• basement membrane
• smooth muscle
• connective tissue coat (mostly collagen fibres)
• same as artery except they do not have elastic fibres

Question 17

why does arteries have thick elastic walls?

Answer 17

to withstand high pressure

Question 18

what is the thickest layer in both the arteries and the arterioles?

Answer 18

smooth muscle

Question 19

the muscular walls of an arteriole control?

Answer 19

blood flow (ie, control valves for capillary beds) to tissues

Question 20

the thin walls of capillaries allow for?

Answer 20

exchange of gases, nutrients, fluids

Question 21

what are the two wall layers of a capillary?

Answer 21

• endothelium
• basement membrane

Question 22

what are the wall layers of a vein?

Answer 22

• endothelium
• basement membrane
• smooth muscle; elastic fibres
• connective tissue coat (mostly collagen fibres)

Question 23

veins have thin walls compared to?

Answer 23

arteries

Question 24

what is the pressure system like in veins?

Answer 24

low pressure system

Question 25

why does veins have a low pressure system?

Answer 25

because blood in the veins comes from blood in the arteries that passed through the tissues so the pressure is lost and distributed

Question 26

how are veins a blood reservoir (reserver?)?

Answer 26

because the have venous valves to keep blood

Question 27

what is the thickest layer of wall in the vein?

Answer 27

smooth muscle

Question 28

do veins have a lot of elastic fiber?

Answer 28

they have very little (it is there thinnest layer)

Question 29

what is the thinnest wall layer of an arteriole?

Answer 29

the collagen fibers

Question 30

does arteries have a thick elastic fibre layer?

Answer 30

yes, they have two

Question 31

what is the equation for flow?

Answer 31

flow = Pressure / resistance

Question 32

** ** ** how can flow be related to cardiac output?

Answer 32

cardiac output = (mean arterial pressure - right arterial pressure) / total peripheral resistance - HOWEVER, right atrial pressure typically = very close to 0 - SO - CO = MAP / TPR ***********

Question 33

does absolute pressure determine blood flow?

Answer 33

no. only pressure gradient - the pressure GRADIENT along the length of the tube determines blood flow

Question 34

does pressure increase or decrease as it goes from left ventricle to arteries, to arterioles, to capillaries to venules and veins?

Answer 34

decreases

Question 35

does the pressure in arteries ever go to 0?

Answer 35

no, there is always blood in arteries so they will always have a pressure

Question 36

what is the diastolic pressure in the aorta?

Answer 36

about 80 mmHg

Question 37

what is the diastolic pressure in the left ventricle?

Answer 37

about 0 mmHg

Question 38

is there a continuous or discrete pressure gradient from arteries to veins?

Answer 38

continuous

Question 39

where does the largest pressure drop across blood vessels happen?

Answer 39

largest pressure drop at the level of the arterioles

Question 40

if diastolic blood pressure is 80mm Hg in a systolic heart failure patient, what would be the pressure gradient in the aorta if systolic blood pressure reached 80mm Hg?

Answer 40

0mm Hg - this is because diastolic BP is the lowest and systolic BP is the highest so 80 - 80 = 0mm Hg