L7

Question 1

what is the role of the circulatory system

Answer 1

to provide O2/nutrients to every cell in the body and remove CO2/waste products from every cell in the body

Question 2

what are the 2 things that the circulatory system requires

Answer 2

a driving force i.e. pump = heart

conduit system = vascular bed

Question 3

what is the vascular bed

Answer 3

capillaries

Question 4

what are the 2 juxtaposed systems in the heart

Answer 4

systemic and pulmonary circulation

Question 5

describe the systemic circuit

Answer 5

from the left side of the heart, around the body, and back into the right side of the heart

Question 6

describe the pulmonary circuit

Answer 6

the right ventricle to the lungs and back to the left side of the heart

Question 7

what is the route blood takes in the systemic circuit

Answer 7

left ventricle -> aorta -> arteries -> arterioles -> capillaries -> venules -> veins -> vena cava _ right atrium and ventricle

Question 8

what kind of circuit is the systemic circuit

Answer 8

parallel

Question 9

what is the route blood takes in the pulmonary circuit

Answer 9

right ventricle -> pulmonary artery -> arterioles -> capillaries -> venules -> pulmonary veins -> left atrium and ventricle

Question 10

what kind of circuit is the pulmonary circuit

Answer 10

series as 100% of the CO ges through pulmonary circulation

Question 11

what structures are in the delivery system

Answer 11

arteries, arterioles and capillaries

Question 12

what structures are in the waste removal system

Answer 12

venules and veins

Question 13

the different blood vessels are made up of a range of different tissues. what layer do all the blood vessels have

Answer 13

an endothelial cell layer

Question 14

what makes up the microvasculature

Answer 14

The terminal arterioles, capillaries and the small venules

Question 15

describe the structure of the capillaries

Answer 15

The capillaries have an endothelial cell layer and a basement membrane
It only having that one cell layer means that there is a really small diffusion distance

Question 16

what is blood flow

Answer 16

CO

Question 17

what is flow dependent on

Answer 17

Q = pressure difference / resistance

Question 18

what is the poiseuille relationship

Answer 18

it relates pressure, radius and viscosity to blood flow

Question 19

if you increase the length of the vessel what happens to the resistance

Answer 19

it increases

Question 20

what could be a reason where the viscosity of the blood could increase

Answer 20

if you were severally dehydrated

this increase in viscosity could increase resistance

Question 21

what happens to the cross sectional area of the individual vessels as you travel towards the capillaries

what does this mean in terms of resistance

Answer 21

The cross sectional area get smaller and smaller as you go towards the capillaries and away from the aorta meaning that resistance increases

Question 22

what happens to the TOTAL cross sectional area of the individual vessels as you travel towards the capillaries

Answer 22

the capillaries have the largest net cross sectional area

Question 23

if the capillaries have the largest total cross sectional area how come the blood is stored in the veins

Answer 23

because veins are compliance vessels

Question 24

what does cross sectional area have to do with velocity

Answer 24

Large CSA the velocity is low

Low CSA –> Velocity to increase

The flow in terms of volume is the same but the area has increased (capillaries) therefore velocity decreases

Question 25

when looking at the pressure of the systemic arterial network, where will you see a large pressure drop

Answer 25

the arterioles

Question 26

what features of the capillaries make them perfect for exchange

Answer 26

Large capillary network =
large cross sectional area

Capillaries thin wall =
small diffusion distance

Low velocity =
time for diffusion

Non-Pulsatile flow =
continuous blood movement

Question 27

what happens to blood flow in the venous system

Answer 27

total CSA goes down therefore velocity goes up

Although the CSA goes down the pressure is not going to go up because of the distance from the heart

Question 28

where is the pressure lowest

Answer 28

in the right atrium

Question 29

describe the pulmonary circuit

Answer 29

Branching towards
capillaries then decreased
again on way back to heart

Similar effects on the CSA
and velocity

Blood pressure much lower!

Decreasing pulsatile flow
Low pressure circuit

Question 30

the pulmonary circuit is a ________ circuit

Answer 30

low pressure

Question 31

What is the correct blood flow order through the pulmonary system starting at the vena cava

A: LA, LV, pulmonary artery, capillaries,
pulmonary vein, RA, RV, aorta

B: RA, RV, pulmonary vein, capillaries,
pulmonary artery, LA, LV, aorta

C: RA, RV, pulmonary artery, capillaries,
pulmonary vein, LA, LV, aorta

D: RV, RA, pulmonary artery, capillaries,
pulmonary vein, LA, LV, aorta

Answer 31

C

Question 32

The resistance to blood flow through the arterioles is higher than in the aorta BECAUSE
resistance is proportional to radius^4 .

Answer 32

The first is true and the second is false

because it should say inversely proportional

Question 33

Which of the following is not a type of blood vessel?

A: Artery

B: Vein

C: Ventricle

D: Venule

Answer 33

C

Question 34

If a blood vessel decreased in radius by 3 times, the resistance would _____ by a factor of _______?

A: Decrease; 81

B: Increase; 81

C: Decrease; 12

D: Increase; 12

Answer 34

B

Question 35

The velocity of blood flow is slowest through the capillaries

BECAUSE

the cross sectional area of the individual capillary is the smallest.

Answer 35

both are true but not causal

Question 36

Blood flow in the pulmonary vein is pulsatile

BECAUSE

the blood only exits the right ventricle into the pulmonary circulation during systole.

Answer 36

the first statement is false but the second statement is true