Blood vessels

Question 1

What are the 3 main type of blood vessels?

Answer 1

Arteries
Veins
Capillaries

Question 2

How can you identify a capillary

Answer 2

Single cell
Thick wall

Question 3

How can you identify an artery

Answer 3

It has the thickest muscular wall
Narrow lumen

Question 4

How can you identify a vein

Answer 4

largest lumen

Question 5

what is the role of the veins

Answer 5

take blood to the heart

Question 6

what is the role of the arteries

Answer 6

takes blood away from the heart

Question 7

what is the role of arterioles

Answer 7

controls blood flow from arteries to capillaries

Question 8

what is the role of venules

Answer 8

carrier blood flow from the capillaries to the veins

Question 9

what is the role of capillaries

Answer 9

links arterioles to veins where exchange takes place

Question 10

What is the general structure of blood vessels

Answer 10

Tough outer layer
Muscle layer
Elastic layer
Lining layer (endothelium)
Lumen

Question 11

What is the function of the touch outer layer

Answer 11

Resists pressure changes from within and outside

Question 12

what is the function of the muscle layer?

Answer 12

can contract and help blood flow

Question 13

what is the function of the elastic layer?

Answer 13

can stretch and recoil - helps maintain blood pressure

Question 14

what is the function of the lining layer (endothelium)?

Answer 14

smooth to prevent friction

Question 15

what is the function of the lumen?

Answer 15

central cavity through which blood flows

Question 16

what type of blood do the arteries carry

Answer 16

they carry oxygenated blood (except pulmonary artery) away from the heart

Question 17

what type of blood do veins carry?

Answer 17

carries deoxygenated blood back to the heart except pulmonary vein

Question 18

what type of blood do the capillaries carry?

Answer 18

becoming deoxygenated
direction if blood : between artery and vein

Question 19

What is the pressure of blood in the arteries

Answer 19

high pressure

Question 20

what is the pressure of blood in the veins ?

Answer 20

low pressure

Question 21

do the arteries have elastic tissues

Answer 21

yes
thick layer

Question 22

do the veins have elastic tissue

Answer 22

yes
thin layer

Question 23

do the arteries e have valves ?

Answer 23

only aortic and pulmonary

Question 24

do the arteries have a large or small lumen

Answer 24

small

Question 25

do the veins have a large or small lumen

Answer 25

large so despite low pressure, blood flows back to heart at the same rate it leaves

Question 26

What happens to the arteries when the valves are open

Answer 26

The left ventricle contracts Blood moves into the septa Pressure in aorta increases Elastic fibres stretch to allow for increase in volume and pressure

Question 27

What happens to the arteries when the valves are closed

Answer 27

Left ventricle relaxes pressure decreases elastic fibres recoil smooth blood flow and high pressure maintained

Question 28

What are arterioles

Answer 28

smaller than arteries blood at lower pressure rhan arteries less elastic tissue more smooth muscle smooth muscle contracts / relaxes to control flow of blood

Question 29

what is the function of capillaries

Answer 29

exchange metabolic materials including oxygen carbon dioxide glucose between blood and cells

Question 30

do the veins have valves

Answer 30

yes semi-lunar valves : ensure blood flows in 1 direction toward heart

Question 32

what are the benefits of the capillaries having a narrow diameter

Answer 32

high frictional resistance slow blood flow more time for exchange

Question 33

What is vasoconstriction

Answer 33

vessel - constrict (narrowing)

Question 34

What happens with vasoconstriction

Answer 34

Contraction of smooth muscle narrows arteriole (smaller lumen) This decreases the blood flow to capillaries eg when cold - less blood to skin to minimise heat loss

Question 35

What is vasodilation

Answer 35

vessel - dilate/wider

Question 36

What happens with vasodilation

Answer 36

relaxation of smooth muscle widens arteriole (larger lumen) Increased blood flow to capillaries eg when hot more blood to skin to maximise heat loss

Question 37

How do capillaries increase the time for exchange

Answer 37

red blood cells regale in a single file -> slows blood flow -> more time for exchange

Question 38

How do capillaries decrease the diffusion pathway

Answer 38

the red blood cells are squeezed flat against the capillary wall

Question 39

What is venous return

Answer 39

The flow of blood back to the heart

Question 40

what does venous return mean

Answer 40

when u exercise, the amount of blood returning to the heart (venous return) increases so if more blood is being pumped back to the heart then more blood has to be pumped out so stroke volume increases

Question 41

what causes the valves to close

Answer 41

blood flowing away from the heart pushes the flaps of the valves closed

Question 42

What are varicose veins

Answer 42

valves in veins don’t function weak vein wall back flow of blood lumps in legs