arteries, veins & capillaries

Question 1

where do arteries carry blood to?

Answer 1

away from the heart

Question 2

what is the blood like in arteries?

Answer 2

flowing at high pressure

Question 3

where do veins carry blood to?

Answer 3

return blood into the heart

Question 4

what is the blood like in veins?

Answer 4

flowing at low pressure

Question 5

what are capillaries?

Answer 5

tiny vesselsa

Question 6

are there a lot of capillaries?

Answer 6

yes

Question 7

where do capillaries carry blood through?

Answer 7

they carry blood through all the tissues

Question 8

what are capillaries the site of?

Answer 8

the site of exchange of materials by diffusion

Question 9

arteries:
wall?
lumen?
muscles & elastic fibres?

Answer 9

• thick outer wall
• small lumen
• thick layer of muscles & elastic fibres

Question 10

what is the function of the artery’s thick outer wall?

Answer 10

can transport blood at high pressure without bursting

Question 11

what is the function of the artery’s thick layer of elastic tissue?

Answer 11

allows the artery to stretch & recoil to keep blood flowing at high pressure

Question 12

what is the function of the artery’s thick layer of muscular wall?

Answer 12

helps to control flow of blood by widening (dilating) and narrowing (constricting)

Question 13

what are arterioles?

Answer 13

smaller vessels that branch off from arteries

Question 14

what are venules?

Answer 14

small veins

Question 15

why type of blood do arteries carry?

Answer 15

oxygenated blood

Question 16

what artery carries deoxygenated blood?

Answer 16

pulmonary artery

Question 17

at what speed does blood flow through arteries?

Answer 17

at a fast speed

Question 18

what also helps arteries to maintain high pressure?

Answer 18

a narrow lumen

Question 19

veins:
wall?
lumen size?
muscle & elastic fibres?

Answer 19

• fairly thin outer wall
• large lumen
• thin layer of muscle & elastic fibres

Question 20

what type of blood do veins carry?

Answer 20

deoxygenated blood

Question 21

what type of blood does the pulmonary vein carry?

Answer 21

oxygenated blood

Question 22

veins contain…

Answer 22

semilunar valves

Question 23

at what speed does blood flow through veins?

Answer 23

at a slow speed

Question 24

what does a large lumen do for the veins?

Answer 24

reduces resistance to blood flow under low pressure

Question 25

what do the semilunar valves do?

Answer 25

the backflow of blood as it is under low pressure

Question 26

why do veins have a fairly thin outer wall?

Answer 26

blood is flowing at lower pressure so a thick wall is not needed

Question 27

capillaries:
wall?
lumen?

Answer 27

• wall made of a singer layer of cell
• very small lumen

Question 28

what type of pressure do capillaries carry blood at?

Answer 28

carry blood at low pressure within tissues

Question 29

what type of blood do capillaries carry?

Answer 29

both deoxygenated and oxygenated blood

Question 30

in capillaries the wall is only one cell thick- what does this mean?

Answer 30

• short diffusion distance
• substances can easily diffuse in and out of them

Question 31

what do the “leaky” walls in capillaries do?

Answer 31

allow blood plasma to leak out & form tissue fluid surrounding cells

Question 32

what happens to arteries if they get further away from the heart?

Answer 32

they divide more and get narrower

Question 32

what are the narrow vessels that connect arteries to capillaries called?

Answer 32

arterioles

Question 33

what happens to veins as they get further away from the heart?

Answer 33

they get narrower

Question 34

what are the narrow vessels that connect capillaries to veins called?

Answer 34

venules