circulatory system-blood vessels

Question 1

why do arteries have thick walls?

Answer 1

to withstand pressure

Question 2

direction of blood flow for all

Answer 2

a-away from heart
v-to heart
c-arteries to veins

Question 3

why do capillaries have one cell thick walls?

Answer 3

so the walls are permeable and to decrease diffusion distance, increasing rate of diffusion

Question 4

why do veins have thin walls?

Answer 4

they only carry low pressure blood

Question 5

what are arteries made of and why?

Answer 5

muscular walls to make them strong to resist high pressure, elastic fibres that stretch when the surge of blood passes through and then recoil in between to keep blood flowing and withstand high pressure

Question 6

how does blood travel in veins and arteries?

Answer 6

veins-smoothly
arteries-in surges, when the heart beats

Question 7

what diffuses in and out of capillaries?

Answer 7

food in and waste products out

Question 8

what do arteries branch into?

Answer 8

capillaries

Question 9

what do capillaries join to form?

Answer 9

veins

Question 10

what do capillaries do?

Answer 10

carry blood close to every cell to exchange substances

Question 11

why do veins have the biggest lumen?

Answer 11

to help blood flow, enable low pressure

Question 12

why do veins have valves?

Answer 12

blood moves slow with low pressure so valves keep it flowing in the right direction and prevent its backflow

Question 13

capillaries

Answer 13

carry blood through the body tissues, allowing oxygen, nutrients, and waste products, to be exchanged between tissues and the blood

Question 14

give 2 nutrients that are exchanged between the blood in the capillaries

Answer 14

amino acids
glucose

Question 15

give 2 waste products that are exchanged

Answer 15

carbon dioxide
urea

Question 16

what is the only artery that doesn’t carry oxygenated blood?

Answer 16

plumonary

Question 17

which is the only vein that carries oxygenated blood?

Answer 17

pulmonary

Question 18

3 types of blood vessels

Answer 18

-arteries
-veins
-capillaries

Question 19

function of arteries

Answer 19

carry blood away from heart

Question 20

function of veins

Answer 20

carry blood towards heart

Question 21

function of capillaries

Answer 21

enable transfer or substances between the blood and tissues

Question 22

why do capillaries have a narrow lumen?

Answer 22

blood moves slowly meaning more time for diffusion

Question 23

how do you calculate the rate of blood flow?

Answer 23

volume of blood/number of minutes

Question 24

two ways arteries are adapted for their function

Answer 24

-thick muscle layer
-thick elastic layer

Question 25

three ways capillaries are adapted for their function

Answer 25

-walls one cell thick
-walls permeable
-narrow lumen

Question 26

two ways veins are adapted for their function

Answer 26

-wide lumen
-valves