circulatory system

Question 1

coronary heart disease:

Answer 1

• hearts blood supply gets blocked
• in the coronary artery (supplies heart muscle with blood)
  -> blood supply gets restricted by fatty deposits in the wall of the artery
  -> lumen comes narrower
  -> restricted blood supply as not enough blood is reaching the heart muscle
  -> less O2 means less aerobic respiration -> more lactic acid, which poisons heart muscles leading to a heart attack

Question 2

what can increase your chance of coronary heart disease

Answer 2

• smoking
• eating too much saturated fat
• obesity
• inactivity
• high blood pressure
• stress

Question 3

what causes an increase in heart rate

Answer 3

• nerve impulses from the medulla
• when we exercise more carbon dioxide is produced
• sensors in the aorta and carotid artery detect this
• send nerve impulses to the medulla
• medulla sends nerve impulses to the heart via the accelerator nerve, causing the heart rate to increase and the heart will beat with more force (higher blood pressure)
• once carbon dioxide levels return to normal, nerve impulse are sent via decelerator nerve to decrease heart rate and bring blood pressure back to normal

Question 4

blood direction in arteries

Answer 4

away from the heart

Question 5

blood direction in veins

Answer 5

to the heart

Question 6

blood direction in capillaries

Answer 6

to organs and muscles

Question 7

is blood oxygenated or deoxygenated in arteries

Answer 7

oxygenated

(except for the pulmonary artery)

Question 8

is blood oxygenated or deoxygenated in veins

Answer 8

deoxygenated

(except for the pulmonary vein)

Question 9

is blood oxygenated or deoxygenated in capillaries

Answer 9

at artery end its oxygenated

at vein end it’s deoxygenated

Question 10

blood pressure in arteries

Answer 10

high

Question 11

blood pressure in veins

Answer 11

low

Question 12

blood pressure in capillaries

Answer 12

high -> low

(needs to reduce pressure)

Question 13

wall thickness in arteries

Answer 13

thick muscular wall (can stretch) to resist bursting under pressure

Question 14

wall thickness in veins

Answer 14

thin

Question 15

wall thickness in capillaries

Answer 15

thin
-> short diffusion distance

Question 16

internal diameter (lumen) in arteries

Answer 16

small -> help keep pressure of blood

Question 17

internal diameter (lumen) of veins

Answer 17

large -> reduces blood pressure

Question 18

internal diameter (lumen) of capillaries

Answer 18

really small
so it can fit between cells and organs

Question 19

valves present in arteries?

Answer 19

no
-> blood is pumped at such a high pressure

Question 20

valves present in veins?

Answer 20

yes

Question 21

valves present in capillaries

Answer 21

no

Question 22

example of an artery

Answer 22

aorta

Question 23

example of a vein

Answer 23

vena cava

Question 24

example of capillary

Answer 24

capillary at alveoli

Question 25

elastic layer thickness in arteries

Answer 25

thick elastic layer

Question 26

elastic layer thickness in veins

Answer 26

thin elastic layer

Question 27

function of artery

Answer 27

transport blood away form the heart

Question 28

function of vein

Answer 28

transport blood to the heart

Question 29

function of capillaries

Answer 29

carry blood to the bodies cells