the heart

Question 1

what is the role of the heart

Answer 1

to pump oxygenated blood around the body to cells so respiration can take place

Question 2

what is the heart made of

Answer 2

cardiac tissue

Question 3

what does the heart need so it can contract

Answer 3

oxygen and glucose

Question 4

how is the heart supplied with oxygen and glucose

Answer 4

by the coronary arteries

Question 5

what does VAVA VAVA stand for

Answer 5

Vena cava
Atrium (right)
Ventricle (right)
Artery (pulmonary)

Vein (pulmonary)
Atrium (left)
Ventricle (left)
Aorta

Question 6

which ventricle has a thicker wall

Answer 6

left

Question 7

what is the role of the valves

Answer 7

preventing backflow in the heart between pumps

Question 8

why is it important to prevent backflow

Answer 8

maximise the amount of oxygenated blood reaching the body as valves make the heart more efficient

Question 9

what do the 2 circuits do in a double circulatory system

Answer 9

one pumps deoxygenated blood to the lungs
the other pumps the oxygenated blood around the body

Question 10

why is a double circulatory system good

Answer 10

it is more efficient as it separates the oxygenated and deoxygenated blood
it allows for higher pressure in the systemic circuit to increase the rate of O2 delivery

Question 11

how much of your blood does plasma take up

Answer 11

about 55%

Question 12

what does plasma do

Answer 12

transports hormones, antibodies, CO2 + other waste and nutrients
distributed the heat produced by the body

Question 13

what do platelets do

Answer 13

produce enzymes used in blood clotting

Question 14

plasma is…

Answer 14

the fluid part of the blood

Question 15

what shape is the red blood cell

Answer 15

biconcave

Question 16

rbcs are…

Answer 16

small and flexible

Question 17

rbcs have no …

Answer 17

nucleus

Question 18

rbcs contain …

Answer 18

haemoglobin

Question 19

white blood cell contains …

Answer 19

large nuclei

Question 20

what do lymphocytes do

Answer 20

produce antibodies

Question 21

what do phagocytes do

Answer 21

ingest and destroy invading microorganisms (phagocytosis)

Question 22

how is oxygen carried in our blood

Answer 22

binds to the red pigment (haemoglobin) in our rbcs
this is a weak and reversible binding to form oxyhaemoglobin

Question 23

how is CO2 carried un our blood

Answer 23

dissolves in plasma to form carbonic acid
also binds to haemoglobin

Question 24

what do arteries do

Answer 24

carry blood away from heart to the organs
when blood passes through them they stretch and can then return to the same shape
have thick walls containing muscle and elastic fibres

Question 25

what is lumen

Answer 25

hollow space inside a blood vessel

Question 26

what do veins do

Answer 26

carry blood away from the organs to the heart

Question 27

what is the difference between arteries and veins

Answer 27

veins have valves veins have thinner walls than arteries

Question 28

what are capillaries

Answer 28

tiny vessels that form a huge network linking arteries and veins

Question 29

what is the use of capillaries thin walls

Answer 29

enables substances to diffuse easily out of your blood and into your cells and vice versa

Question 30

what are the 2 types of fat

Answer 30

saturated and unsaturated

Question 31

what are the 2 ways the body carries cholestrol

Answer 31

low density lipoprotein and high density lipoprotein