Blood

Question 1

what 4 main parts make up blood

Answer 1

plasma, red blood cells, white blood cells and platelets

Question 2

what is blood plasma and what are its functions

Answer 2

The liquid part of the blood
- it carries blood through the vessels
- transports many dissolved substances such as CO2 and glucose

Question 3

that percentage of the blood is plasma

Answer 3

55%

Question 4

what are platelets and what is their purpose

Answer 4

they are fragments of larger cells. they have no nucleus, their function is to cause blood clots if a blood vessel becomes damaged

Question 5

what are some of the adaptations of red blood cells

Answer 5

contain haemoglobin
biconcave shape
no nucleus

Question 6

what are the 3 types of blood vessels

Answer 6

arteries, veins, capillaries

Question 7

in what direction do veins carry the blood

Answer 7

towards the heart

Question 8

in what direction do arteries carry the blood

Answer 8

away from the heart

Question 9

what are some adaptations of veins and their reasons

Answer 9

have thin walls as they carry low-pressure blood
have valves - to stop blood flowing backwards

Question 10

what are some adaptations of capillaries

Answer 10

very small - high SA: V ratio
very thin walls - maximise diffusion

Question 11

what are some adaptations of arteries

Answer 11

narrow and have thick walls - allowing them to carry high pressure blood