B.4 organisation in us

Question 1

what does plasma transport

Answer 1

to transport substances around the body via blood
eg
-nutrients, oxygen and amino acids
-waste products, carbon dioxide +urea
-hormones, antibodies

Question 2

what make up the human circulatory system

Answer 2

-blood
-blood vessels
-heart

Question 3

state what red blood cells contain

Answer 3

-haemoglobin that binds to oxygen to transport it from the lungs to tissues

Question 4

how do white blood cells help the body

Answer 4

-prevent it from infection

Question 5

state what platelets do

Answer 5

-cell fragments that start clotting process at wound sites

Question 6

what actually makes blood red

Answer 6

haemoglobin

Question 7

what are platelets

Answer 7

Cell fragments that start the clotting process at wounds.

Question 8

What are the capillaries there for?

Answer 8

Substances diffuse in and out of the blood

Question 9

What kind of circulatory system do humans have?

Answer 9

A double circulatory system

Question 10

What do stents do?

Answer 10

Keep narrowed or blocked arteries open.

Question 11

What do statins do?

Answer 11

Reduce cholesterol levels reducing the risk of coronary heart disease.

Question 12

the heart has ..

Question 13

how can damaged heart valves be replaced

Answer 13

-biological valves
-mechanical valves

Question 14

What is the resting heart rate controlled by?

Answer 14

A group of cells in the right atrium form a natural pacemaker.

Question 15

What are artificial pacemakers used for?

Answer 15

They’re used to correct irregularities in the heart rhythm.

Question 16

What are artificial hearts used for?

Answer 16

Keep patients alive while they wait for a transplant or to allow their own heart to rest.

Question 17

what are the lungs protected by

Answer 17

ribcage

Question 18

What do the alveoli do?

Answer 18

Provide a large surface area and a rich supply of blood capillaries, so gas can diffuse efficiently.

Question 19

state how arteries are adapted to their function

Answer 19

-thick walls
-contain layers of muscle to make them strong
-elastic fibres to allow them to stretch and spring back

Question 20

how are capillaries adapted to its function

Answer 20

-permeable walls so substances can diffuse in and out
-walls are only 1cell thick, increasing rate of diffusion

Question 21

how are veins adapted to their function

Answer 21

-bigger lumen than arteries to help blood flow despite the lower pressure

Question 22

how are red blood cells adapted

Answer 22

-biconcave disc (gives a large surface area for absorbing oxygen)
-no nucleus, more room to carry oxygen

Question 23

how are white blood cells adapted

Answer 23

contain a nucleus (to defend the body against infection and disease)