Chapter 4

Question 1

What is blood complied of?

Answer 1

Blood is complied of:
55% Plasma
Less than 1% White blood cells and platelets
45% red blood cells

Question 2

What is the function of plasma?

Answer 2

Waste Carbon dioxide is carried to the lungs in it.
Urea formed in the liver from the breakdown of excess proteins is carried to your kidneys where it is removed from blood.
Small soluble products of digestion pass into the plasma from your small intestine

Question 3

What are the functions/ features of red blood cells?

Answer 3

Red blood cells pick up oxygen from air in your lungs and carries it to where it is need?
They are biconcave discs - increases surface area
They are packed with red pigment called haemoglobin that binds to oxygen
No nucleus to make space for haemoglobin.

Question 4

What do white blood cells do?

Answer 4

White blood cells are much bigger than red bloods
Form part of the body’s defence against harmful microbes.
Some form antitoxins against poisons made by microorganisms
Some engulf and digest invading bacteria and viruses

Question 5

What do platelets do?

Answer 5

Small fragments of cells

Important in helping the site of a wound to clot

Question 6

What are the characteristics of artistes?

Answer 6

• Thick walls
• Carries blood away from the heart
• small lumen
• thick layer of muscle and elastic fibres.

Question 7

What are the characteristics of veins?

Answer 7

They carry blood towards the heart and away from the organs.

• Relatively thin walls
• large lumen
• often have valves to stop the back flow of blood

Question 8

What are the characteristics of capillaries?

Answer 8

Form a huge network of tiny vessels linking the arteries and veins

• tiny vessels with narrow lumen
• walls a single cell thick to enable substances to defuse through them

Question 9

What is double circulation?

Answer 9

One transport system carries blood from your your heart to your lungs and back again. This enables oxygen and carbon dioxide to be exchanged in air in the lungs.
The other transport system carries blood from your heart to all other organs of your body.

Question 10

Why is a double circulatory system need?

Answer 10

It makes our circulatory system very efficient. Fully oxygenated blood returns to the heart from the lungs lungs. This blood can be sent off at a high pressure.

Question 11

How is blood pumped in the heart?

Answer 11

The vena cava brings deoxygenated blood into the right atrium this flows to the right ventricle the atria contract squeezing the ventricle forcing deoxygenated blood to the lungs via the pulmonary artery. Pulmonary vain brings oxygenated blood back from the lungs. This enters in to the left atrium this then enters the left ventricle where the atria contract and push the oxygenated blood around the body via the aorta.

Question 12

What is a stint?

Answer 12

A stint is a metal Cage inserted with ballon to help with coronary heart disease. This ballot is inflates pushing the mesh cage to the side forcing fatty deposits aside. This opens up the artery.

Question 13

What is a natural pacemaker?

Answer 13

A natural pace is made of valves from pigs or cattle or even a human donor, These work extremely well however only last 12-15 years.

Question 14

What is an artificial pacemaker and valves?

Answer 14

Patients have to take anti clot medication for the rest of their lives to stop blood clotting around there artificial valve.
Whereas an artificial pacemaker use electrical pulses to stimulate the beat properly.

Question 15

What does the gas exchange system achieve?

Answer 15

The gas exchange system supplies oxygen and removes waste carbon dioxide.

Question 16

How does the diaphragms movements co inside with breathing in and out?

Answer 16

When you breath in the diaphragm flattens lowering the pressure due to due to a larger area of the internals of the lungs. When you breathe out the diaphragm raise reducing the area creating a higher pressure forcing air out.

Question 17

What is the structure of alveoli?

Answer 17

Each alveolus is surrounded by a thin wall of cells to allow a small gap between blood and air for diffusion. The circle are in the middle is where blood is moved in and out of.
The thin wall of cells allows oxygen to diffuse in and carbon dioxide to diffuse out. A good blood supply maintains the concentration gradient allowing diffusion to take place.

Question 18

What does Epidermal tissue in plants do?

Answer 18

They cover the surface to protect them, they often create a waxy substance that waterproofs the surface.

Question 19

What does palisade mesophyll do?

Answer 19

They contain lots of chloroplasts for photosynthesis

They are tightly packed to achieve this.

Question 20

What does spongy mesophyll do?

Answer 20

Spongy mesophyll contains some chloroplasts.

But has a large air spaces and large surface area to make the diffusion of gasses easier.

Question 21

What is the function of stomata?

Answer 21

To enable gasses to flow in and out.

Question 22

What does phloem transport?

Answer 22

Phloem transports the sugars made by photosynthesis to the rest of the plant.

Question 23

What does Xylem Transport?

Answer 23

Xylem transport water and mineral ions. Xylem tissue is around the outside of the plant. This is made up of mostly dead cells.