Exchange and Transportation

Question 1

Features of specialised exchange surfaces

Answer 1

Large surface area
surfaces are very thin
Surfaces are permeable
Good supply of blood (internal medium)
Good supply of External medium

Question 2

What is alveoli ?

Answer 2

Small sack like things that are found in the lungs at the very end
Their job is to exchange oxygen and carbon dioxide between the air and the blood

Question 3

Veins

Answer 3

They take oxygen from the body to the heart

Question 4

Arteries

Answer 4

Arteries transport blood away from the heart to the organs. They all carry oxygenated (contains oxygen) blood (apart from the pulmonary artery)

Artery walls have thick layers of muscle. This makes them strong and able to cope with the high pressure at which blood is pumped out by the heart.
The walls have elastic fibres, allowing them to stretch and spring back.

Question 5

How are roots adapted

Answer 5

Roots are adapted for taking up both water and minerals from the soil around them.

Question 6

How is alveoli a specialiled exchange surface?

Answer 6

The alveoli (small air sacs in the lungs) are adapted for exchanging carbon dioxide and oxygen between the blood and air.
Alveoli create a very large surface area in the lungs to allow maximum diffusion of oxygen into your blood, and carbon dioxide into the air.

Question 7

How are leafs a specilied exchange surface

Answer 7

Leaves are adapted for exchanging carbon dioxide and oxygen between the leaves and the surrounding air.

Question 8

Capillaries

Answer 8

Capillaries have thin walls and pass very close to the body cells.

In capillaries, waste products, such as carbon dioxide, move out of the cells and into the blood.
In capillaries, food and oxygen moves out of the blood and into the cells.

Answer 9

Blood enters the heart via the atriums
Once filled with blood, the atria contract, forcing blood down into the ventricles below.
When the ventricles contract, they force blood to exit the heart.

Answer 10

Deoxygenated blood arrives at the lungs from the heart via the pulmonary artery. The lungs oxygenate (supply oxygen to) the blood before it returns to the heart through the pulmonary vein. The pathway of oxygen into the blood is like this:
Air is breathed into the lungs through the trachea (windpipe).
The trachea divides into two tubes called the bronchi.
The bronchi divide to form bronchioles.
The bronchioles divide until they end up in tiny air sacs called alveoli.
There are millions of alveoli.
They are surrounded by a network of capillaries, allowing for oxygen and carbon dioxide to be exchanged between the blood in the capillaries and the air in the lungs.