Part 2- Osmosis

Question 1

What is diffusion?

Answer 1

The movement of particles on a liquid or gas. They move from an area of high concentration to an area of lower concentration. The rate of diffusion is effected by temperature, the concentration gradient and the available surface.

Question 2

What is osmosis?

Answer 2

The diffusion of water through partially permeable membrane.

Question 3

What is active transport?

Answer 3

The process by which dissolved molecules move across a cell membrane from a lower to higher concentration. In active transport, particles move against the concentration gradient- and therefore require an input of energy from a cell.

Question 4

Uses of active transport-

Answer 4

To uptake minerals such as magnesium ions into the root hair cell against the concentration gradient in the soil.

Question 5

Active transport allows-

Answer 5

Glucose molecules to move into blood in small intestine against convection gradient. (i.e lower to higher)

Question 6

How do animals and plants absorb substances?

Answer 6

Using diffusion.

Question 7

Why do animals and plants need a large surface area?

Answer 7

So that they can exchange a large amount of, for example, oxygen, carbon dioxide, water, etc.

Question 8

What must exchange surfaces be?

Answer 8

Thin and have a large surface area.