Movement into and out of cells

Question 1

What is diffusion?

Answer 1

Diffusion is the movement of particles from a high concentration to a low concentration.

Does NOT require energy.

Question 2

What is osmosis?

Answer 2

Osmosis is the movement of water from a high concentration of water (low solutes) to a low concentration of water (high solutes) across a semi permeable membrane.

Does NOT require energy.

Question 3

What is active transport?

Answer 3

The movement of particles from a low concentration to a high concentration.

This DOES require energy.

Question 4

What affects the rate of diffusion?

Answer 4

surface area:volume ratio
distance of diffusion
the concentration gradient
temperature

Question 5

Practicals on diffusion

Answer 5

Potato- change concentration of the sucrose solution when potatoes were placed in. Measure the %change in mass.

agar jelly- different size cubes and measure time taken for the colour of the water to change completely.