Diffusion-PAPER 1

Question 1

What is diffusion?

Answer 1

Diffusion is the process by which particles of a substance spread out from each other, moving from a region where they are in high concentration to a region of low concentration.

Question 2

Diffusion goes from a ??? concentration to a ????? concentration.

Answer 2

From HIGH to LOW

Question 3

The particles will move down the conc gradient until?

Answer 3

They are all evenly spread

Question 4

In order to do this, particles of a substance must be…

Answer 4

Free to move.

Question 5

Diffusion allows substances to pass into or out of cells across the cell membrane - but they must be???

Answer 5

DISSOLVED

Question 6

What do the substances diffuse through?

Answer 6

A cell membrane

Question 7

What are all cell mebranes?

Answer 7

SEMI PERMEABLE.

Question 8

Give an example of diffusion in humans.

Answer 8

Gas exchange in the lungs, oxygen is moved from a high (inhaled air) to low conc (blood circulating lungs).

Question 9

What factors affect the rate of diffusion?

Answer 9

the difference in concentrations (concentration gradient)
• the temperature
• the surface area of the membrane.