Diffusion

Question 1

What is diffusion

Answer 1

Movement of particles from area of high concentration to an area of lower concentration
It happens in solutions and gases because particles can move about randomly

Question 2

What affects speed of diffusion

Answer 2

Temperature - hotter equals faster diffusion
Concentration gradient - the steeper the difference in concentration the faster the diffusion
Distance of diffusion- shorter the distance the faster the gradient
Surface area - the larger the surface area the faster the diffusion as more particles can pass through at once

Question 3

What substances diffuse in and out of cells?

Answer 3

Dissolved substances
Nutrients - e.g. Glucose, amino acids and water.
Oxygen
Carbon dioxide

These small molecules Diffuse through partially permeable membrane

Question 4

How are diffusion gradients maintained?

Answer 4

Blood remove oxygen and bring carbon dioxide to the lungs

Breathing replenishes oxygen and removes carbon dioxide