LS1 Science- Diffusion & Osmosis

Question 1

‘Diffusion’

Answer 1

‘Diffusion’ is the net movement of particles from a region where they are of higher concentration to a region where they are of lower concentration, that is , down a concentration gradient
-Diffusion may occur with or without a membrane

Question 2

Diffusion (Concentration gradient)

Answer 2

The concentration gradient is a difference in concentration between two regions

Question 3

Concentration gradient in relation to diffusion

Answer 3

Particles in fluids possess kinetic energy.

• Particles diffuse down their concentration gradient
• The higher the concentration gradient, the higher the rate of diffusion

Question 4

Semi-permeable membrane

Answer 4

Only allows certain substances to pass through (Mostly water)

Question 5

When does diffusion stop?

Answer 5

When there is no concentration gradient= (dynamic equilibrium)
-The concentration of particles is equal

Question 6

Osmosis

Answer 6

It is the net movement of water molecules from a solution of higher water potential to a solution of lower water potential, THROUGH A PARTIALLY-PERMEABLE MEMBRANE

NOTE: Osmosis occurs only when a selectively permeable membrane is used!

Question 7

Water potential (gradient)

Answer 7

It is the measure of the tendency of water to move from one place to another
(When a partially permeable membrane separates two solutions of different water potentials,)a water potential gradient is created
a
-A dilute solution has a higher water potential, vice versa

Question 8

Difference between osmosis and diffusion

Answer 8

(Diffusion; Osmosis)

Types of gradients:
(Concentration gradient; water potential gradient)

(difference in concentration between two regions; measure the tendency of water to move from one place to another)