Movement in and out of cells

Question 1

Definition of diffusion?

Answer 1

Movement of molecules from an area of high concentration to an area of low concentration.

Question 2

Definition of osmosis?

Answer 2

Movement of water molecules from a dilute solution to a concentration solution through a partially permeable membrane.

Question 3

Definition of active transport?

Answer 3

Movement of molecules from a local concentration to a higher concentration using membrane bound carries and energy in the form of ATP

Question 4

What can the movements of substances in and out of shells be done by?

Answer 4

• diffusion
• active transport

Question 5

What are the four factors that affect the movement of substances?

Answer 5

1. Surface area to volume ratio.
2. Distance.
3. Temperature.
4. Concentration gradient.

Question 6

How does surface area to volume ratio affect the movement of substances?

Answer 6

The rate of diffusion, osmosis and active transport is higher in cells with a large surface area to volume ratio.

Question 7

How does distance affect the movement of substances?

Answer 7

If substances only have a short distance to move, then they will move in and out of cells faster.

Question 8

How does temperature affect the movement of substances?

Answer 8

As the particles in a substance get warmer, they have more energy so they move faster.

Question 9

Diffusion in living systems :

Answer 9

Particles flow through the cell membrane where there’s a higher concentration to where there’s a lower concentration