SAFOLO — 2d — Movement of molecules

Question 1

Diffusion?

Answer 1

Diffusion is the movement of particles of a gas or liquid from an area of high to low concentration

Question 2

Osmosis?

Answer 2

The movement of water through a semi-permeable membrane from an area of high water potential (diluted) to an area of low water potential (concentrated)

Question 3

Active transport?

Answer 3

A process that requires energy to move molecules across a cell membrane from an area of low concentration to high concentration

Question 4

Limiting factors of movement in and out of cells?

Answer 4

• Surface area to volume ratio
• Temperature
• Concentration gradient
• Distance

Question 5

How does surface area to volume ratio affect movement in and out of cells?

Answer 5

As SA:V increases, rate of movement increases. This is because there is a larger surface area in which substances can move through.
Big (whale/human): small SA:V ratio
Small (mouse): big SA:V ratio

Question 6

How does temperature affect movement in and out of cells?

Answer 6

As temp. increases, rate of movement increases. This is because particles gain more kinetic energy and will move faster.

Question 7

How does concentration gradient affect movement in and out of cells?

Answer 7

As conc. gradient increases, rate of movement increases. This is because a stronger conc. gradient is present.

Question 8

How does distance affect movement in and out of cells?

Answer 8

The greater the distance, the slower the movement since the particles have to travel far.