2(d) Movement of Substances

Question 1

Diffusion

Answer 1

The passive movement of molecules from an area of higher concentration to an area of lower concentration

Question 2

Factors affecting diffusion

Answer 2

Temperature
* Molecules have more kinetic energy at high temperatures so they diffuse faster.
Concentration Gradient
* The greater the difference in concentrations, the faster diffusion will occur.
Surface Area to Volume ration
* The larger the SA:VOL the faster the diffusion will occur
Distance
* The longer the distance, the slower diffusion will be.

Question 3

Osmosis

Answer 3

The movement of water from an area of higher water potential to an area of lower water potential acrosss a selectively-permeable membrane.

Question 4

Turgid

Answer 4

When a cell or tissue is swollen from water uptake/holding too much water.

Question 5

Flaccid

Answer 5

When a cell becomes soft due to the loss of water.

Question 6

Active Transport

Answer 6

The movement of molecules form low to high concentration requiring energy in the form of ATP.

Question 7

Investigate diffusion and osmosis using living and non-living systems

Pratical