AQA GCSE Biology Osmosis

Question 1

What is the dependent variable in this investigation?

Answer 1

Chip mass

Question 2

What is the independent variable in this investigation?

Answer 2

Concentration of sugar solution

Question 3

State two control variables in this investigation

Answer 3

. Temperature
. Time

Question 4

State two hazards and precautions

Answer 4

. You can get cut by the sharp knife
. Use a cutting board

. Solution can spill
. Clean up spills immediately

Question 5

Explain why the potato pieces in 0.4 mol/dm3 solution decreased in mass

Answer 5

The salt solution is slightly less concentrated than the potato cells.

Water moves into the potato cells by osmosis.

The potato pieces gain water and increase in mass.

Question 6

Explain why the potato pieces at 0.6 mol/dm3 solution decreased in mass

Answer 6

The salt solution is more concentrated than the potato cells.

Water moves out of the potato cells by osmosis.

The potato pieces lose water and decrease in mass.

Question 7

Explain why the potato pieces at 1.0 mol/dm3 solution decreased in mass

Answer 7

The salt solution is much more concentrated than the potato cells.

Water moves out of the potato cells by osmosis.

The potato pieces lose water and decrease in mass.

Question 8

Explain why the potato pieces at 0.4 mol/dm3 and at 0.6 mol/dm3 solution increased in mass

Answer 8

The salt concentration is higher than inside the potato cells.

Water moves out of the potato cells by osmosis.

The potato pieces lose water and decrease in mass.

Question 9

Explain why the potato pieces at 1.0 mol/dm3 solution increased in mass

Answer 9

The salt concentration is much higher than inside the potato cells.

Water moves out of the potato cells by osmosis.

The potato pieces lose water and decrease in mass.

Question 10

State two ways this investigation can be improved

Answer 10

. Extend the range of salt concentrations
. Ensure the temperature stays consistent throughout the investigation