CCEA Biology - Photosynthesis & Plants

Question 1

Investigating the Need for Light in Photosynthesis: Procedure

(8 marks)

Answer 1

Destarch plant.

Cover part of leaf with lightproof paper/foil.

Make drawing of the leaf.

Place plant in bright light - 7 hours.

Test leaf for starch using 4-step starch test.

Make another drawing of the leaf - showing areas of the leaf that tested positive and those that tested negative for starch.

Question 2

Investigating the Need for Light in Photosynthesis: Results

3 marks

Answer 2

Only the areas that have been exposed to light will photosynthesise

Therefore test positive for starch

Showing that light is necessary for photosynthesis.

Question 3

How long should you place the plant next to a bright light when Investigating the Need For Light in Photosynthesis?

(1 mark)

Answer 3

7 hours

Question 4

What should you cover the plant with when Investigating the Need For Light in Photosynthesis?

(1 mark)

Answer 4

Lightproof Paper/Foil.

Question 5

Is Light necessary for Photosynthesis?

1 mark

Answer 5

Yes.