2.1 - Photosynthesis

Question 1

In what organisms is photosynthesis carried out?

Answer 1

Green plants and algae

Question 2

How does a plant get the light energy it needs to carry out photosynthesis?

Answer 2

The chlorophyll in the chloroplasts absorb the Sun’s light energy

Question 3

What is the word equation for photosynthesis?

Answer 3

Carbon dioxide + water (+ light energy) –> glucose + oxygen

Question 4

What energy transfer allows photosynthesis to happen?

Answer 4

Light energy is transferred to chemical energy

Question 5

How does the plant gain the carbon dioxide and water for photosynthesis?

Answer 5

The carbon dioxide is taken in by the leaves, and water is taken in by the roots

Question 6

What is the light energy in photosynthesis used to do?

Answer 6

Convert the carbon dioxide and water into glucose and oxygen

Question 7

What is the by-product of photosynthesis?

Answer 7

Oxygen

Question 8

How can we show whether photosynthesis has happened in a leaf?

Answer 8

Through the iodine test for starch (because some glucose is converted into starch). The iodine solution will turn blue-black when starch is present.

Question 9

What are variegated leaves? What happens when we use the iodine test on them?

Answer 9

Leaves that have patches of green (with chlorophyll) and patches of white (without chlorophyll). Only the green patches turn iodine solution blue-black to show that starch has been made.