Topic 3.8 Review Book
Photosynthesis
Name: ___________________
Topic 3 The Chemistry of Life
Topic 3.8: Photosynthesis (Textbook pages 82-90)
Key facts
1. Photosynthesis involves the conversion of light energy into chemical energy and it usually
involves chloroplasts. (Some prokaryotic cells are capable of carrying out photosynthesis.)
2. Sunlight is used in photosynthesis as the initial source of energy. Sunlight is composed of a
range of wavelengths (colors).
3. Chlorophyll is the main pigment involved in the absorption of sunlight so that photosynthesis
may occur.
4. Wavelengths of light that are not absorbed by plant pigments are reflected. There are
accessory pigments that help chlorophyll in the absorption of different wavelengths of
sunlight.
5. Red and blue wavelengths of light are absorbed by chlorophyll and contribute greatly to the
process of photosynthesis.
6. Green wavelengths of light are not absorbed (they are reflected) and they do not contribute
to the process of photosynthesis.
7. Light energy is used to produce ATP, and to split water molecules to form oxygen and
hydrogen.
8. The oxygen is produced by photolysis (splitting of water) and is given off by plants into the
environment.
9. The hydrogen and ATP produced by photosynthesis are used to fix carbon dioxide to make
organic molecules, mainly glucose.
10. Photosynthesis occurs in two stages, light dependent and light independent.
11. The light dependent phase requires light, while the light independent phase requires the
products of the light dependent phase.
12. The light dependent reactions produce ATP, hydrogen and oxygen (which is given off into
the atmosphere).
13. The light independent reactions fix carbon dioxide to produce organic molecules such as
glucose.
14. The rate of photosynthesis can be determined by measuring the production of oxygen or by
measuring the uptake of carbon dioxide. The rate can also be determined by measuring the
biomass increase of a plant.
15. Temperature increases the rate of photosynthesis, up until denaturation occurs.
16. Higher carbon dioxide levels will also increase the rate of photosynthesis up to a certain
level.
17. Light intensity also has an effect on photosynthesis rate.
Complete the following.
1. What energy conversion occurs in photosynthesis?
2. Explain the composition of sunlight.
3. What is the main photosynthetic pigment that absorbs light?___________________
Topic 3.8 Review Book
Photosynthesis
Name: ___________________
4. What color of light is not able to be absorbed by green plants?_________________
5. What colors of light are absorbed most by green plants?_______________________
6. What happens in photolysis?
7. What is the waste gas given off by photosynthesis?_________________
8. What is carbon fixation?
9. What atmospheric gas is essential for photosynthesis to occur?_________________
10. Name three ways one could measure the rate of photosynthesis.
11. Besides hydrogen from the photolysis of water, what other energy source is essential for
carbon fixation?___________
12. Produce a graph showing the effect of temperature on the rate of photosynthesis. Annotate
where denaturation would occur.
Topic 3.8 Review Book
Photosynthesis
Name: ___________________
13. Produce a graph showing the effect of increasing light intensity on the rate of
photosynthesis.
14. Produce a graph showing the effect of increasing carbon dioxide concentration on the rate
of photosynthesis.
15. Photosynthesis is said to have two stages, what are they?
16. Write the general equation for photosynthesis.
17. Write the general equation for cell respiration.
18. Explain the products of the light dependent stage of photosynthesis.
19. Explain the product of the light independent stage of photosynthesis.