Photosynthesis Study Guide Name _____________________ Period _____
Stage 1: Capturing Light Energy
1. A photon is a tiny packet of light ______________.
2. True or False All photons carry the same amount of energy.
3. Briefly explain why plants appear green. __________________________________________
4. True or False A particular type of pigment can absorb a photon of any energy level.
5. The major light absorbing pigment in plants is _________________ which is found inside
the organelle called the __________________.
6. True or False Plant and animals cells contain chloroplasts.
7. What happens when atoms in a pigment absorb light energy? _________________________
8. Many reactions in photosynthesis are classified as ________________ - _________________
reactions. These reactions involve the transfer of electrons from one molecule to another.
10. True or False In cells, electrons travel alone.
11. In cells, electrons travel from one molecule to another attached to a ________________.
12. As review, what is the electrical charge on a proton? _______________
As review, what is the electrical charge on an electron? ______________
As review, what do oppositely charged particles do to each other? ______________________
13. A proton and an electron together make up a _______________ atom.
Stage 2: Using Light Energy to Make ATP and NADPH
14. Look at Figures in your notebook. Identify the location of a chlorophyll
15. True or False A thylakoid is a disk-like structure.
16. What happens to electrons in chlorophyll when photons of light strike the chloroplasts? _____
17. Each excited electron, traveling as part of a ________________ atom, leaves the chlorophyll
and jumps to a nearby protein in the thylakoid membrane.
18. What does the proton pump do to the hydrogen that is carrying an “excited” electron? ______
19. What is the role of the energy that is released by the proton pump? _____________________
20. What molecule is produced when the protons diffuse back through a channel protein? ______
21. Review - Study the following steps of photosynthesis to determine the order in which they take
place. Write the number of each step in the blank provided.
____ a. An electron that is attached to a proton becomes excited by the light.
____ b. Protons inside the thylakoid are driven out through a protein channel.
1 c. Photons strike the chloroplasts.
____ d. The excited electron, with its attached proton, moves to a thylakoid membrane, where
it powers the pumping of the proton across the membrane.
____ e. The force of the protons leaving the thylakoid adds a phosphate to ADP, forming
22. The second type of chlorophyll releases an excited electron that combines with a hydrogen
atom that is then attached to NADP. What molecule is formed from the hydrogen and
23. What are the ATP and NADPH used for? ________________________________________
Stage 3: Building Carbohydrates
24. What is the ultimate goal of photosynthesis? _______________________________________
25. The process of capturing carbon atoms and using them to build glucose and other compounds
is called the ____________ cycle.
26. Is photosynthesis a more complicated process than you thought it was? _______
27. In the space below, write the chemical equation for the overall process of photosynthesis.
28. What are the reactants of photosynthesis? _____________________________________
29. What are the products of photosynthesis? _____________________________________
30. How do plants store the sugars produced as a result of photosynthesis? __________________
31. What can plants do with the stored starch molecules? ________________________________
32. Multiple Choice - Circle the correct answer.
The ultimate goal of photosynthesis is to
A. make ATP from carbon dioxide.
B. construct carbon containing molecules that serve as an energy source.
C. convert ADP to ATP by using energy from the sun.
D. use enzymes to speed up chemical reactions.