Photosynthesis Study Guide
ACT Course Standards are written in italics.
E-2b: Explain the functions of chloroplast.
1. Describe the function of the chloroplast. Organelle in which photosynthesis takes place. ________________
_______________________________________________________________________________________
_______________________________________________________________________________________
2. Where is the chloroplast located? plant cell ____________________________________________________
3. Chloroplasts contain saclike photosynthetic membranes called thylakoids_______________.
4. What is the grana? Stacks of thylakoids
5. The region outside the thylakoid membranes in the chloroplasts is called the stroma
6. Label the chloroplast below. Include: thylakoid, stroma, grana, lumen (inner thylakoid)
7. Where does the light dependent reaction take place? (Label on diagram above)thylakoid ________________
8. Where does the light-independent reaction take place? (Label on diagram above) stroma _______________
E-2c: Explain the interaction between pigments, absorption of light, and reflection of light.
1. What is the main pigment involved in photosynthesis? chlorophyll __________________________________
2. List 2 accessory pigments in plants. Carotenoids, anthocyanins _____________________________________
3. Why do we see green in plants? Chlorophyll absorbs all colors except for green, which is reflected. _______
_______________________________________________________________________________________
4. Where is chlorophyll located in the plant cell? Be specific! In the photosystems within the
chloroplast
5. What role does chlorophyll play in photosynthesis? Absorbs solar energy (sunlight) ____________________
6. If a plant has purple leaves, does it still undergo photosynthesis? Explain. Yes, the plant still has
chlorophyll, which is required for photosynthesis, but the purple pigments mask the chlorophyll.
E-2d: Describe the light dependent and light independent reactions of photosynthesis.
1. What occurs in the process of photosynthesis? _Plants use solar energy to convert carbon dioxide
and water into high energy sugars (glucose) and oxygen.
2. Write the overall equation for photosynthesis using words. Plants use solar energy to convert carbon
dioxide and water into high energy sugars (glucose) and oxygen.
3. Write the overall equation for photosynthesis using chemical formulas.
CO2 + H2O + sunlight  C6H12O6 + O2
4. What does photosynthesis require in addition to water and carbon dioxide? ___sunlight______ ___________
_______________________________________________________________________ ____________________
5. What are the 2 stages of photosynthesis called? Light-dependent reactions and light-independent
reactions ___________________________________________________________________________________
6. Label the following diagram. Describe what happens during each step of the light dependent reaction.
7. What is used during the light dependent reaction? Water (H2O) and sunlight ___________________________
8. What is produced during the light dependent reaction? Oxygen (O2), NADPH, and ATP ____________________
9. How does oxygen leave the plant? Through the stomata ____________________________________________
10. Circle the letter of each sentence that is true about the light dependent reactions. Correct the false
statements.
a. They convert ADP into ATP
b. They produce oxygen gas
c. They convert oxygen into carbon dioxide (They convert water into oxygen.)
d. They convert NADP+ into NADPH
e. High energy electrons move through the electron transport chain from photosystem II to
photosystem I.
f.
Photosynthesis begins when pigments in photosystem I absorb light. (photosystem II)
g. The difference in charges across the thylakoid membrane (more Hydrogen ions inside the
thylakoid than outside) provides the energy to make ATP.
11. The light energy from the sun is converted into chemical energy and stored in the NADPH and ATP.
12. What happens to CO2 in the Calvin cycle (light-independent reaction)? It is converted into glucose ________
_______________________________________________________________________________________
13. CO2 goes into the Calvin cycle from the atmosphere. It enters the plant through the stomata.
14. ATP and NADPH provide energy for the Calvin cycle. This energy comes from the ______light
dependent reactions_.
15. Circle the statement that is true about the Calvin cycle. Correct the false statements.
a. The main products of the Calvin cycle are six carbon dioxide molecules. (reactants)
b. Carbon dioxide molecules enter the Calvin cycle from the atmosphere.
c. Energy from ATP and high-energy electrons from NADPH are used to convert 3carbon molecules into similar 3-carbon molecules.
d. The Calvin cycle uses six molecules of carbon dioxide to produce a single 6-carbon
sugar molecule.
16. What are the products of the Calvin cycle? C6H12O6 (glucose), ADP, NADPH
17. Label the diagram below. Be able to describe what happens at each phase.
E-2e: Relate the products of the light-dependent reactions to the products of the light-independent
reactions.
1. Complete the illustration of the overview of photosynthesis by writing the products and reactants of
the process, as well as the energy source that excites electrons.
CO2
O2
sunlight
ADP
NADP+
Light dep.
reactions
Light indep.
reactions
ATP
NADPH
Cellulose
2 3-C Mol
C6H12O6
starch
H2O
2. Relate the products of the light-dependent reactions to the products of the light-independent
reactions. ATP and NADPH are produced during the light-dependent reactions. These products are
used in the Calvin Cycle (light independent reactions) to produce glucose. (They provide energy to
fuel the reactions.) The resulting ADP and NADP+ then go back to the thylakoid to accept more
energy in the light dependent reactions.
3. Complete the Venn Diagram.



Thylakoid
Uses H2O, sunlight
Produces O2, ATP,
NADPH
Share
products.
(ATP,
NADPH,
ADP,
NADP+)
Occurs in
plant cells



Stroma
Uses ATP, NADPH,
CO2
Produces glucose,
ADP, NADPH
Light Dependent Reactions
Light Independent Reactions
4. What are 3 factors that affect the rate of photosynthesis?
Temperature, carbon dioxide, water, sunlight
5. Is the following statement true or false? Increasing the intensity of light decreases the rate of
photosynthesis. False
Section 8-1
Autotrophs and Heterotrophs
1. Where does the energy of food originally come from? The sun
2. Complete the table describing the types of organisms.
Type
Description
Examples
Autotrophs
Organisms that make their own
food.
Organisms that obtain energy
from the food they eat.
Plants (apple tree, daisy)
Heterotrophs
Animals (lion, human)
Chemical Energy and ATP
3. What is one of the principle chemical compounds that cells use to store energy? ATP
4. How is ATP different from ADP? ATP has 3 phosphate groups and ADP only has two phosphate groups.
5. Label each part of the ATP molecule illustrated below.
Adenine
Ribose
Phosphate groups
ATP
6. When a cell has energy available, how can it store small amounts of that energy? In can add a
phosphate group to ADP, producing ATP.