Bio 111 Study Guide
Chapter 10 – Photosynthesis
BEFORE CLASS:
Reading:
 Read the whole chapter from p. 185-207. You can skip the topic of cyclic electron flow on p. 196-197.
 Figure 10.18 puts all of the light reactions together for you. Study it and understand it well! Figure
10.22 displays a great overview of photosynthesis.
 Figure 10.23 is an incredible figure that shows how concepts from chapters 5-10 would be at work
together in a living plant cell.
Definitions:
photosynthesis –
chloroplast –
stomata –
stroma –
thylakoids –
grana –
chlorophyll –
NADP+ –
photophosphorylation –
carbon fixation –
electromagnetic spectrum –
visible light –
absorption spectrum –
chlorophyll a –
chlorophyll b –
action spectrum –
carotenoids –
photosystem –
reaction-center complex –
light-harvesting complex –
primary electron acceptor –
photosystem II (PSII) –
photosystem I (PSI) –
G3P (glyceraldehyde 3-phosphate) –
RuBP (ribulose bisphosphate) –
rubisco (RuBP carboxylase oxygenase) –
C3 plants –
photorespiration –
C4 plants –
PEP carboxylase –
CAM plants –
Questions/Problems:
1. Label the following parts and molecules in the diagram below: chloroplast, thylakoids, stroma, light, H2O,
CO2, O2, sugar, NADP+, ADP, Pi, ATP, NADPH, Light Reactions, and Calvin cycle.
DURING CLASS:
Significance of Photosynthesis
Plant Structures
Leaf:
Chlorophyll:
Characteristics of Light
Electromagnetic spectrum –
Pigment Molecules –
Absorption spectrum –
Action spectrum–
Photosynthesis
Purpose –
Summary equation –
Two Stages:
Photosystems:
Redox Reactions:
Coenzymes:
Light Reactions
Purpose –
Steps:
Mechanism of ATP Synthesis:
Photophosphorylation –
Chemiosmosis –
Calvin Cycle
Purpose –
Steps:
Review of Photosynthesis
Animation – Photosynthesis
Adaptations to Photorespiration
Photorespiration –
C4 plants:
CAM plants:
**Take Away Concept**
Photosynthesis provides the foundation for both energy and nutrients that support almost all living
organisms in the world.
AFTER CLASS:
Questions/Problems:
1. What color(s) of light drive photosynthesis in green plants most efficiently? What color of light is least
effective in driving photosynthesis? Explain how you know both answers.
2. Which of the following statements describes the results of photosynthesis?
6CO2 + 6H2O + light energy → C6H12O6 + 6O2
a. CO2 is reduced and H2O is oxidized.
b. C6H12O6 is oxidized and O2 is reduced.
c. O2 is oxidized and H2O is reduced.
d. CO2 is oxidized and C6H12O6 is reduced
e. O2 is reduced and CO2 is oxidized.
3. Use the following words to label the figure that depicts the basics of the Light Reactions below:
ATP, chlorophyll, ETC, small ETC, H+, H2O, NADP+, NADP+ reductase, NADPH, O2, photosystem I, photosystem II,
and primary electron acceptor (some are used more than once). Also draw in where light energy plays a role
and where the electrons get excited and are passed along.
Location:
4. This figure of the Light Reactions is a more complete picture. Use the following words to label the figure
below: ADP, ATP, ATP synthase, chlorophyll, ETC, small ETC, H+, H2O, NADP+, NADP+ reductase, NADPH, O2,
photosystem I, photosystem II, Pi, and primary electron acceptor (some are used more than once). Draw in
where light energy plays a role and where the electrons get excited and are passed along. Also draw the many
H+ ions involved in the chemiosmosis part of photophosphorylation. Label the parts of the chloroplast shown
(stroma, thylakoid, and thylakoid space), and indicate in the gray box on the right where the ATP and NADPH
are headed next.
5. To depict the Calvin Cycle, draw a circle below with an arrow going in the top and one coming out the
bottom. Then add and label the molecules ADP, ATP, CO2, G3P, H+, NADP+, NADPH, Pi, RuBP, and rubisco.
Then label the three main steps of the Calvin Cycle: Carbon Fixation, Reduction, and Regeneration.
Location:
6. The Calvin Cycle requires ATP and NADPH, products of the light reactions. If a classmate asserted that the
light reactions don’t depend on the Calvin cycle and, with continual light, could just keep on producing ATP
and NADPH, how would you respond?
7. Why are C4 plants able to photosynthesize with no apparent photorespiration?
8. Why is a CAM plant better adapted to a very dry climate than a C 3 plant?