1. Chapter 4.2
Overview of
Photosyntheis

2. and the increasing complexity of systems.
SB3. Students will derive the relationship between single-celled and multi-celled organisms
and the increasing complexity of systems.
a. Explain the cycling of energy through the processes of photosynthesis and respiration.
b. Compare how structures and function vary between the six kingdoms (archaebacteria,
eubacteria, protists, fungi, plants, and animals).
c. Examine the evolutionary basis of modern classification systems.
d. Compare and contrast viruses with living organisms.

3. KEY CONCEPT The overall process of photosynthesis produces sugars that store chemical energy.

11. Photosynthetic organisms are producers.
Producers make their own source of chemical energy.
Plants use photosynthesis and are producers.
Photosynthesis captures energy from sunlight to make sugars.

13. ENERGY ULTIMATELY COMES FROM THE SUN AND THEN BECOMES PART OF OUR FOOD

14. Chlorophyll is a molecule that absorbs light energy.

15. In plants, chlorophyll is found in organelles called chloroplasts.
leaf cell
leaf

16. Chloroplasts

18. Photosynthesis in plants occurs in chloroplasts.
Photosynthesis takes place in two parts of chloroplasts.
grana (thylakoids)
stroma

20. Two phases of the photosynthesis reaction
Light Dependent
Capture energy from the sunlight!
Phase 2
Light Independent
This captured energy is used to make sugars!

21. The light-dependent reactions capture energy from sunlight.
take place in thylakoids
water and sunlight are needed
chlorophyll absorbs energy
energy is transferred along thylakoid membrane then to light-independent reactions
oxygen is released

23. Light Dependent Reactions.
Look How Complex This Process Is!

24. The light-independent reactions make sugars.
take place in stroma
needs carbon dioxide from atmosphere
use energy to build a sugar in a cycle of chemical reactions

26. The equation for the overall process is:
6CO2 + 6H2O  C6H12O6 + 6O2
C6H12O6
granum (stack of thylakoids)
thylakoid
sunlight
1 six-carbon sugar
6H2O
6CO2
6O2
chloroplast 1 2 4 3
energy
stroma (fluid outside the thylakoids)

28. What is the equation for the chemical reaction of photosynthesis?
Six molecules of carbon dioxide react with six molecules of water to form 1 molecule of glucose and six molecules of oxygen.

29. 1 2 4 3 granum (stack of thylakoids) chloroplast sunlight 6H2O 6O2
C6H12O6
granum (stack of thylakoids)
thylakoid
sunlight
1 six-carbon sugar
6H2O
6CO2
6O2
chloroplast 1 2 4 3
energy
stroma (fluid outside the thylakoids)

31. Stage 3 is also known as the Calvin Cycle

32. The Calvin Cycle

33. Melvin Calvin at Lawrence Berkeley Laboratory