1. FOTOSINTESIS

2. Why Photosynthesis is Important?

3. THE SUN: MAIN SOURCE OF ENERGY FOR LIFE ON EARTH

6. DI MANA TEMPAT TERJADINYA FOTOSINTESIS?

7. The location and structure of chloroplasts
LEAF CROSS SECTION
MESOPHYLL CELL
LEAF
Chloroplast
Mesophyll
CHLOROPLAST
Intermembrane space
Outer
membrane
Inner membrane
Thylakoid compartment
Thylakoid
Stroma
Granum
Grana

8. Photosynthesis occurs in chloroplasts
In most plants, photosynthesis occurs primarily in the leaves, in the chloroplasts
A chloroplast contains:
stroma, a fluid
grana, stacks of thylakoids
The thylakoids contain chlorophyll
Chlorophyll is the green pigment that captures light for photosynthesis

9. WHY ARE PLANTS GREEN? Plant Cells have Green Chloroplasts
The thylakoid membrane of the chloroplast is impregnated with photosynthetic pigments (i.e., chlorophylls, carotenoids).

10. Electromagnetic Spectrum and Visible Light
Gamma rays
X-rays UV
Infrared & Microwaves
Radio waves
Visible light
Wavelength (nm)

11. KENAPA DAUN BERWARNA HIJAU?
Different wavelengths of visible light are seen by the human eye as different colors.
KENAPA DAUN BERWARNA HIJAU?
Gamma rays
X-rays UV
Infrared
Micro- waves
Radio
waves
Visible light
Wavelength (nm)

12. THE COLOR OF LIGHT SEEN IS THE COLOR NOT ABSORBED
Chloroplasts absorb light energy and convert it to chemical energy
Light
Reflected
light
Absorbed
Transmitted
Chloroplast
THE COLOR OF LIGHT SEEN IS THE COLOR NOT ABSORBED

13. Chloroplast Pigments Chloroplasts contain several pigments
Chlorophyll a
Chlorophyll b
Carotenoids

14. Chlorophyll a & b Chl a has a methyl group Chl b has a carbonyl group
Porphyrin ring
delocalized e-
Phytol tail

15. Different pigments absorb light differently

17. THERE ARE TWO PHASES IN PHOTOSYNTHESIS
THE “LIGHT REACTION”
H2o is split
2 H2O  O [H+]
NADPH and ATP are generated
THE “DARK REACTION”
NADPH and ATP from the light reaction drives CH2O productionCO2 AND [H+] :
4 [H+] + CO2  (CH2O) + H2 O
It’s really light in-dependent reaction
You have already studied it
THE “CALVIN CYCLE”

19. Cyclic Photophosphorylation
Process for ATP generation
Reaction Center => 700 nm

20. Two types of photosystems cooperate in the light reactions
Photon
ATP
mill
Photon
Water-splitting
photosystem
NADPH-producing
photosystem

21. Noncyclic Photophosphorylation
Photosystem II regains electrons by splitting water, leaving O2 gas as a by-product
Primary electron acceptor
Electron transport chain
Electron transport
Photons
PHOTOSYSTEM I
PHOTOSYSTEM II
Energy for synthesis of
by chemiosmosis

22. Plants produce O2 gas by splitting H2O
The O2 liberated by photosynthesis is made from the oxygen in water (H+ and e-)

24. The production of ATP by chemiosmosis in photosynthesis
Thylakoid compartment (high H+)
Light
Light
Thylakoid membrane
Antenna molecules
Stroma (low H+)
ELECTRON TRANSPORT CHAIN
PHOTOSYSTEM II
PHOTOSYSTEM I
ATP SYNTHASE

25. Overview of Light Reactions

26. Calvin Cycle Where does the Calvin Cycle occur? In the stroma
What goes into the Calvin Cycle?
ATP, NADPH, Carbon Dioxide
What comes out of the Calvin Cycle?
Sugar, ADP, NADP+

28. carbon fixation phase

29. each CO2 molecule is attached to a five-carbon sugar, ribulose bisphosphate (RuBP)
catalyzed by RuBP carboxylase or rubisco
six-carbon intermediate splits in half to form two molecules of 3-phosphoglycerate

30. reduction of CO2 phase

31. each 3-phosphoglycerate receives another phosphate group from ATP to form 1,3 bisphosphoglycerate.
pair of electrons from NADPH reduces,Gain, each 1,3 bisphosphoglycerate to G3P.
Electrons from NADPH change a carboxyl group to a carbonyl group.

32. regeneration of RuBP phase

33. regeneration of the CO2 acceptor (RuBP), these five G3P molecules are rearranged to form 3 RuBP molecules.
cycle must spend 3 more molecules of ATP (one per RuBP) to complete the cycle and prepare for the next.

35. Rate of Photosynthesis
What is a rate?
It is the activity per unit time.
What factors can affect the photosynthetic rate?

36. Light Intensity

37. The Effect of Light Intensity on Photosynthetic Rate

38. Temperature

39. The Effect of Temperature on Photosynthetic Rate

40. The Effect of Light Intensity and Temperature on Photosynthetic Rate
Which is the limiting factor here; light intensity or temp.?

41. Oxygen Concentration
What would a graph for increasing levels of CO2 look like?