1. Inside A Chloroplast

2. Structure of the Chloroplast
Double membraned organelle
Outer membrane is smooth
Inner membrane forms stacks of connected sacs called thylakoids
Thylakoid stack is called the granum (grana-plural)
Gel-like material around grana called stroma

3. Function of the Stroma Light Independent reactions occur here
ATP used to make carbohydrates like glucose
Location of the Calvin Cycle

5. Thylakoid membranes Light Dependent reactions occur here
Photosystems are made up of clusters of chlorophyll molecules
Photosystems are embedded in the thylakoid membranes
The two photosystems are:
Photosystem I
Photosystem II

6. Photosynthesis Overview

7. Energy Carriers NADP+ = Reduced Form
Nicotinamide Adenine Dinucleotide Phosphate (NADP+)
NADP+ = Reduced Form
Picks Up 2 high-energy electrons and H+ from the Light Reaction to form NADPH
NADPH carries energy to be passed on to another molecule

8. Light Dependent Reactions
Occurs across the thylakoid membranes
Uses light energy
Produce Oxygen from water
Convert ADP to ATP
Also convert NADP+ into the energy carrier NADPH

9. Light Dependent Reaction

10. Light Dependent Reaction

11. Photosystem I Discovered First
Active in the final stage of the Light Dependent Reaction
Made of 300 molecules of Chlorophyll
Almost completely chlorophyll a

12. Photosystem II Discovered Second
Active in the beginning stage of the Light Dependent Reaction
Contains about equal amounts of chlorophyll a and chlorophyll b

13. Photosynthesis Begins
Photosystem II absorbs light energy
Electrons are energized and passed to the Electron Transport Chain
Lost electrons are replaced from the splitting of water into 2H+, free electrons, and Oxygen
2H+ pumped across thylakoid membrane

14. Photosystem I
High-energy electrons are moved to Photosystem I through the Electron Transport Chain
Energy is used to transport H+ from stroma to inner thylakoid membrane
NADP+ converted to NADPH when it picks up 2 electrons & H+

15. Phosphorylation Enzymes in thylakoid membrane are called ATP Synthase
As H+ ions passed through thylakoid membrane, enzyme binds them to ADP
Forms ATP for cellular

17. Light Reaction Summary
Reactants:
H2O
Light Energy
Energy Products:
ATP
NADPH

18. Light Independent Reaction
ATP & NADPH from light reactions used as energy
Atmospheric C02 is used to make sugars like glucose and fructose
Six-carbon Sugars made during the Calvin Cycle
Occurs in the stroma

19. The Calvin Cycle

20. The Calvin Cycle
Two turns of the Calvin Cycle are required to make one molecule of glucose
3-CO2 molecules enter the cycle to form several intermediate compounds
A 3-carbon molecule called Ribulose Biphosphate (RuBP) is used to regenerate the Calvin cycle