1. Question… Where do you get all of your energy to survive?
Photosynthesis – using light energy, carbon dioxide, and water to make food for the plant. (glucose)
How does the plant do this?
What parts of the plants help this process?
How does the plant absorb light?

2. Energy In A Cell
Chapter 9

3. The Need for Energy (Ch. 9, Sec. 1)
All organisms need ENERGY
Plants (autotrophs) obtain energy from the sun
Other organisms (heterotrophs) eat plants to get the plant’s stored energy

4. ATP
Adenosine Triphosphate = 1 adenosine molecule, 1 ribose molecule, + 3 phosphate groups
Energy is stored in the bonds between the phosphates
When the bond breaks, energy is released
Phosphate can be reattached to ‘recharge’ the ATP molecule

5. Photosynthesis
Ch. 9, Sec. 2

6. Photosynthesis = plants use sunlight energy, carbon dioxide and water to make simple sugars (glucose)
6CO2 + 6H2O  C6H12O6 + 6O2
Occurs in 2 phases
Light-dependent Reactions
Light-independent Reactions

7. Chloroplasts & Pigments
Chloroplasts: where photosynthesis takes place (contains pigment: chlorophyll)

8. Pigments = compounds that absorb light
Most common: chlorophyll, carotenoids
Visible Light made up of a range of colors
ROY G BIV
Colors that don’t get absorbed, are reflected, and are what you see

9. Thylakoid Membranes contain pigments
Chlorophyll pigment that gives plants their green color
Carotenoids pigments in plants that become visible when plants stop producing chlorophyll

10. Light-Dependent Reactions
1st phase of Photosynthesis, requires light energy
Energy gets captured by electrons
The energized electron splits a water molecule causing Oxygen to be released and ATP to be generated

12. Light-Independent Reactions
Calvin Cycle = 2nd part of photosynthesis, does not require light
Uses CO2 and H to form sugars
Takes place in the chloroplast
Generation of the sugars requires ATP produced during the Light-Dependent Reactions

14. End result…
1 molecule of glucose (C6H12O6) and 6 molecules of oxygen (O2) waste.

15. Practice What are the inputs for photosynthesis?
What are the outputs for photosynthesis?
Is a product considered an input or output? Explain.