1. Photosynthesis
Chapter 3.1

2. Capturing the Energy of Life
All organisms require energy
Autotrophs obtain energy directly from the sun and store it as glucose during a process called photosynthesis
6CO2 + 6H2O    6O2 + C6H12O6
sunlight

3. Energy for Life Processes
Autotrophs (producers) convert sunlight, CO2, and H2O into glucose (their food)
Plants, algae, blue-green bacteria
Heterotrophs obtain necessary carbon by eating autotrophs
Animals, fungi, protists

5. Biochemical Pathways Photosynthesis is a biochemical pathways
Series of reactions where the product of one reaction is the reactant of the next

6. Light Absorption in Chloroplasts
Chloroplasts absorb light energy from the sun during the light dependent reactions
Chloroplasts = inner membrane is folded into disc-shaped sacs called thylakoids
Thylakoids = contain chlorophyll and are in stacks called granum
Granum = surrounded by a gel-like material called stroma

7. Chloroplast

8. Pigments When all colors are absorbed, the object appears black
When all colors are reflected, the object appears white
If only one color is reflected (green), the object appears that color (ex: Chlorophyll)

9. Photosystems Photosynthesis involves many steps Two Photosystems:
Light dependent
Light independent (Calvin Cycle)

10. Light Dependent Water is split, giving off oxygen
H2O   O2 
Water is split, giving off oxygen
Light is absorbed by chlorophyll
“Excites" electrons and makes ATP (energy)
Takes place in the thylakoids

11. Light Independent (Calvin Cycle)
CO2  C6H12O6
Carbon dioxide is split, providing carbon to make glucose
The ultimate product is glucose.
Depends on products from the light reactions
Takes place in the stroma

12. Transportation of Nutrients
Xylem
Moves water from the roots up the stem to the leaves
Phloem
Moves glucose from the leaves down the stem to the roots