Cells require energy to perform essential functions like movement, shape change, repair, and transport. Autotrophs can produce their own food through photosynthesis, which converts sunlight into the chemical energy of sugars. Photosynthesis occurs in plant leaves through chloroplasts and involves three stages: light energy is captured and used to make ATP and NADPH, which are then used to produce carbohydrates from carbon dioxide and water. The process is influenced by factors like light, concentration of materials, and temperature.

1. CELLS
&
EN
ER
GY
PHOTOSYNTHESIS

2. Need energy to:
•move
•change shape
•repair structure
•make new cell parts
•transport food
•expel wastes

3. Sun is ultimate source of energy
Autotrophs – make own food
Heterotrophs – eat other orgs
Energy is obtained through Biochemical
Pathways
= linked chemical reactions
(product of one is reactant of
another)

4. Photosynthesis- Light energy converted to
chemical energy of organic compounds (carbs)
Autotrophs only
Cellular Respiration- Organic compounds
broken down to create ATP
Autotrophs & Heterotrophs

5. 6CO2 + 6H20 + solar energy C6H12O6 + 6O2
• Occurs in leaves where chloroplasts are abundant

6. •White light made of visible spectrum (different wavelengths)

7. • Plants contain pigments (compounds that absorb light)
• Chlorophyll – reflects green light (green leaves); uses
red & blue
• Carotenoids – reflect yellow, orange, brown (fruits/flowers)

8. 3 STAGES
1. Energy captured from
light
2. Energy used to make
ATP & NADPH (high
energy compound)
3. ATP & NADPH used to
make carbs from O2

9. • Light
• Concentration
• Temperature

10. • Light
• Concentration
• Temperature