Chapter 10 - Photosynthesis

Photosynthesis

1. Occurs in plants, algae, some protists, and some prokaryotes

2. A REDOX reaction where CO₂ is reduced into glucose (C₆H₁₂O₆) and water (H₂O) is oxidized into Oxygen (O₂)

3. 6 CO₂ + 12 H₂O + Light Energy → C₆H₁₂O₆ + 6 O₂ + 6 H₂O

Autotrophs

1. Producers

2. Do not need to eat other organisms

Heterotrophs

1. Consumers

2. Get energy from eating other organisms

Chloroplasts

1. Site of photosynthesis

2. In all green parts of a plant, but mostly the leaves

Thylakoids

1. Inside the stroma

2. Stacks of thylakoids are called grana

3. Chlorophyll is found in the thylakoids

Chlorophyll

1. Green pigment of leaves, absorbs light for photosynthesis

Light Reaction

1. Depend on sunlight to happen

2. Water is broken down to produce O₂, NADPH, and ATP

Dark Reactions (Calvin Cycle)

1. Does not require light (Uses the ATP from light reactions as fuel)

2. Uses the NADPH and CO₂ to produce glucose (Carbon Fixation)

3. Takes 3 turns to produce G3P and then 3 more to finish the glucose (6)

4. Anabolic

Electromagnetic Spectrum

1. Entire range of radiation

2. 380-750 nm is visible light

Photosynthetic Pigments

1. Substances that absorb visible light

Absorption Spectrum

1. Graph showing a pigment’s light absorption versus the wavelength of the light

Action Spectrum

1. Shows relative effectiveness of different light wavelengths at powering photosynthesis

Chlorophyll A

1. Main pigment for photosynthesis

2. Violet-blue and red light

Chlorophyll B

1. Accessory pigment to expand light absorption

2. Red and blue

Carotenoids

1. Accessory pigments used for protection from light that would damage chlorophyll

2. Antioxidants