1. Biology 1308, Chapter 8, Photosynthesis Photosynthesis converts solar energy into chemical energy. Organisms that carry on photosynthesis are called autotrophs. Heterotrophs are organisms that feed on other organisms. Autotrophs and heterotrophs use organic molecules produced by photosynthesis Pigments allow photosynthetic organisms to capture solar energy.

2. Biology 1308, Chapter 8, Photosynthesis Flowering Plants as Photosynthesizers Photosynthesis occurs in the green parts of plants Leaves contain mesophyll tissue specialized for photosynthesis Water is taken up by roots and transported to leaves by veins Carbon dioxide enters through openings in the leaves called stomata Light energy is absorbed by chlorophyll and other pigments in thylakoids of chloroplasts

3. Biology 1308, Chapter 8, Photosynthesis

4. Photosynthetic Reaction Solar energy + 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 Glucose and oxygen are the products of photosynthesis The oxygen given off comes from water CO 2 gains hydrogen atoms and becomes a carbohydrate (Glucose)

5. Biology 1308, Chapter 8, Photosynthesis Photosynthesis consists of two sets of reactions Photo refers to capturing light Synthesis refers to producing a carbohydrate

6. Biology 1308, Chapter 8, Photosynthesis Light Reactions Photosynthesis takes place in chloroplasts. Light reactions consist of two alternate electron pathways: Noncyclic electron pathway Cyclic electron pathway Both pathways transform solar energy to chemical energy Both pathways produce ATP (Energy) The noncyclic pathway also produces NADPH (Reducing power – to make Carbohydrate from Carbon dioxide)

7. Biology 1308, Chapter 8, Photosynthesis Photosynthesis Versus Cellular Respiration Both plant and animal cells carry out cell respiration Only plant cells photosynthesize Both processes utilize an electron transport chain and chemiosmosis for ATP production Photosynthesis reduces CO 2 to carbohydrates and releases O 2 Respiration utilizes O 2 and gives off CO 2

8. Biology 1308, Chapter 8, Photosynthesis Photosynthesis and Respiration Compared