8.1 Overview of Photosynthesis

1. 8.1 Overview of 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. 8.1 Overview of 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. Leaves and Photosynthesis

4. 8.1 Overview of Photosynthesis • Photosynthetic Reaction • Solar energy + 6CO2 + 6H2O  C6H12O6 + 6O2 • Glucose and oxygen are the products of photosynthesis • The oxygen given off comes from water • CO2 gains hydrogen atoms and becomes a carbohydrate

5. 8.1 Overview of Photosynthesis • Photosynthesis consists of two sets of reactions • Photo refers to capturing light • Synthesis refers to producing a carbohydrate • The two sets of reactions are called the: • Light Reactions • Calvin Cycle Reactions

6. 8.5 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 CO2 to carbohydrates and releases O2 • Respiration utilizes O2 and gives off CO2

7. Photosynthesis and Respiration Compared