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Section 8-1: Energy and Life
Plants and some other types of organisms are able to use light energy from the sun to produce food.
The characteristics of ATP make it an exceptionally useful molecule that is used by all types of cells as their basic energy source.
Section 8-2: Photosynthesis: An Overview
The experiments performed by van Helmont, Priestley, Ingenhousz, and other scientists reveal that in the presence of light, plants transform carbon dioxide and water into carbohydrates and release oxygen as a byproduct.
Photosynthesis uses the energy of sunlight to convert water and carbon dioxide into oxygen and high-energy sugars.
In addition to water and carbon dioxide, photosynthesis requires light and chlorophyll, a molecule found in chloroplasts.
Section 8-3: The Reactions of Photosynthesis
The process of photosynthesis includes the light-dependent reactions as well as the Calvin cycle.
The light-dependent reactions produce oxygen gas and convert ADP and NADP+ into ATP and NADPH. The light-dependent reactions occur in different areas of the thylakoid, called photosystem I and photosystem II.
The Calvin cycle uses ATP and NADPH from the light-dependent reactions to produce high-energy sugars. The Calvin cycle is also known as the light-independent reactions.