Campbell+Biology+Concepts+and+Connections+9th+Ed

Photosynthesis

The process by which green plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose, using carbon dioxide and water.

Photoautotrophs

Organisms that use light energy to produce their own food, such as plants and certain bacteria.

Chloroplast

An organelle in plant cells where photosynthesis takes place, containing chlorophyll and other pigments.

Light Reactions

The first stage of photosynthesis, occurring in the thylakoid membranes, where solar energy is converted to chemical energy in the form of ATP and NADPH.

Calvin Cycle

The second stage of photosynthesis that takes place in the stroma, during which ATP and NADPH are used to synthesize glucose from carbon dioxide.

Rubisco

An enzyme that catalyzes the first step of the Calvin Cycle, fixing carbon dioxide into organic compounds.

Stroma

The thick fluid inside chloroplasts where the Calvin Cycle takes place.

Thylakoids

Membranous sacs in chloroplasts where the light reactions of photosynthesis occur.

ATP synthase

An enzyme that synthesizes ATP from ADP and inorganic phosphate, powered by a proton gradient.

Photophosphorylation

The process of generating ATP from ADP and inorganic phosphate during the light reactions of photosynthesis.

Carbon fixation

The process of converting carbon dioxide into organic compounds in the Calvin Cycle.

C3 plants

Plants that fix carbon directly through the Calvin Cycle and are most commonly affected by photorespiration in hot, dry conditions.

C4 plants

Plants that fix carbon dioxide into a four-carbon compound to minimize photorespiration and optimize photosynthesis in hot, dry climates.

CAM plants

Plants that open their stomata at night to fix carbon dioxide, thereby conserving water during the day.

Urushiol

The allergenic compound found in poison ivy sap that causes allergic reactions and skin irritation.

Global warming

The long-term increase in Earth’s average temperature due to rising levels of carbon dioxide and other greenhouse gases.

NADPH

A carrier molecule that donates high-energy electrons for reducing carbon compounds in the Calvin Cycle.

Electron transport chain

A series of proteins in the thylakoid membrane that transfer electrons during the light reactions, leading to ATP and NADPH production.

Photorespiration

A process that occurs when rubisco adds oxygen instead of carbon dioxide to RuBP, resulting in a wasteful pathway that decreases photosynthetic efficiency.