Chloroplast

Definition

Chloroplasts are organelles found in plant cells and some protists that conduct photosynthesis. They convert light energy into chemical energy stored in glucose.

5 Must Know Facts For Your Next Test

1. Chloroplasts contain chlorophyll, the pigment that captures light energy.
2. They have a double membrane structure with an intermembrane space.
3. The thylakoid membranes inside chloroplasts are where the light-dependent reactions occur.
4. The stroma, the fluid-filled space around the thylakoids, is where the Calvin cycle takes place.
5. Chloroplasts have their own DNA, which is similar to bacterial DNA.

Review Questions

• What role do chloroplasts play in photosynthesis?
• Where in the chloroplast do the light-dependent reactions occur?
• What is found within the stroma of a chloroplast?

Related terms

Photosynthesis: The process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water.

Thylakoid: A membrane-bound compartment inside chloroplasts where the light-dependent reactions of photosynthesis take place.

Chlorophyll: The green pigment located within the thylakoid membranes that absorbs light energy for photosynthesis.