| A | B |
|---|
| ADP | A molecule whose energy has been used and is waiting for more. |
| ATP | A very common molecule that cells use for immediate energy. |
| Autotroph | Organisms that make their own food. |
| Heterotroph | Organisms that have to get food by eating other organisms. |
| Photosynthesis | The process by which the energy from the Sun is used to convert water and carbon dioxide into sugar and oxygen. |
| Chlorophyll | The main light-absorbing pigment in plants. |
| Thylakoids | Stacked, saclike membranes that contain clusters of chlorophyll; the site of the light-dependent reactions |
| Stroma | The liquid-filled region inside the chloroplast that the thylakoids float in. |
