| Light reaction | Dark reaction |
| 1. It occurs in the grana of the chloroplast. | 1. It occurs in the stroma of the chloroplast. |
| 2. It occurs only in the presence of light. | 2. It occurs in the presence or absence of light. |
| 3. It occurs in the grana of the chloroplast. | 3. It occurs in the stroma of the chloroplast. |
| 4. Light reaction absorbs oxygen and light energy | 4. Dark reaction absorbs only CO2. |
| 5. End products are O2, ATP and NADPH. | 5. End product is Glucose. |
| 6. Photolysis of water occurs. | 6. Carbon fixation occurs. |
| 7. First stage of photosynthesis. | 7. Second stage o: photosynthesis. |
