Short note on: Crassulacean Acid Metabolism.

1.	Short note on: Crassulacean Acid Metabolism.
Answer» Crassulacean Acid Metabolism (CAM). 1. It is one more alternative pathway of carbon fixation found in desert plants. 2. It was first reported in the family Crassulaceae, therefore called as CAM (Crassulacean Acid Metabolism). 3. In CAM plants, stomata are scotoactive i.e. active during night, hence initial CO₂ fixation occurs in night. 4. Thus, C₄ pathway fix CO₂ at night and reduce CO₂ in day time via the C₃ pathway by using NADPH formed during the day. 5. PEP caboxylase and Rubisco are present in the mesophyll cell (no Kranz anatomy). 6. Formation of malic acid during dark is called acidification (phase I). 7. Malate is stored in vacuoles during the night. 8. Malate releases CO₂ during the day for C₃ pathway within the same cell is called deacidification (phase II). 9. Examples of CAM plants: Kalanchoe, Opuntia, Aloe etc. 10. The Chemical reactions of the carbon dioxide fixation and its assimilation are similar to that of C₄ plants.

Answer»

Crassulacean Acid Metabolism (CAM).

1. It is one more alternative pathway of carbon fixation found in desert plants.

2. It was first reported in the family Crassulaceae, therefore called as CAM (Crassulacean Acid Metabolism).

3. In CAM plants, stomata are scotoactive i.e. active during night, hence initial CO₂ fixation occurs in night.

4. Thus, C₄ pathway fix CO₂ at night and reduce CO₂ in day time via the C₃ pathway by using NADPH formed during the day.

5. PEP caboxylase and Rubisco are present in the mesophyll cell (no Kranz anatomy).

6. Formation of malic acid during dark is called acidification (phase I).

7. Malate is stored in vacuoles during the night.

8. Malate releases CO₂ during the day for C₃ pathway within the same cell is called deacidification (phase II).

9. Examples of CAM plants: Kalanchoe, Opuntia, Aloe etc.

10. The Chemical reactions of the carbon dioxide fixation and its assimilation are similar to that of C₄ plants.

Discussion