Explain in detail about Crassulacean Acid Metabolism.

Explanation

Crassulacean Acid Metabolism or CAM cycle:
It is one of the carbon pathways identified in succulent plants growing in semi - arid or xerophytic condition . This was first observed in crassulaceae family plants like Bryophyllum, Sedum , Kalanchoe and is the reason behind the name of this cycle . It is also noticed in plants from other families . Examples : Agave , Pountia , Pineapple and Orchids. The stomata are closed during day are open during night (Scotoactive ) . This reverse stomatal rhythm helps to conserve water loss through transpiration and will stop the fixation of `CO_(2)` during the day time . At night time CAM plants fix `CO_(2)` with the help of Phospho Enol Pyruvic acid (PEP) and produce oxalo acetic acid(OAA). Subsequently OAA is converted into malic acid like `C_(4)` cycle and gets accumulated in vacuole increasing the acidity . During the day time stomata are closed and malic acid is decarboxylated into pyruvic acid resulting in the decrase of acidity . `CO_(2) ` thus formed enters into Calvin Cycle and produces carbohydrates .
Significance of CAM plants fix `CO_(2)` with the helps of Phospho ENol Pyruvic acid (PEP) and produce oxalo acetic acid (OAA). Subsequently OAA is converted into malic acid like `C_(4)` cycle and gets accumulated in vavuole increaseing the acidity . During the day time stomata are closed and malic acid is decarboxylated into pyruvic acid resulting in the decrease of acidity `CO_(2)` thus formed enters into Calvin Cycle and produce carbohydrates . Significance of CAM Cycle .
1. It is advantageous for succulent plants to obtain `CO_(2)` from malic acid when stomata are closed .
2 . During day time stomata are closed and `CO_(2)` is not taken but continue their photosynthesis .
3. Stomata are closed during the day time and help the plants to avoid transpiration and water loss,.