How does leaf anatomy differ in CAM plants?

Leaf anatomy in CAM plants is different as they have large vacuoles for storing malic acid and thick cuticles to reduce water loss.

In more detail, Crassulacean Acid Metabolism (CAM) plants have a unique leaf anatomy that allows them to survive in arid conditions. The most distinctive feature of CAM plants is their large vacuoles. These vacuoles are used to store malic acid, a compound that is produced during the night when the stomata are open and carbon dioxide is absorbed. This malic acid is then broken down during the day to release carbon dioxide for photosynthesis while the stomata are closed to prevent water loss.

Another key feature of CAM plant leaf anatomy is the presence of a thick cuticle. The cuticle is a waxy layer that covers the surface of the leaves and stems. This layer is particularly thick in CAM plants, acting as a barrier to water loss. This is crucial for these plants as they often live in environments where water is scarce, such as deserts.

Furthermore, CAM plants often have a reduced number of stomata, the tiny pores on the leaf surface through which gas exchange occurs. This is another adaptation to reduce water loss. When the stomata are closed during the day, water loss through transpiration is minimised.

Lastly, the mesophyll cells in CAM plants, where photosynthesis takes place, are packed with chloroplasts. These chloroplasts contain the enzyme Rubisco, which is crucial for the fixation of carbon dioxide during photosynthesis. This high concentration of chloroplasts ensures that the plant can maximise photosynthesis during the day when the stored carbon dioxide is released from the malic acid.

In summary, the leaf anatomy of CAM plants is specifically adapted to their environment, with large vacuoles for storing malic acid, a thick cuticle and reduced stomata to minimise water loss, and densely packed chloroplasts for efficient photosynthesis.