Question

In succulents like cacti, stomata close during the day. Why?

Answer 1

Succulents:

1. Succulents are plants having thickened, fleshy, and a swollen leaf or stem sections, which help to retain water in arid and dry climates or soil conditions.
2. Some examples of succulents are Cactus, Agave, Aloe vera, Euphorbia, etc.

Stomata:

1. Stomata are cell structures found in the epidermis of plant leaves that help them to exchange carbon dioxide and water with the atmosphere.
2. Succulents have a scotoactive type of stomata.
3. Stomata that open at night because of organic acid metabolism and close during the day are known as scotoactive stomata.

Why do stomata close during the day in succulents?

1. The stomata of succulents remain closed during the day but open during the night.
2. Cactus (succulent) has evolved an adaptation to high heat and drought conditions by closing their stomates throughout the day to prevent moisture loss.
3. Because of the CAM metabolism, the cactus can open its stomata at night to uptake the carbon dioxide, completing the entire gas exchange before the sun comes up.