How are cactus adapted to survive in a desert?

Cactus plants have developed several special adaptations that help them survive in the harsh desert environment where water is scarce and temperatures are extreme:

1. Thick, Fleshy Stem – The stem of a cactus is green and swollen to store large amounts of water. It also performs photosynthesis instead of leaves.
2. Spines Instead of Leaves – Cacti do not have broad leaves. Instead, they have sharp spines which reduce water loss by minimizing surface area and also protect the plant from animals.
3. Waxy Coating – A thick, waxy layer covers the stem, preventing water from evaporating in the hot desert sun.
4. Shallow but Wide Root System – Cactus roots spread out near the surface to quickly absorb even small amounts of rainwater. Some also have deep taproots to access underground water.
5. CAM Photosynthesis – Cacti use a special type of photosynthesis (Crassulacean Acid Metabolism) in which stomata open at night instead of daytime, reducing water loss.

In short, cacti are perfectly adapted to desert life by storing water, reducing water loss, and protecting themselves from heat and predators.