HORTICULTURE

Detailed explanation-1: -Spines are also modified leaves. In cacti, spines are wholly transformed leaves that protect the plant from herbivores, radiate heat from the stem during the day, and collect and drip condensed water vapour during the cooler night.

Detailed explanation-2: -Those prickly spines that are so characteristic of the cactus family are actually modified leaves!

Detailed explanation-3: -Most species of cacti have lost true leaves, having only spines, which are highly modified leaves, as well as defending against herbivores. Spines help prevent water loss by reducing airflow close to the cactus. In the absence of leaves, enlarged stems carry out photosynthesis.

Detailed explanation-4: -Instead of leaves, most cacti have spines or scales (which are modified leaves). These spines and scales do not lose water through evaporation (unlike regular leaves, which lose a lot of water). The spines protect the cactus from predators (animals that would like to eat the cactus to obtain food and/or water).

Detailed explanation-5: -Leaf spines are adaptations of xerophytic plants like cactus and mexican poppy. The leaves of these plants get converted into spines. The conversion into spines reduces the surface area.