DENDROLOGY

Detailed explanation-1: -Answer and Explanation: Small, spiny leaves help desert plants by reducing water loss through transpiration. Transpiration is evaporation of water through the openings in the leaves, called stomata. Desert plants also tend to have a waxy coating on these reduced leaves, which further prevents water loss.

Detailed explanation-2: -Drought tolerance (or drought dormancy) refers to a plant’s ability to withstand desiccation without dying. Plants in this category often shed leaves during dry periods and enter a deep dormancy. Most water loss is from transpiration through leaf surfaces, so dropping leaves conserves water in the stems.

Detailed explanation-3: -In deserts, there is scarcity of water. So, in order to adapt to water scarce areas, desert plants have their leaves reduced to spines. Spines reduce water loss by transpiration significantly by reducing the surface area of leaves. Thus, they help in conserving water.