BOTANY

Detailed explanation-1: -Xerophytes are plants which can survive in dry or desert regions, i.e. with little water. Sunken stomata ensure less water loss, thus reduces the rate of transpiration. Hence, these are characteristically found in xerophytes.

Detailed explanation-2: -Small leaves mean less evaporative surface per leaf. In addition, a small leaf in the sun doesn’t reach as high a temperature as a large leaf. Leaves and stems of many desert plants have a thick, waxy covering, keeping the plants cooler and reducing evaporative loss.

Detailed explanation-3: -To survive in drought conditions, plants need to decrease transpiration to limit their water loss. Some plants that live in dry conditions have evolved to have smaller leaves and therefore fewer stomata. Extreme examples are plants with leaves that resemble spiky thorns.

Detailed explanation-4: -Note:Sunken stomata is an adaptation used by Xerophytes to sustain in extremely harsh and dry conditions. Such stomata are present in the pits or grooves of lower epidermis thus preventing excessive water escape from the leaves of the plants.

Detailed explanation-5: -Nerium is a xerophytic plant and has sunken stomata to reduce the rate of transpiration, confined to lower epidermis.