Question

Which of the following is capable of performing photosynthesis at high temperature i.e. at $50^{o}$ C?
A. Opuntia
B. Mango
C. Potato
D. None of the above

Answer 1

Xerophytic plants (also known as succulents) are the plants which are adapted to survive in the hot climate. These plants have special modifications which help them to survive in the hot temperature. These plants usually grow in hot and humid climates and can easily perform photosynthesis at high temperatures.

Complete step by step answer: According to their habitats the plants can be classified as hydrophytes, mesophytes, xerophytes and halophytes.
Hydrophytes are the plants which grow in the aquatic habitat (eg: Water lily).
Mesophytes are the plants that grow in moderate moisture and temperature (eg: Mango and potato).
Xerophytes are the plants that grow in dry conditions (eg: Opuntia).
Halophytes are the plants that grow in saline conditions (eg: Portulaca).
The structure and the chemical process of the xerophytic plants are adapted to conserve and store large amounts of water. The plants which have such physiological and morphological adaptations are known as xeromorphic plants.
The leaves of the opuntia plant are modified into spines to reduce the water loss by transpiration and therefore the leaves do not perform the process of photosynthesis. The stems on the other hand are modified to have a green, flat, spongy and leaf-like structures (known as phylloclades) which are modified to perform the photosynthesis. The stems contain chlorophyll and also store the food for the plant.
Opuntia is the plant capable of performing photosynthesis at high temperature. So, the correct answer is option (A).

Note: Opuntia is commonly known as prickly pear and belongs to the cactus family. It is a xerophytic plant majorly found in dry sunny areas. These are small low-growing shrubs which survive in areas of low rainfall and are tolerant to drought.
Some of the other examples of xerophytic plants include Century plant (Agave americana), Desert date (Balanites aegyptiaca), Gum arabic (Vachellia nilotica), Jujube (Ziziphus jujuba), Rubber bush (Calotropis procera), cacti, pineapple and some gymnosperm plants.