Here the question is stating about the hot deserts.
Hot deserts are characterized by extremely hot and arid climate.
Average annual range of rainfall is as low as 25 cm.
Deserts lack vegetation except at some patches.
Plants that survive in hot deserts have several adaptation to check the loss of water through transpiration.
These adaptation include, succulent stems, cuticularized epidermis, Reduction of leaves into spines or thorns, stems modified into phylloclades and deep roots to absorb water.
DNA replication needs to occur because existing cells divide to produce new cells. Each cell needs a full instruction manual to operate properly. So the DNA needs to be copied before cell division so that each new cell receives a full set of instructions!
