Question

What is diapause and its significance?

Answer 1

Hint: Diapause is a mechanism where animals are surviving in a minimal condition such as drought, high rise in temperature and reduced food availability. It is one condition which animals adapt to survive in any unfavorable conditions. Amphibians are the animals which live in land as well as water. Their excretion mode is similar to mammals.

Complete answer:
Amphibians and mammals excrete urea hence, they were ureotelic animals. They adapted such a process to conserve water, as ammonia is highly toxic. Animals which maintain diapause consistently are arthropods and some insects.
The period where unfavorable conditions are hard to tackle there animals have special abilities to maintain Osmoregulation. Diapause is also a stage of suspended development where animals do not undergo full development, rather partial development is being carried forward as the circumstances or habitat is not good.
Amphibians which secrete urea are- toads, frogs and some fishes. The activity level of animals during that time is quite low or immobile. Significance of diapause are- zooplanktons in lakes and ponds undergo suspended development in order to protect their life from drastic and unpleasant conditions. Diapause adapting animals shows hibernation and aestivation also. Hibernation is also similar to diapause where an organism undergoes hibernation to protect itself from extreme climatic conditions.

Note:
Insects undergo diapause because usually it triggered their life cycle by environmental cues like- changes in daylight, temperature and food availability. Temperature and other environmental effects are not permanent but when they occur it becomes difficult to control. Examples of insects undergoing diapause are silk moths, Bombyx mori.