Question

Which parts/belongings of animals are particularly susceptible to temperature changes?
(A) Eggs and Larvae.
(B) Eggs and Feathers.
(C) Eggs and Hair.
(D) Eggs and Skin.

Answer 1

Hint : We know that all birds are egg-laying, egg-laying mammals are Echidna and Platypus, reptiles, amphibians, fishes. Viviparous animals are the ones that give birth to their off-springs directly. Embryonic development takes place inside the female body, and this feature is called viviparity. Viviparity comes from a Latin word viviparous in which vivus means living, and pario means give birth to. In viviparous animals, both fertilization and embryonic development are internal.

Complete Step By Step Answer:
Fertilization in the animal kingdom is classified as external and internal fertilization. External fertilization is a process in which the fusion of sperm and egg takes place outside the female body. Embryo development, in the case of external fertilization, takes place in an external environment. Internal fertilization is a process in which the fusion of sperm and egg takes place inside the female body, while the embryo development may take place outside or inside the environment. Based on embryo development in internally fertilized animals, they are classified into oviparous and viviparous animals. Oviparous animals don't give birth to their off-springs directly. The development of an embryo takes place outside the female body. That is internal or external fertilization but external embryonic development in these animals. All egg-laying animals/mammals are oviparous animals, and this feature is called oviparity. The yolk present provides all nutrients to the off-springs in an egg.
Eggshells are made up of calcium carbonate. Some animal's eggs are fragile (Reptiles), and some develop hard shells. Temperature variations affect the life cycles of animals. Every animal has a fixed period of reproduction, some reproduce during summers while some during winter. Since, only eggs and larvae form the components of the reproductive cycle.
Therefore, the correct answer is option A.

Note :
Remember that the young ones take nutrients directly from the mother but not the yolk. If the zygote develops in oviducts, then it is known as histotrophic viviparity. If the nutrients are provided by the placenta, then it is known as hemotrophic, viviparity. Placental viviparity is the advanced embryo development of animals. It is seen in humans. Embryonic development takes place in the uterus; all nutrients required for the embryo are provided through the umbilical cord.