Question

Which one is not an oviparous animal?
a. Human
b. Crow
c. Hen
d. Crocodile

Answer 1

Hint: Generally, animals are classified into oviparous and viviparous animals based on the mode of reproduction. Oviparous animals that lay eggs and Viviparous animals are those that directly give birth to the young ones without laying eggs.

Complete answer:
Oviparous animals are the animals that lay eggs with or without embryonic development within the mother. This is the reproductive method of most of the amphibians, reptiles, fishes, birds, insects, and the monotremes.

Most animals living on the land lay eggs which are protected by hard shells. They fertilize their eggs internally. Other oviparous organisms lay the unfertilized eggs. After laying that, the male organism lays sperm on the top layer of the eggs to fertilize it. This is called external fertilization.

Oviparous is an evolutionary strategy for reproduction. One or many eggs can be laid by the oviparous animals. Each egg is a gamete, which is the female genetic material. In many species, male supply sperm in the form of gamete, which finds its way to the female genetic material. After fertilization, the eggs are subdivided into an embryo. Many oviparous animals lay small fragile eggs, others lay a large, strong egg.

The only downside of oviparous is that the oviparous animals must protect their eggs from predators during their complete development.
Hence, (A) is the correct answer.

Additional information:
Viviparous animals are those which give birth to their young ones, unlike oviparous animals. For instance, dog, cow, crocodile, deer, horse, lion, tiger, human, etc.., The egg cells are developed in the womb of the female organism, they give birth to the younger ones.

Note: Monotremes are the special order of mammals that act like oviparous animals. Unlike other mammals, they laid eggs instead of giving birth to young ones. Typical examples of monotremes include platypus and echidna. After birth, they fed the young ones with the milk secreted in their glands.