Reproduction In Animals

Amoeba reproduces by a process known as binary fission in which parent cell divides into two equal daughter cells. Whereas in hydra reproduction occurs by budding.

Binary fission in case of amoeba

Reproduction through budding in case of hydra

In budding, the bud is formed from the parent individual whereas in binary fission no bud formation occurs. In binary fission equal division of cytoplasm takes place whereas unequal division of cytoplasm occurs in case of budding. In budding new individual is formed from old one’s whereas in fission old individual splits to give two new individuals.

External development of young ones occurs in case of frog and fish due to which its protection from the surrounding decreases. So to cope up with the loss they lay more no. of eggs because not many have a chance to survive. Whereas in case of cow and human beings development occurs inside the mother’s body and the egg is protected. So they give birth to only one at a time.

Yes, some animals can produce offspring even without formation of zygotes. For example, in case of amoeba, the parent cell nuclei divided into two which is followed by the equal cytoplasmic division. The result is the formation of two new daughter cell from the old parent cell with each nuclei i.e., one cell containing one nuclei. These daughter cell will further behave as parent cell and it itself undergoes the same process and results in formation on new daughter cell.

If an organisms give birth to fully developed young ones they are identified as viviparous. Whereas organism who lay eggs and is hatched in external environment are identified as oviparous. Birds lays eggs and the further development of zygotes occur outside the parents body and when it develops at a certain stage it hatches out. This is an example of oviparous. In case of mammals the zygotes and developed inside females body and when it attains a certain stage of development it is expelled from the female’s body.

(a) Zygote

(b) Sperm

(c) Fetus or a baby

The environment on terrestrial land keeps on changing than that of the marine environment. So inorder to increase the survival chance of the fertilization (internal environment is nearly constant) terrestrial animals’ fertilization takes place internally.

A) testis- production of sperms.

B) fallopian tube – captures mature ova after it is released from the ovary and provides the site of fertilization.

C) sperm – male gamete that fertilizes female gamete ova.

D) fertilization – one of the sperm fertilizes ova and results in zygote formation which will further developed into young ones.

Metamorphosis is the process by which the immature forms develop into an adult. The adult male and female produces gametes which are haploid (n). the gametes then fertilize and form a zygote (2n). After 1-2 days of fertilization, the zygote will develop into a larva which is segmented, have mouth hooks, and actively feed. after the larval stage comes the pupa stage in which the body is enclosed in a puparium (outer hard shell) and is inactive and immature. After the pupa states the adult comes out from the puparium by breaking it.

If all organisms stop the process of reproduction the there will be no organism left and it will lead to extinction.

The tadpole is the intermediate stage in the life cycle of a frog. So the tadpole that Kavitha has collected will develop into an adult frog.

MALE REPRODUCTIVE SYSTEM

Adult frogs are carnivores whereas tadpole are herbivores.

Before keeping pigeon squab one must know everything about them live the conditions in which they grow, feeding habits, breeding habits and should take a proper check on the environment.

By the action of Ritwik, we can say that he has an interest in birds and like to keep them.

I would have done the same what ritwik has done.