1) Fertilization is the process of fusion of gametes to form a new organism of the same species. When the male gamete (i.e., the sperm) and the female gamete (i.e., the ovum) fuses with each other resulting the formation of a zygote, this process is called as fertilization. The new organism is formed when the zygote divides and forms embryo and this embryo further divides, thus resulting in the formation of the new organism.
6) Internal fertilization is the fusion of an egg/ovum and sperm inside the female body. The type of fertilization that is seen in hen is a type of internal fertilization.
7) Budding is a type of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at a particular site. The small bulb-like projection coming out from the organism's body is called a bud.
8) The ovary is an organ found in the female reproductive system that produces an ovum. When an ovum is released, it travels down the fallopian tube, where it fertilized by a sperm and then the zygote enters into the uterus for further growth into a new organism. Ovary secretes estrogen and progesterone for the development of female reproductive organs and for the development of embryo during pregnancy.
2) The testis is an organ found in the male reproductive system that produces an sperm. Testis is contained in a sac of skin called as scrotum. Testis secretes testosterone for the development of male reproductive organs.
3) A zygote is an eukaryotic cell formed by the fertilization of two gametes. The zygote begins as a single cell but divides rapidly in the following days after fertilization. The zygote's single cell contains 46 chromosomes. It gets 23 chromosomes from the sperm and 23 chromosomes from the ovum.
4) An oviparous animal is one that produces eggs, and the young ones are hatched after being expelled from the body. Many amphibians, birds, fish and reptiles are oviparous and often make nests to protect their eggs.
5) In the process of binary fission, an organism duplicates its genetic material and then divides into two parts (cytokinesis), with each new organism receiving one copy of DNA.