Foetus is an unborn baby that develops and grows inside the uterus. The developing embryo gradually differentiates into different body parts, such as hands, legs, head and other. Thus, when in the embryo different body parts can be identified, it is called a foetus.

Match the following: Column A Column B Sperm Cat Internal fertilization Frog External fertilization Female Cervix Male

Sperms are haploid gametes that are present in sexually reproducing males. Cats are mammals, and in all mammals, fertilization takes place within the body. Therefore, internal fertilization takes place in cats. Female frogs release their eggs out of the body into the water, which fuses with sperms released by male frogs into the water. Therefore, external fertilization takes place in frogs. Cervix is a part of the female reproductive system. It is a cylinder-shaped neck of tissue that connects the vagina with the uterus. It facilitates the entry of sperms into the uterine cavity, and if sperm fuse with an ovum, the zygote forms. Column A Column B Sperm Male Internal fertilization Cats External fertilization Frog Cervix Female

Amnion, in reptiles, birds, and mammals, a membrane forming a fluid-filled cavity i.e. amniotic sac that encloses the embryo. The amnion of mammalian embryo is derived from ectoderm on the inner side and covered with mesoderm (both are germ layers), it acts as a protective sac along with three other extraembryonic membranes: the chorion, the yolk sac, and the allantois. The amnion contains a thin, transparent fluid in which the embryo is suspended. It provides a cushion against mechanical injury providing a protective environment for the developing embryo.