The first step in the process of reproduction is diffusion of a sperm and ovum and sperm come in contact with egg one of the sperm a fuse with the execution of the egg and sperm is called fertilization during fertilization The nuclei of sperm and eggs used to form a single nucleus is result in the formation of fertilized egg or zygote the process of fertilization is of an meeting of an egg cell from the mother and sperm from the father so that the individual inherits some characteristics from the mother and some from the father fertilization results in the formation of zygote with begin to developed into an embryo the zygote divides repeatedly to give rise to a ball of cells the cell then begin to formgroup' that develop into different tissues and organs of the body is developing a structure is termed as an embryo gets embedded In The Wall of the uterus for further development the embryo continues to develop in the uterus is gradually develop body parts like hand leg head eyes ears etc the a stage of the embryo in which all the body parts can identify is called Foetus when the development of foetus is complete the mother gives birth to the baby