A sperm cell from the father and the egg cell from the mother initially fuse to form a structure called zygote.
The terms incipient organism and embryo both allude to the creating infant inside the mother's belly (uterus). The difference among the two terms zygote and fetus is dependent on gestational age.
A fetus is the beginning period of human advancement where organs are basic body structures are framed.
An embryo is named a fetus starting in the eleventh week of pregnancy, which is the ninth week of development after fertilization of the egg.
A zygote is a solitary celled living being coming about because of a fertilized egg. The zygote partitions to turn into a bundle of cells that inevitably embeds in the mass of the uterus.
This bundle of cells, known as a blastocyst, forms into the embryo and placenta.