Solution:-

(1) Egg (ovum) – Unfertilised stage, released from an ovary

(2) Zygote – Fertilised egg, 1-cell state.

(3) Morula – A spherical mass of cells, resulting from the repeated division of the zygote.

(4) Blastocyst – A hollow sphere of cells with a single cellular layer surrounding it (trophoblast) and a centrally projecting core cell mass. Attaches to the uterine wall..

(5) Embryo – A microscopic organism the size of a huge pea bears little resemblance to a person.

(6) Advanced embryo – Heart and blood vessels have formed

(7) Foetus – Limbs have begun to appear. There’s a similarity to a perfect human being.

(8) Infant – Born at the end of nearly 40 weeks.