Question

what are the similarities and differences between the 3 stages of prenatal development? (pre-embryonic, embryonic, fetal)

Answer 1

Prenatal development means the process of developing a zygote into an embryo and later into foetus.Prenatal development is also known as antenatal development.Three stages in antenal development inclkudes pre embyonic stage ,embryonic and fetal stage.

Pre embryonic stage

It refers to the first two weeks of prenatal stage.In this stage the fetus is called as an embryo.In this period the single cell zygote got divisions and goes into a process cell differentiation.

Embryonic stage

This is the period from third week to eighth week of development.This is a stage of organogenesis.In this the ectoderm,endoderm and mesoderm of the embryo develops into organs.These three layers are called germ layers of the embryo..

Fetal stage

It starts from the beginning of the ninth week to 38 weeks,which is an average time of birth.

Similarities are both the embryo and fetus is developing baby inside the womb.Embryo is the first stage of fetus where organs of fetus are developed from the germ layers of embryo.