Prenatal Period - This is the time period between pregnancy and birth. The human body, like most animals, develops from a cell that is produced by the union of a male sperm and female ovum. The average time of pre-natal development is about 38 weeks or 9 lunar months. The prenatal period is usually divided into three stages i.e., the Germinal Stage, Embryonic Stage and Foetal Stage.
(i)
Germinal Stage – This stage runs from the
conception (sperm cell meets with the ovum) to two weeks where a zygote is
formed. At this stage the multiplying cells take the shape of a ball that
starts receiving oxygen and other vital nutrients.
(ii)
Embryonic Stage – The ball of cells is now known as
an embryo. The beginning of the third week after conception marks the
start of the embryonic period, a time when the ball of cells becomes distinct
as a human. The embryonic stage plays an important role in the development of
the brain. At this stage, construction of heart and blood vessels and other
specialized organs such as eyes, ears, nose etc. begins. The basic structure of
the brain and nervous system is also determined in this phase
(verywellmind.com).
(iii)
Foetal Stage – This phase starts from 9th week
(approximately 2 months) and continues till birth. In this stage, physical
systems developed during the embryonic stage develops further. The internal
processes of brain which are important for the future psychological characteristic
also develops during this stage. In this stage, the foetus prepares itself for
external life.
No comments:
Post a Comment