Stages of growth and development throughout the human lifespan
The individual I have chosen is: Jahseh Dwayne Ricardo Onfroy
Conception is the beginning of a person’s life. A woman will normally produce an egg cell each month, this is usually two weeks after the last menstrual period. This egg cell travels from the ovary where is is released and along the fallopian tube towards the uterus. However, if sexual intercourse takes place when the egg is in the fallopian tube, there will be a possibility of conception and pregnancy. The way this happens is that during sexual intercourse millions of sperm are ejaculated by a man when he orgasms. Out of the millions of sperm only one sperm can fertilise the egg. The process of fertilisation is the joining of the genetic material in the sperm cell with genetic material in the egg cell to conceive a new life.
Week 1 ; 2
Here in the first two weeks of pregnancy the newly fertilised egg makes its way through the fallopian tube and is carried into the uterus. The egg then implants itself in the wall of the uterus.
At three weeks the embryo becomes pear shaped. The embryo will have a rounded head, pointed lower spine and a notochord going along its back.
At four weeks the embryo becomes C shaped and the tail becomes visible . the umbilical cord also forms and the forebrain enlarges.
By the fifth week the embryo will have begun to form all the internal organs. This is a very critical stage of development as the embryo is very vulnerable, especially to harmful substances consumes by the mother, which may lead to defects. Substances that could lead to defects would include alcohol or drugs.
At six weeks the the embryo’s eyes are visible and the mouth, nose and ears are forming. The embryo’s limbs start as tiny buds and after the sixth week the limbs will rapidly grow from these tiny buds.
At eight weeks the face of the embryo becomes more human-like and the head is more upright. Furthermore the tail has gone and the limbs have become jointed. Also at eight weeks the fingers and toes appear and become visible and the embryo will have become a foetus and may have grown to between 3 and 4 cm.
Weeks 9 – 40
During the remaining weeks after the eighth week the foetus and all its organs will steadily continue to grow and develop. By the twentieth week the foetus should have reached about half the length of the baby at birth. Additionally the foetus will be about half its birth weight at thirty-two weeks.