Fertilisation and pregnancy
Fertilisation is the fusion of a haploid A cell that contains half the normal number of chromosomes.sperm cellThe male sex cell or gamete. nucleus and a haploid egg cellThe female reproductive cell. nucleus to form a diploid A cell that contains the normal number of chromosomes. (normal chromosome number) zygote.
A zygote is the first cell of a new individual. Fertilisation occurs in the oviductA tube in the female reproductive organ through which an egg passes from an ovary to the uterus..
After fertilisation:
- The zygote travels down the oviduct dividing to form a ball of cells embryoAn organism in the early stages of development..
- When the embryo reaches the uterusAlso known as a womb. This is where the fertilised egg (ovum) develops., implantation occurs. This is when the embryo attaches to the thick uterus lining to receive nourishment.
- The placentaThe organ in the uterus of pregnant mammals that allows the transfer of nutrients and waste products between the mother and the fetus through the umbilical cord., umbilical cordThe cord that connects the foetus to the placenta. It contains blood vessels., amnionBag surrounding the foetus in the uterus and containing the amniotic fluid. and amniotic fluidThe fluid surrounding a foetus that cushions it. form.
