Meiosis
Meiosis is a type of cellular division in which one cell with 46 chromosomes splits into two cells, each with 23 chromosomes. It is through this process that the male sperm and female ovum (egg) are formed.
Meiosis allows the sperm and egg to contribute half of your baby’s genetic information to the 46 chromosome zygote which forms after fertilisation and undergoes mitosis throughout your pregnancy.
If meiosis does not occur properly, such that each sperm or egg has one extra or one less chromosome than it should, a chromosomal abnormality results. This is known as a trisomy (1 extra chromosome) or a monosomy (minus 1 chromosome).
Tags: chromosomal abnormality, chromosomal development, egg, fertilisation, meiosis, mitosis, pregnancy, pregnant, sperm, zygote