How are genes inherited

The sperm and egg each contain 23 chromosomes that carry the genetic material of the parents. As human cells contain 46 chromosomes, once the egg and sperm fuse, their chromosomes join to provide the fertilized cell with a full complement of chromosomes. Each egg and sperm carries its own unique set of genes in the

chromosomes, which means that the resulting baby has its own individual genetic makeup. The exception is identical twins; they result from one egg and sperm and inherit the same genetic code