When the sperm and the egg merge together to create a zygote. Happens in the fallopian tube/oviduct.
After fertilization the single cell (aka. Zygote) will divide using the process of mitosis to make a multicellular organism
the cells will become different in structure and function. This happens because only certain genes are expressed in the cell.
2 dominant genes
one dominant and one recessive gene
Two recessive genes
Is used to show the possible allele combinations that can result.