What is a recessive gene?
With the birth of a child, it gets its genes from both parents. Some genes 'override' other genes. Using hair color as instance:
If single parent is blond (Pb) and one parent is black hair (Pd), blond would be the recessive gene, and dark would be the dominant gene. Meaning:
Pb x Pb = Blond Pd x Pd = Dark Pb x Pd = Dark Pd x Pb = Dark