GENOTYPE DEFINITION

       Look at the word, it contains the root gene.  Since you got at least one gene for every trait in
       your body from each of your parents, you should have at least TWO genes for every trait. 
       Those two genes are called your genotype.  In the case of the chlorophyll gene pair, the plant
       genotypes contain two genes for this trait.  The first gene is either a C or a c.  The second gene
       is also a C or a c. 

       There are therefore three possible genotypes for each plant parent:
       These three possible genotypes are __ __, __ __, & __ __.   (Remember that Cc and cC are
        really the same gene pair.)  This is from the commutative law of algebra.  But genetics is a
        mathematical branch of biology so we follow the laws of algebra.