Please tell

Yellow               Green

YY              *            yy ............................ Parents

Y                 *            y...............................  gametes

When crossed,  Yy  (hybrid yellow) ................................  F1

The gametes of F1 when selfed,

            

	Y	y
Y	YY (Pure yellow)	Yy (Hybrid yellow)
y	Yy (Hybrid yellow)	yy (Pure green)

3 yellow : 1 green.

 Dominance is the expression of a trait in the heterozygous condition. It can be defined as the interaction between two alleles at the same locus where one partially or completely prevents the phenotypic expression of the other when present in the heterozygous state.