Ratio between parental types and recombinants in a typical dihybrid cross conducted by Mendel is ___.
5:3
In a cross involving different seed shape alleles (round, R, and wrinkled, r) and different seed color alleles (yellow, Y, and green, y), four types of gametes are expected: RY, Ry, rY, and ry. Therefore, in the F2 generation there are 16 possible combinations of alleles, each of them equally probable. The F2 progeny of dihybrid cross exhibit 4 different phenotypes. Yellow round (9) and green wrinkled (1) are parental combinations. Yellow wrinkled (3) and green round (3) are recombinants. Thus, the ratio becomes (9+1):(3+3) = 10:6, which when simplified is 5:3.