Question

State the Mendelian principle which can be derived from a dihybrid cross and not from monohybrid cross.

Answer 1

Third law of the Mendel or Law of the Independent Assortment can be derived from the Dihybrid cross and not from the monohybrid cross.

Monohybrid cross can be only use to derive the Law of Dominance and Law of the Segregation. (First and second law)

Law of Independent Assortment of the Mendel says that, '' The Law of Independent Assortment is a principle of inheritance that states that each heritable allele (contrasting pair of gene) is inherited independently of one another. ''

Phenotype ratio = 9 : 3 : 3 : 1

Genotype Ratio = 4 : 2 : 2 : 1 : 1 : 2 : 1 : 2 : 1

Hope it helps.

Answer 2

The Mendel's law of independent assortment.. which states "that factors for contrasting characters(allelic genes) do not blend with EACH other but seggerate (up to this is law of seggregation which is derived from the monohybrid cross) but pass on to different gametes and express them(3rd law... law of independent assortment)