Question

A cross between two individuals results in a ratio of 9 : 3 : 3 : 1 for four possible phenotypes of progeny. This is an example of a :

(a) dihybrid cross (b) monohybrid cross (c) test cross (d) none of these

Answer 1

(a) dihybrid cross

Based upon such observations on dihybrid crosses (crosses between plants differing in two traits) Mendel proposed a second set of generalisations that we call Mendel’s Law of Independent Assortment. The law states that “When two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the other pair of characters”