The $F_2$ dihybirid ratio $9 : 3 : 4$ is explained on the basis of
Epistatic gene
Supplementary gene
Allelic interaction
Complementary gene interaction
Fraternal twins are produced when
In a mutational event, when adenine is replaced by guanine, it is the case of
The phenomenon in which an allele of one gene suppresses the activity of an allele of another gene is known as
Linkage was first suggested by
Which one of the following is not a mutagen