Some important formula

S.no	For	Formula
1	Number of different gametes	2n (n=no of heterozygots)
2	No. Of individual in the perfect F2 population	4n
3	No of different genotype in F2 population	3n
4	No. Of different homozygous genotype in F2	2n
5	No. Of different heterozygous genotype in F2	3n-2n
6	No of different phenotype in F2	2n
7	No of linkage group	n (haploid)
8	No of bar body	x-1
9	No of primary trisomy	n(haploid)
10	No of secondary trisomy	2n