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In a haploid organism, the loci A/a and D/d are 8 map units apart. In a cross Ad X aD, what will be the proportion of each of the following […]

A test cross was made with phenotypically wild type Drosophila files hiving genes for sepia eye and curled wing in heterozygous condition. The following results were obtained: Wild type 400 […]

23. Which statement is true for Drosophila melanogaster? (1) female are achiasmatic (2) recombination does not occur during male meiosis (3) recombination does not during female meiosis (4) males show […]

A cross was made between pure wild type males and brown eyed curled winged females of D. melanogaster. The F1 females were test crossed. The F2 progeny obtained was as […]

21. In a linkage map, two genes A and B, are 70 CM apart. If individuals heterozygous for both the genes are test crossed number of progeny with parental phenotype […]

20. The maximum frequency of recombination that can occur between two loci is (1) 25%         (2) 50% (3) 75%         (4) 100% The maximum frequency of recombination that can occur between […]

19. In an organism, allele governs grey body colour,while its mutant allele a gives yellow body colour.Further, presence of allele gives long and thin hairswhile b allele gives rise to […]

18. Assume that the genes w+ and cv+ are located 20 CM apart on the X chromosome of Drosophila melanogaster. Mutations in w+and cv+ give rise to white eyes and […]

17. Two mutations were isolated in bacteriophage, one causing clear plaque (c) and the other causing minute plaque (m). The genes responsible for these two mutations are 9 CM apart. […]

16. Two genes a and b are located at a distance of 10 cM. Individuals of the genotype AaBb are sib-mated. The two genes are linked in trans. What percentage […]