26. In an experiment involving mapping of 3 genes (a, b andc) in Drosophila, a three point test cross is carried out.The parental cross was AAbbCCXaaBBcc. The genotypesof the double […]
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CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Progeny Proportions in Haploid Organisms
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Understanding Linkage or Independent Assortment from Test Cross
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Understanding Recombination in Drosophila melanogaster
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Calculating Genetic Distance Between Brown Eye and Curled Wing Genes in Drosophila Melanogaster
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Understanding Parental and Recombinant Progeny in Linkage Maps
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Maximum Frequency of Recombination Between Two Loci Explained
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Somatic recombination and mosaic yellow patches
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Genetic Cross Analysis of White-Eyed and Crossveinless Traits in Drosophila melanogaster
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 […]
CSIR NET Life Science Previous Year Questions and Solution on GENE MAPPING METHODS
Understanding Genetic Recombination in Bacteriophage Mutations Affecting Plaque Morphology
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. […]
