Class 12 NEET Biology Principles of Inheritance and Variation Questions Part 1

Linkage/ Cross over/ Chromosome maps is a graphic representation of relative positions/ order and relative distances of genes in a chromosome in the form of line like a linear road map depicting different places and their relative distances without giving exact mileage. It is based on Morgan's hypothesis (1911) that frequency of crossing over\/recombination between two linked genes is directly proportional to the physical distance between the two. 1 map unit or centrimorgan is equivalent to 1% recombination between two genes. Percentage of crossing over between a and b is 20% so they are 20 map distance apart and b and c are 28 map distance apart. So, that correct sequence of genes on chromosomes will be as