What is the map distance between two linked genes on a chromosome if the frequency of recombinant offspring in a test cross is ?
Answer and explanation
Correct answer: B. centimorgans ( or ) on the genetic chromosome
- Step 1: Alfred Sturtevant, a student of Morgan, pioneered genetic linkage mapping using recombination frequencies.
- Step 2: He defined one map unit (or centimorgan, ) as the physical distance along a chromosome that corresponds to a recombination frequency of .
- Step 3: Therefore, crossing over between two loci equals exactly .
Answer
centimorgan ( or ).
Why not the others: corresponds to recombination; corresponds to recombination; corresponds to unlinked genes exhibiting independent assortment.
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