grain clour in wheat isdetermined by three pairs if polygenes. Following the cross AABBCC (dark colour) `xx` aabbcc (light colour), in `F_(2)` generation what proportion of the progeny likely to resemble either parent

Options

A. none
B. less than 5 percent
C. one third
D. half.

Answer

B

Explanation

Polygene results in quantitative inheritance. Quantitative inheritance is characterised by occurensce of intermediate forms between the parental type. There will be 7 (1:6 :15:20:15:6:1) phenotypes when three polygene pairs are involved. The total number of progeny would be 64. Out of these sixty four only two will be likely to resenble either parents. Hence their proportion in `F_(1)` generation would be `3 cdot 12` i.e. less than five per cent.