Two true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high. a) What would be the size and genotype of the F1 from a cross between a true-breeding 11 cm plant and a true-breeding 47 cm plant? b) The F1 from (b) is then crossed to give an F2. What proportion would you expect in the F2 of each extreme phenotype? c) In a cross between a 29cm plant and a 20cm plant what would be the genotypes giving the smallest number of different phenotypes? specify the phenotypes observed.
1) Two true-breeding varieties of maize, one 11 cm high and the other 47 cm high were crossed and the resultant F1 hybrids were then crossed to generate the F2 . In the F2 there were a total of 13,923 plants with a continuous variation in heights between the two extremes and with only 3 plants as large as 47 cm high and 5 plants of 11 cm high.
a) What would be the size and genotype of the F1 from a cross between a true-breeding 11 cm plant and a true-breeding 47 cm plant?
b) The F1 from (b) is then crossed to give an F2. What proportion would you expect in the F2 of each extreme phenotype?
c) In a cross between a 29cm plant and a 20cm plant what would be the genotypes giving the smallest number of different
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