Q14 of 58 Page 1

A blue colour flower plant denoted by BB is crossbred with a white colour flower plant denoted by ww.

(a) State the colour of flower we would expectintheirF1 progeny.


(b)Write the percentage of plants bearing white flower inF2generation when the flowers ofF1 plants were selfed.


(c) State the expected ratio of the genotype BB and Bw intheF2progeny.

(a) In the first generation i.e. in F1 generation, all the flower plants will be of blue color. It can be shown as follows:

Untitled.png


(b) When flowers of f1 generation are self pollinated:


Untitled.png


So, in F2 generation, there will be three blue Flowers and one white flower. So they ratio of blue flower plant to ratio of white flower plant is 3:1


But we need to find the ration percentage of white flower which is calculated as follows:


Percentage =


Percentage =


So, Ratio percentage of white flower plant is 25%


(c) The expected ratio of the genotypes BB and Bb in the F2 progeny is as follows:


Untitled.png


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