A Mendelian experiment consisted of breeding tall TT pea plants bearing violet flowers with short t pea plants bearing white w flowers. The progeny all bore violet W flowers, but almost half of them were short. This suggested that the genetic make-up (or genotype) of the tall parent can be depicted as:

(a) TTWW


(b) TTww


(c) TtWW


(d) TtWw


Give reason for your choice

The genetic makeup of the tall parent can be depicted as (C) TtWW. As the question says, Tall Pea plants bearing violet flowers; Tallness is a dominant trait and is always represented by capital letters so ‘T’ and short/dwarfness is represented by small letters so ‘t’ – hence Tt. Violet Flowers is a dominant trait and is represented by capital letters so ‘W’. The progeny had short plants but no white flowers which means that Violet flowers are being passed on. Therefore, the genotype of the tall parent can be depicted as TtWW. There is a dominant gene for tallness which suppresses the recessive gene for height and for all violet flowers were present in tall pea plant.


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