Question

A Mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. The progeny all bore violet flowers, but almost half of them were short. This suggests that the genetic make-up of the tall parent can be depicted as

• A. TTWW
• B. TTww
• C. TtWW
• D. TtWw

Answer 1

Answer: (C)

TtWW

Answer 2

The genetic make-up of the tall parent can be depicted as TtWW Since all the progeny bore violet flowers, it means that the tall plant having violet flowers has WW genotype for violet flower colour. Since the progeny is both tall and short, the parent plant was not a pure tall plant. Its genotype must be Tt.
Therefore, the cross involved in the given question is
TtWw×ttww
$\downarrow$
TtWw−ttww

Therefore, half the progeny is tall, but all of them have violet flowers.