Question

Find the Phenotypic ratio and Genotypic ratio in F2 generation
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Answer 1

Answer:-

The parents given are:-

TTVV and ttvv

T = Tall ( Dominant )

V = Violet flower ( Dominant )

t = Short ( Recessive )

v = White flower ( Recessive )

Now, for F1 generation.

The gametes are :- TV, TV for the first parent and tv, tv for the second parent.

The progenies will be of genotype :- TtVv

Now, for F2 generation.

The parents:- TtVv and TtVv.

Gametes:- TV, Tv, tV and tv for both of them.

Punnet square:-

$\boxed{\begin{tabular}{c|c|c|c|c}\bf{-} & \bf{TV} & \bf{Tv} & \bf{tV} & \bf{tv}\\\cline{1-5}\bf{TV} & TTVV & TTVv & TtVV & TtVv\\\cline{1-5}\bf{Tv} & TTVv & TTvv & TtVv & Ttvv\\\cline{1-5}\bf{tV} & TtVV & TtVv & ttVV & ttVv\\\cline{1-5}\bf{tv} & TtVv & Ttvv & ttVv & ttvv\end{tabular}}$

Now, PHENOTYPIC RATIO:

Tall with violet flowers = 9

Tall with white flowers = 3

Short with violet flowers = 3

Short with white flowers = 1

Hence, ratio = 9:3:3:1

And, GENOTYPIC RATIO:

TTVV = 1

TTVv = 2

TTvv = 1

TtVV = 2

TtVv = 4

Ttvv = 2

ttVV = 1

ttVv = 2

ttvv = 1

Hence, ratio = 1:2:1:2:4:2:1:2:1