Question

A homozygous Tall plant (T) bearing red coloured (R) flowers is

crossed with a homozygous Dwarf plant (t) bearing white flowers (r):-

(1) Give the Genotype and Phenotype of the F1 generation.

(2) Give the possible combinations of the gametes that can be

obtained from the F1 hybrid.

(3) Give the dihybrid ratio and the phenotype of the offsprings of

the F2 generation when two plants of the F1 generation above

are crossed.

Answer 1

When homozygous tall plant bearing red flowers (TTRR) are crossed with homozygous dwarf plant bearing white flowers (ttrr) are crossed :-
1.Gametes formed by TTRR will be TR
2.Gametes formed by ttrr will be tr
The F1 plants will be all Tall plants bearing Red flowers as:-
Gene for tallness T is dominant on gene for dwarfness t and gene for Red flowers R is dominant on gene for white flowers r
All F1 plants will be TtRr

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When F1 plants TtRr are selfpollinated
The Gametes formed by these plants will be of 4 types
1.TR 2.Tr
3.tR 4.tr
When these 4 types of Gametes unite
There will be 4 types of Phenotypes
1.Tall plants bearing Red flowers 9
2.Tall plants bearing White flowers 3
3 Dwarf plants bearing Red flowers 3
4.Dwarf plan beari White flowers 1
So Phenotypic ratio of F2 plants as described above will be
9:3:3:1
Hope this description will help you.
Thanks...

Answer 2

Hey mate !


hoping this helps you