Biology
Make a Punnett square and find out the genotypic and phenotypic ratios of F1 and F2 generations in the progeny of a genetic cross between:
(a) A pure tall (TT) pea plant with a pure dwarf (tt) pea plant.
(b) Red flower variety of pea (RR) with white flower variety of pea (rr).
Genetics
ICSE
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Answer
(a) A pure tall (TT) pea plant with a pure dwarf (tt) pea plant:
F2 Generation:
| Gametes | T | t |
|---|---|---|
| T | TT | Tt |
| t | Tt | tt |
Genotype - 1 (Homozygous tall) : 2 (Heterozygous tall) : 1 (Homozygous dwarf)
Phenotype - 3 (Tall) : 1 (Dwarf)
(b) Red flower variety of pea (RR) with white flower variety of pea (rr):
F2 Generation:
| Gametes | R | r |
|---|---|---|
| R | RR | Rr |
| r | Rr | rr |
Genotype — 1 (Homozygous red) : 2 (Heterozygous red) : 1 (Homozygous white)
Phenotype — 3 (Red) : 1 (White)
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