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प्रश्न
Give an account of incomplete dominance with a suitable example.
उत्तर
Incomplete dominance:
- Incomplete dominance is a deviation from Mendel’s law of dominance.
- In incomplete dominance, both the alleles (genes) of an allelomorphic pair express themselves partially.
- One allele (gene) cannot suppress the expression of the other allele (gene) completely.
- In such a case, there is an intermediate expression in the F1 hybrid.
- In Mirabilis jalapa, if a red-flowered (RR) plant is crossed with a white-flowered (rr) plant, then F1 offspring have pink (Rr) flowers.
F2 Generation: Selfing of F1
Result:
Genotypic ratio - 1 RR : 2 Rr : 1rr
Phenotypic ratio - 1 Red: 2 Pink :1 White
APPEARS IN
संबंधित प्रश्न
The F2 progeny of a monohybrid cross showed phenotypic and genotypic ratio as 1:2:1 unlike that the Mendel’s monohybrid F2 ratio. With the help of a suitable example, work out a cross and explain how it is possible.
According to Mendel alleles have the following character ______.
The pairs of contrasting character (traits) of Mendel are called ______.
The crossing of F1 to homozygous recessive parent is called ______.
In a monohybrid cross between two heterozygous individuals, percentage of pure homozygous individuals obtained in F1 generation will be ______.
Which of the following crosses will give tall and dwarf pea plants in same proportions?
Mendel’s law of independent assortment does not hold true for the genes that are located closely on ______.
Read the following and answer from given below:
Prashant wanted to find the genotype of a pea plant bearing purple coloured flowers in his kitchen garden. For this, he crossed purple-flowered plants with white-flowered plants. As a result, all plants which were produced had purple flowers only. Upon selfing these plants, 75 purple flower plants and 25 white flowers plants were produced. Now, he can determine the genotype of a purple-flowered plant by crossing it with a white-flowered plant.
The character i.e., the purple colour of the flowers that appeared in the first filial generation is called ______
In the following crosses write the characteristics of the progeny
| Cross | Progeny |
| (a) RR YY × RR YY | __________________ |
| Round, yellow Round, yellow | __________________ |
| (b) Rr Yy × Rr Yy | __________________ |
| Round, yellow Round, yellow | __________________ |
| (c) rr yy × rr yy | __________________ |
| wrinkled, green wrinkled, green | __________________ |
| (d) RR YY × rr yy | __________________ |
| Round, yellow wrinkled green | __________________ |
Give the basic features of the mechanism of inheritance.
