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प्रश्न
Assertion: When the two genes in a dihybrid cross are situated on the same chromosome, the proportion of parental gene combinations is much higher than the nonparental type.
Reason: Higher parental gene combinations can be attributed to crossing over between two genes.
विकल्प
Both A and R are true and R is the correct explanation of A.
Both A and R are true and R is not the correct explanation of A.
A is true but R is false.
A is false but R is true.
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उत्तर
A is true but R is false.
Explanation:
Due to the decreased likelihood of crossing over, parental gene combinations occur more frequently than recombinant forms when two genes are on the same chromosome (linked genes). Higher parental gene combinations, however, result from linkage rather than crossing over. Instead of increasing parental kinds, crossing over increases recombinant types.
संबंधित प्रश्न
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 F2 generation.
(2) Give the possible combinations of the gametes that can be obtained from the F2 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.
The physical expression of a gene is called ______.
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What are the reasons for Mendel’s successes in his breeding experiment?
Two linked genes a and b show 20% recombination. The individuals of a dihybrid cross between ++ /++ × ab/ab shall show gametes ______.
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According to the evolutionary theory, formation of a new species is generally due to
Two pea plants - one with round yellow seeds (RRYY) and another with wrinkled green (rryy) seeds produce F1 progeny that have round, yellow (RrYy) seeds.
When F1 plants are self-pollinated, which new combination of characters is expected in F2 progeny? How many seeds with these new combinations of characters will be produced when a total 160 seeds are produced in F2 generation? Explain with reason.
Which of the following statement is not correct for two genes that show 50% recombination frequency?
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