Biology · Variation and Genetics
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A monohybrid cross yielded 3:1 in F2. What could be mode of inheritance?
- A
Segregation
- B
Independent assortment
- C
Both a and b
- D
None of these
The principle of segregation states that each individual has two alleles for each gene, and these alleles segregate during gamete formation, with each gamete receiving only one allele. A 3:1 ratio in the F2 generation of a monohybrid cross suggests that the trait being studied is controlled by a single gene with two alleles and follows a dominant and recessive pattern of inheritance. The dominant allele is expressed in the phenotype of individuals that are homozygous dominant or heterozygous, while the recessive allele is only expressed in individuals that are homozygous recessive. Therefore, the mode of inheritance for the trait being studied is likely to be Mendel's law of segregation.
The principle of segregation states that each individual has two alleles for each gene, and these alleles segregate during gamete formation, with each gamete receiving only one allele. A 3:1 ratio in the F2 generation of a monohybrid cross suggests that the trait being studied is controlled by a single gene with two alleles and follows a dominant and recessive pattern of inheritance. The dominant allele is expressed in the phenotype of individuals that are homozygous dominant or heterozygous, while the recessive allele is only expressed in individuals that are homozygous recessive. Therefore, the mode of inheritance for the trait being studied is likely to be Mendel's law of segregation.
No, the mode of inheritance for a monohybrid cross with a 3:1 ratio in the F2 generation is not an independent assortment. Independent assortment refers to the principle that states that the inheritance of one gene is independent of the inheritance of another gene, and it applies to dihybrid crosses, where two traits are studied at the same time. In a monohybrid cross, only one trait is studied, and the ratio of 3:1 in the F2 generation suggests that the trait is controlled by a single gene with two alleles and follows a dominant and recessive pattern of inheritance. Therefore, the mode of inheritance is likely to be Mendel's law of segregation.
This option is incorrect.Only option A is correct
This option is incorrect. Option A is correct
Tagged under Biology · Variation and Genetics · 2021