A plant with red flowers was crossed with another plant with yellow flowers. If F 1 showed all flowers orange in colour, explain the inheritance.

A plant with red flowers was crossed with another plant with yellow flowers. If F 1 showed all orange flowers, it means that neither of the alleles is dominant over the other or in other words, it is a case of incomplete dominance. In the case of incomplete dominance, the phenotype of a heterozygous organism is intermediate of both the phenotypes as both alleles are partially expressed. When the F 1 hybrid is self crossed, it gives a phenotype and genotype ratio of 1:2:1 in F 2 generation. (Let R be the allele for red flower and r for yellow flower) F 2 phenotype ratio - Red: Orange: Yellow is 1: 2: 1. F 2 genotype ratio - RR: Rr: rr is 1: 2: 1.

Co-dominance is a type of inheritance where two different alleles express themselves together when present in the heterozygous condition. For example- Allele I A and I B are codominant alleles. When the genotype is I A I B , the blood group of the person is AB.

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Botany Crash Course (Based on Revised Syllabus-2023)>Chapter 2 - Classical Genetics>Exercise>Q 2

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In pea plants, yellow seeds are dominant to green. If a heterozygous yellow seed plant is crossed with a green seeded plant, what ratio of yellow and green seeded plants would you expect in F₁ generation?

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Important Questions on Classical Genetics

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Botany Crash Course (Based on Revised Syllabus-2023)>Chapter 2 - Classical Genetics>Exercise>Q 3

When a single gene produces two effects and one of it is lethal, then the ratio is

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Botany Crash Course (Based on Revised Syllabus-2023)>Chapter 2 - Classical Genetics>Exercise>Q 4

Explain Co-dominance with an example.

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Botany Crash Course (Based on Revised Syllabus-2023)>Chapter 2 - Classical Genetics>Exercise>Q 5

Explain Incomplete dominance with an example.

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Botany Crash Course (Based on Revised Syllabus-2023)>Chapter 2 - Classical Genetics>Exercise>Q 6

In a Mendelian monohybrid cross, the F₂ generation shows identical genotypic and phenotypic ratios. What does it tell us about the nature of alleles involved? Justify your answer.

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Botany Crash Course (Based on Revised Syllabus-2023)>Chapter 2 - Classical Genetics>Exercise>Q 7

Can a child have blood group O if his parents have blood group 'A' and 'B'? Explain.

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Botany Crash Course (Based on Revised Syllabus-2023)>Chapter 2 - Classical Genetics>Exercise>Q 8

A plant with red flowers was crossed with another plant with yellow flowers. If F₁showed all flowers orange in colour, explain the inheritance.

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