CBSE 2025 · Region 6 · Set 1 · Q13 · 1 mark
Assertion (A) : In dihybrid crosses involving sex-linked genes in Drosophila generation of non-parental gene combinations are observed. Reason $\displaystyle (R)$ : Two genes present on different chromosomes show linkage and recombination in Drosophila.
Official answer
From CBSE’s own marking scheme for this paper.
(C)
Assertion (A) is true, but Reason (R) is false.
Principles of Inheritance and VariationInheritance of Two GenesAnalyseassertion_reasonmedium
Practice Principles of Inheritance and Variation →All Principles of Inheritance and Variation questions
More from Principles of Inheritance and Variation
- Using a Punnett square workout the distribution of an autosomal phenotypic feature in the first filial…2025 · asked 3×
- By using Punnett square depict the genotypes and phenotypes of test crosses (where green pod colour (G) is…2023 · asked 3×
- The following pedigree chart shows the inheritance of a genetic disorder up to three generations of a family.…2023 · asked 3×
- Write the types and locations of the genes causing thalassemia in humans. State the cause and symptoms of the…2026 · asked 3×
- A person with trisomy of 21^ st chromosome shows (i) Furrowed tongue (ii) Characteristic palm crease (iii)…2024 · asked 3×
- The chromosome number is fixed for all normal organisms leading to species specification whereas any…2023 · asked 3×
- A student performed some crosses in plants and represented the result in the form of bar graphs as shown…2026 · asked 3×
- Assertion: ABO blood grouping in humans is an example of multiple allelism. Reason (R): More than two genes…2025 · asked 3×
CBSE Class 12 Biology past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.