NCERT · Class 10 · Science · HeredityIn a dihybrid cross between heterozygous plants (RrYy × RrYy) where R = round, r = wrinkled, Y = yellow, y = green, what is the phenotypic ratio of the F₂ generation?
Step-by-Step Solution
Answer: The phenotypic ratio is 9 : 3 : 3 : 1.
Explanation: The classic Mendelian dihybrid cross yields nine plants showing both dominant traits (round‑yellow), three showing round‑green, three showing wrinkled‑yellow, and one showing wrinkled‑green.
Detailed Options Breakdown
Option : 3 : 1
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Heredity.
Option 1: 9 : 3 : 3 : 1 (Correct Answer)
Correct choice. Refer to the step-by-step verified solution guidelines above for details.
Option 2: 1 : 1 : 1 : 1
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Heredity.
Option 3: 9 : 6 : 1
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Heredity.
💡 Study Guide: This question tests core syllabus concepts from Heredity. For formulas, key summaries, and mock exam reference guides, read the full Heredity Revision Notes.