Example of Complete Dominance
If $AA=10$ & $aa=0$, then which of the following is the example of complete dominance-
- $Aa=5$
- $Aa=7$
- $Aa=10$ — Correct Answer
- $Aa=15$
Explanation:
Correct Answer: Aa = 10 (Complete dominance)
In complete dominance, the presence of even a single dominant allele (A) completely masks the recessive allele (a), making the heterozygote phenotypically identical to the dominant homozygote. So Aa = AA = 10.
Complete Summary (AA=10, aa=0)
| Aa Value | Gene Action | Interpretation |
|---|---|---|
| 5 | Additive | No dominance — purely cumulative; Aa exactly at mid-parent value |
| 7 | Incomplete dominance | Partial dominance — Aa between midpoint and AA |
| 10 | Complete dominance | Aa = AA — dominant allele fully masks recessive |
| 15 | Over-dominance | Aa > AA — heterozygote is superior to all homozygotes |
F₂ phenotypic ratio in complete dominance (monohybrid): 3:1
F₂ phenotypic ratio in incomplete dominance: 1:2:1
📚 About this Topic — Animal Genetics & Breeding
This multiple choice question is from Animal Genetics & Breeding, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Genetics & Breeding to strengthen your preparation.
