Asked in ETEA MDCAT 2008 2008Moderate

In which case the genotypic and.phenolypic ratio·will be 1:2:1?

Correct answer: B. Option B: Incomplete dominance

  • A. Option A: Complete-dominance
  • B. Option B: Incomplete dominance
  • C. Option C: Co-dominance
  • D. Option D: None

Explanation

The correct answer is Option B: Incomplete dominance. In cases of incomplete dominance, the heterozygous offspring exhibit a phenotype that is a blend of the two homozygous phenotypes, leading to a genotypic ratio of 1:2:1 and a corresponding phenotypic ratio of 1:2:1. This is distinct from complete dominance, where one allele masks the other (Option A), resulting in a 3:1 phenotypic ratio. Co-dominance (Option C) allows both alleles to be fully expressed, but does not yield a 1:2:1 ratio. Lastly, Option D is incorrect because incomplete dominance does indeed fulfill the condition specified in the question.

Last updated

About Mendel's Laws of Inheritance

Mendelian inheritance explains how alleles separate into gametes and assort during reproduction, producing predictable genotype and phenotype ratios. Questions cover dominance, recessiveness, homozygous and heterozygous conditions, the laws of segregation and independent assortment, monohybrid and dihybrid crosses, test crosses and the limits caused by linked genes.

Practise Inheritance

1,238 free Inheritance MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Exams that ask Biology questions like this

Biology is on 6 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

Related questions