Example of Monohybrid Cross
Example of a monohybrid cross using pea plants with purple (P) and white (p) flower color as the trait is as follows;
Parental Generation (P):
- One parent has purple flowers (PP, homozygous dominant).
- The other parent has white flowers (pp, homozygous recessive).
F1 Generation:
- Cross the two parents.
- All the offspring in the F1 generation will have purple flowers (Pp, heterozygous).
F2 Generation:
- Allow the F1 generation to self-pollinate or cross-pollinate.
- Observe the offspring in the F2 generation.
- 3:1 phenotypic ratio
- Three-fourths (75%) will have purple flowers (PP or Pp).
- One-fourth (25%) will have white flowers (pp).
This monohybrid cross demonstrates Mendel’s law of dominance, where the dominant trait (purple flowers) masks the expression of the recessive trait (white flowers) in the F1 generation, but the recessive trait reappears in the F2 generation in a 3:1 ratio.
Monohybrid Cross – Inheritance of One Gene
Monohybrid cross occurs when two organisms with contrasting variations at a particular genetic locus are crossed. The traits being studied are influenced by multiple variations at a single gene location. The resulting offspring, known as the F1 generation, will all be heterozygous and express the dominant trait, masking the recessive trait. The monohybrid cross demonstrates Mendel’s law of dominance.
Table of Content
- Monohybrid Definition
- What is Monohybrid Cross?
- How to carry out a Monohybrid cross?
- Example of Monohybrid Cross
- Huntington’s Disease
- FAQs on Monohybrid Cross