Difference Between Monohybrid vs. Dihybrid

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Main Difference

Hybrid is a word use for a mixed breed, regarding biology, the offspring of two organisms like plants or animal of different species is called a hybrid. One of a common example of a hybrid is Mule that is a hybrid, which comes as a result of the cross between of donkey and horse. Monohybrid is a hybrid that is heterozygous for a particular gene. And a dihybrid is a hybrid that is heterozygous for alleles of two different genes. The key difference in monohybrid and dihybrid is of genetic arrangement. Monohybrid parents have only a single trait difference, when they are crossed or breed the process is so called monohybrid cross while in a dihybrid, parents have two trait difference and when they are crossed the process is dihybrid cross. Monohybrid is used to study the inheritance of a single pair of alleles, whereas dihybrid is used to study the inheritance of two pairs of alleles.

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Comparison Chart

MonohybridDihybrid
MeaningMono means single and hybrid stands for a mixed breed.Di means single and hybrid stands for a mixed breed.
Traits in ParentsParents in monohybrid have only single trait difference.Parents in dihybrid have double trait difference.
Used ForMonohybrid cross is used to study the inheritance of single pair alleles.A dihybrid cross is used to study the inheritance of two different alleles.
Genotypically RatioGenotypically ratio of monohybrid is 1:2:1 of F2 generation.Genotypically ratio of dihybrid is 1:2:1:2:4:2:1:2:1.
Phenotypically RatioThe phenotypical ratio of monohybrid is 3:1 of F2 generation.9:3:3:1.
Cross Test RatioCross test ratio of monohybrid is -1:1.-1:1:1:1.

What is Monohybrid?

Mono means single and hybrid stands for a mixed breed. Monohybrid is that type of hybrid in which only a single trait difference is present in the parents; this hybrid has a heterozygous configuration on a specific gene. A monohybrid cross is a cross between two normal organisms from different species to study the inheritance of a single pair of alleles. As a result, it produces some ratios of genotypic, phenotypic and test cross ratio. The genotypic monohybrid ratio of F2 generation is 1:2:1; the phenotypic monohybrid ratio is 3:1 and the test cross ratio in monohybrid cross are -1:1. In a monohybrid cross, the main focus is on phenotype and genotype both. For example, Phenotype of the yellow color plant is (YY), and phenotype of the green color plant is (yy), when they are crossed, the gametes will be heterozygous. The phenotype of two will be yellow, but genotype will be (Yy), one will be (YY) yellow, and one will be (yy) green. The phenotypical ratio will be 3:1 and the genotypically ratio will be 1:2:1.

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What is Dihybrid?

Di means double and hybrid stands for a mixed breed. Dihybrid is that type of hybrid in which there is two trait difference is present in the parents; this hybrid has a heterozygous configuration for alleles of two different genes. A dihybrid cross is a cross between two normal organisms from different species to study the inheritance of two pairs of alleles. As a result, it produces some ratios of genotypic, phenotypic and test cross ratio. The genotypic dihybrid ratio of F2 generation is 1:2:1:2:4:2:1:2:1, the phenotypic dihybrid ratio is 9:3:3:1 and the test cross ratio in dihybrid cross are -1:1:1:1. In a dihybrid cross, two characteristics are crossed together to get final results. For instance, pea shape and its color. One or two Y alleles will give yellow color or phenotype, whereas alleles (yy) will give green color. Here are two more alleles that will give the shape of pea as round or wrinkled. The dominant allele (R) will turn pea to round shape, and allele (r) will turn it into wrinkled shape.

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Monohybrid vs. Dihybrid

  • Mono means single and hybrid stands for a mixed breed, whereas Di means single and hybrid stands for a mixed breed.
  • Parents in monohybrid have only single trait difference while parents in dihybrid have double trait difference.
  • Monohybrid cross is used to study the inheritance of single pair alleles and contrary to that dihybrid cross is used to study the inheritance of two different alleles.
  • Genotypically ratio of monohybrid is 1:2:1 of F2 generation and dihybrid it is 1:2:1:2:4:2:1:2:1.
  • The phenotypical ratio of monohybrid is 3:1 of F2 generation and dihybrid it is 9:3:3:1.
  • Cross test ratio of monohybrid is -1:1 and in dihybrid cross is -1:1:1:1.

Comparison Video