Question

What do you understand by Monohybrid and Dihybrid cross? Describe in detail with example.

Answer 1

The cross is the breeding among two individuals which results in the formation of the offsprings as the genetic material combines. The offspring constitute the genetic material from both the parents. The cross occurs between the individuals that are compatible and are closely related.

Complete step by step answer:

Monohybrid cross	Dihybrid cross
Two organisms of the pure line are crossed to study the inheritance of a single allelic pair.	Two organisms of the pure line are crossed to study the inheritance of two pairs of alleles.
It includes two types of gametes.	It includes four types of gametes.
Four offsprings are produced.	Sixteen offspring are produced.
The phenotypic ratio is 3:1	The phenotypic ratio is 9:3:3:1
The genotypic ratio is 1:2:1	Genotypic ratio is 1:2:1:2:4:2:1:2:1
Example- Cross between round and wrinkled seeds of the pea plant.	Example- Cross between round and yellow and wrinkled and green pea seeds.

Additional information
A monohybrid cross of a parent having yellow seeds (YY) and green seeds (yy) as a single trait shows Mendel’s law of dominance.
The cross between the organisms that involves the two traits is known as the dihybrid cross and was first discovered by Mendel.
-The cross between two parent species TTRR and ttrr give the four identical ${ F }_{ 1 }$ progeny as all TtRr. The offsprings generated in the next generations will be different in number.

Note:
Genotype is considered a genetic combination of traits in an organism. The three types of genotypes that are found are homozygous dominant, homozygous recessive, and heterozygous. Phenotype is considered as the physical appearance of traits in an organism that we can see or observe through our eyes like height, eye color, etc.