Question

Explain the law of dominance using a monohybrid cross.

Answer 1

The power one trait holds over another by appearing in the next generation and preventing the other trait from appearing in the next generation of the individuals. It involves only the single character of an individual.

Complete answer:
Mendel proposed three laws of inheritance:
-Law of Dominance
-Law of Segregation
-Law of Independent Assortment
Law of Dominance using monohybrid cross
According to Mendel's law of dominance “when parents with pure contrasting traits are crossed together, only one form of trait appears in the next generation. The hybrid offspring will exhibit only the dominant trait in the phenotype. “
The Law of Dominance is known as the first law of inheritance. In this law, it is explained that each of the characters or traits is controlled by various units called factors, which occur in pairs. If the pair is heterozygous, one will always dominate the other.
A monohybrid cross of a parent having tallness (TT) and dwarfness (tt) as a single trait shows Mendel’s law of dominance.
The ratio obtained in the F1 generation is 3:1, indicating that out of 4 all the plants are tall. There is no dwarf plant in the F1 generation since ‘T’ is a dominant trait of tallness over ‘t’ which is the recessive trait responsible for dwarfness.
These offsprings are hybrid with only one dominant trait while the trait of the other parent which is dwarfness did not show up.

Note:
Gregor Johanne Mendel was the founder and father of genetics. He conducted many experiments on the pea plant and observed their patterns of inheritance front one generation to another and gave three laws of inheritance.