MONOHYBRID EXPERIMENT AND LAWS

For doing monohybrid experiment Mendel took one pair of contrasting characters from his selected seven pairs of contrasting characters.As Maendel took one pair so it is known as Mono and crossing as hybrid.From the crossing the ratio that is obtained, he named it as monohybrid ratio and it is 3:1

   7 pairs of characters that Mendel took

First experiment in monohybrid cross he took the pair Height. Height has two contrasting characters one is tall and other is dwarf. For tall he gave the symbol TT which is dominant and dwarf is recessive so he used the small letters of dominant ie. tt.

From the monohybrid cross Mendel formulated two laws ie. Law of Dominance  and Law of segregation.

Law of Dominance- Mendel stated the law in this way- One factor in a pair may express itself and prevent the expression of other. The factor that  expressed itself was described by Mendel as dominant factor and unexpressed one is the recessive factor.

That means that character from father and mother come through gametes. Gametes unit to form zygote and later on leads to the formation of an organism. Sometimes character of father is dominant and sometimes mother's character. The dominant character is expressed in the F1 generation. F1 means first filial generation ie son or daughter.

Law of Segregation:  Segregate means  to separate. In the F1 generation we found that the character is tall and it comes from Tt . But these two allele never get mixed up or are contaminated, they simply remain together and has a tendency to get separated. And this separation occur in the F2 generation, where we find the parental characters to  reappear ie. TT and  tt. This is segregation.

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