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Principles of Inheritance and Variation — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYPrinciples of Inheritance and Variation3 Marks
Question
Explain the laws that Mendel derived from his monohybrid crosses.
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Answer

Law of dominance and law of segregation are the two laws, Mendel derived from his monohybrid crosses.
  1. Law of dominance explains that in a dissimilar pair of factors of a trait, one of them expresses itself (dominant) and the other remains hidden (recessive).
  • It also explains the expression of both the traits in the F, progeny, in a ratio of 3 : 1.
  1. Law of segregation states that the members of an allelic pair that remained together in the parent/ hybrid, segregate during gamete formation and enter different gametes.
  • A homozygous parent produces all gametes that are similar while the heterozygous one produces two kinds of gametes, each having one allele for a trait.

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