If a plant is heterozygous for tallness, the $${F_2}$$ generation has both tall and dwarf plants. This proves the principle of
Correct option is B. Segregation
- According to the law of dominance, a trait is represented by two contrasting factors of a gene in a heterozygous individual; only dominant trait is expressed, irrespective of the presence of both factors, in a heterozygous individual.
- It does not tell about the reappearance of the missing trait in $$F_2$$ generation. The law of segregation states that the two factors for a trait, present together in a heterozygous individual, do not get mixed and are separated during gametogenesis.
- Thus each gamete receives one allele for a trait and two types of gametes are formed; 50% gametes carry factor for dominance and 50% carry the recessive factor. Random fusion of these gametes leads to the presence of both recessive and dominant individuals in $$F_2$$ generation.
- Law of independent assortment tells about segregation and distribution of factors governing two different traits; not about segregation of factors of one trait. Incomplete dominance is the condition when none of the factors of a gene is dominant and the phenotype of a heterozygous dominant individual is a blend of dominant and recessive traits.
- It affects the phenotype of $$F_1$$ individuals, not that of $$F_2$$. Thus, the correct answer is option B.