Question

Mendel proposed that the factor controlling any character is discrete and independent. His proposition was based on the ______.

Options

• observations that the offspring of a cross made between the plants having two contrasting characters shows only one character without any blending

• self-pollination of F₁ offsprings

• cross pollination of F₁ generation with recessive parent

• results of F₃ generation of a cross

Answer 1

Mendel proposed that the factor controlling any character is discrete and independent. His proposition was based on the observations that the offspring of a cross made between the plants having two contrasting characters shows only one character without any blending.

Explanation:

Mendel proposed that the factors (genes) controlling any character are discrete and independent based on his observations that when he crossed plants with two contrasting characters (such as tall and dwarf), the first generation (F₁) offspring exhibited only one of the parental traits without any blending. This disproved the blending inheritance theory. Later, in the F₂ generation, both traits appeared in a predictable ratio, showing that the factors segregate and remain discrete. Thus, Mendel concluded that hereditary factors are discrete units that do not blend but independently assort during gamete formation. This fundamental discovery came from observation at the F₁ generation and subsequent generations confirming segregation and independent assortment of these discrete factors.