Statement I: Gregor Mendel conducted hybridisation experiments on garden peas for seven years (1856-1863).
Statement II: Mendel selected 14 true-breeding pea plant varieties, as pairs which were similar except for one character with contrasting traits.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Both statements I and II are correct.
Mendel worked with the garden pea. He used true-breeding lines: lines that, after continuous self-pollination, show the same trait generation after generation.
Statement I: Gregor Mendel conducted hybridisation experiments on garden peas for seven years (1856-1863). — True. Mendel crossed (hybridised) pea plants for seven years, from 1856 to 1863, and from them proposed the laws of inheritance.
Statement II: Mendel selected 14 true-breeding pea plant varieties, as pairs which were similar except for one character with contrasting traits. — True. The 14 varieties form 7 pairs. The two plants of a pair differed in one character only, for example tall or dwarf plants, or round or wrinkled seeds.
NCERT Extract:
Mendel’s Laws of Inheritance – “It was during the mid-nineteenth century that headway was made in the understanding of inheritance. Gregor Mendel, conducted hybridisation experiments on garden peas for seven years (1856-1863) and proposed the laws of inheritance in living organisms. … A true-breeding line is one that, having undergone continuous self-pollination, shows the stable trait inheritance and expression for several generations. Mendel selected 14 true-breeding pea plant varieties, as pairs which were similar except for one character with contrasting traits.”