Which of the following was NOT a character studied by Mendel in his experiments with Pisum sativum?

Question

Which of the following was NOT a character studied by Mendel in his experiments with Pisum sativum?

1. A. Stem Height
2. B. Flower shape (Correct answer)
3. C. Pod shape and colour
4. D. Seed shape and colour

Correct Answer

Option B — Flower shape

Detailed Solution & Explanation

The correct answer is Flower shape.

Key Points

• Gregor Johann Mendel studied seven pairs of contrasting characters in the garden pea, *Pisum sativum*. Flower shape was not among them — he studied flower colour and flower position, but never flower shape.
• The seven characters Mendel actually studied:

Additional Information

• Why Mendel chose the garden pea:
  • It has clear contrasting traits with no intermediates.
  • It is naturally self-pollinating, so pure lines are easy to maintain, yet cross-pollination can be performed manually.
  • It has a short life cycle and produces many seeds per generation.
• Mendel's three laws:
  • Law of Dominance — in a heterozygote, only the dominant allele expresses itself.
  • Law of Segregation — the two alleles of a gene separate during gamete formation, so each gamete receives only one. This is the law of purity of gametes and has no exception.
  • Law of Independent Assortment — alleles of different genes assort independently, valid only for genes on different chromosomes or far apart on the same one.
• Characteristic ratios: monohybrid cross gives 3:1 phenotypic and 1:2:1 genotypic; dihybrid cross gives 9:3:3:1.
• Mendel published his work in 1866, but it was ignored until rediscovered independently in 1900 by de Vries, Correns and Tschermak.