Question

a. Why did Mendel choose pea plants for his experiments? Give any four reasons.
b. State Mendel’s law of independent assortment.

Answer 1

Hint: The hybridization experiments were conducted by Mendel on around 29,000 pea plants. He chose pea plants because they had easily observable traits. The Law of independent assortment states that the inheritance of one character is always independent of the inheritance of other characters within the same individual.

Complete Answer:
a. Mendel choose pea plants for his experiments because of the following reasons:

(i) The flowers of this plant are bisexual.
(ii) They are self-pollinating, and thus, self and cross-pollination can easily be performed.
(iii) The different physical characteristics were easy to recognize and study.
(iv) They have a shorter life span and are the plants that are easier to maintain.

b. According to Mendel's law of independent assortment, during the inheritance of two or more characters, the assortment of individual traits takes place independently during gamete formation.
- Thus, each allele of a pair segregates independently and each gamete formed contains one allele of that trait. This law is based on a hybrid cross.
- It can be simply said that if the inheritance of more than one character is studied simultaneously, the factors or genes for each character assort out independently to the other gene or factor.
- The Law of independent assortment can be understood by a simple example of the Mendelian dihybrid cross.
- When yellow round and green wrinkled pea plants were crossed, the presence of new combinations was observed i.e., round green and wrinkled yellow. This suggests that the genes for the shape of the seed and color of the seed are assorted independently.

Note: The law of independent assortment is not applicable to linked genes. The other two laws of Mendel are,
(I) Law of dominance
(II) Law of segregation