Question

Write a short paragraph explaining the chromosome theory of inheritance. Be sure to explain Mendel’s Law of Segregation and Mendel’s Law of Independent Assortment.

Answer 1

The chromosomal theory of inheritance was given by Sutton and Boveri. It suggests that genes are present on specific loci on the chromosomes, which are present as homologous pairs in an individual. A homologous pair represents two chromosomes, one of which is inherited from the father, and the other inherited from the mother. These chromosomes behave in a certain way during meiosis, which explains the Mendel's law of segregation and the law of independent assortment.

Mendel, through his law of segregation suggested that, the two alleles for a given trait separate during the formation of gametes. According to the chromosomal theory of inheritance, the separation of alleles takes place through the separation of chromosomes, present in a homologous pair. Separated alleles are then passed into different gametes.

The separation of different chromosomes of a homologous pair, occur independently of each other. This explains Mendel's law of independent assortment, which suggests that alleles of a given trait separate independently of each other during gamete formation. This results in the formation of gametes, with different allelic combinations.

A diagram describing the chromosomal theory of inheritance has been given below-

Thus, at the end, four different types of gametes are produced.