Question

How many of the following statements are wrong?
Statement I: Strength of linkage is directly proportional to the recombination of genes.
Statement II: Recombination of genes is inversely proportional to the strength of linkage.
Statement III: More the distance between the two genes on a
chromosome, less will be the strength of linkage.
Statement IV: More the distance between the two genes on a
chromosome, more the strength of linkage.
Statement V: Recombination frequency is inversely proportional to the distance between the genes present on a chromosome.

• A. Three
• B. Four
• C. Two
• D. One

Answer 1

The correct option is A Three

Statements I, IV and V are incorrect and statements II and III are correct.

If genes are placed very close to each other on the same chromosome, chances of crossing over are very low. This lowers the chances of recombination. Hence, the strength of linkage would be more.

Linkage is the phenomenon of physical association of the genes in which genes are present so close that they do not get separated during meiosis and get inherited together as a unit. Linked genes can, however, get separated from each other sometimes, by an event called crossing over, if they are placed sufficiently far from each other.

Crossing over is the process of the exchange of segments of non-sister chromatids of homologous chromosomes. This occurs at the pachytene stage of meiosis during gamete formation. This leads to the generation of new combinations of genes, the process called recombination.