Question

Deletions occur most often in chromosomal fragments

• A. of polytene chromosomes
• B. without centromeres
• C. with centromeres
• D. with inversions

Answer 1

The correct option is B without centromeres

When a chromosome is broken into several pieces, the reunion of the segments takes place by uniting together ends of the fragments, leaving one or more acentric parts free. The acentric pieces of chromosomes disappear. The healed segments will form a chromosome that will be deficient for some of the genes, particularly those found on the lost part. Therefore deletions occur in the acentric (regions without centromere) parts of the chromosome.

So, the correct answer is 'without centromeres'.