Question

In pericentric inversion, the inversion loop involves __________ strands.

(a) 1

(b) 2

(c) 3

(d) 4

The question was asked at a job interview.

My doubt stems from Chromosomal Abnormality : Inversion in portion Chromosomal Basis of Inheritance of Cytogenetics

Answer 1

Right option is (d) 4

The best I can explain: In pericentric inversion there will be 4 strands in the inversion loop although only 2 will undergo recombination to give the recombination products. This is because the sister chromatids are bound by the centromere.