Question

Inversions are classified into two types. In a(n) .................. inversion, the centromere lies within the inverted region of the chromosome, while in a(n) ....................... inversion, the centromere is located outside the inverted region.

Answer 1

Chromosomal inversions are classified into pericentric inversions, where the centromere is included within the inverted region, and paracentric inversions, where the centromere lies outside. Pericentric inversions can alter the chromosome arms' lengths, while paracentric inversions cannot. These types are observed during meiosis to maintain gene alignment.

Step-by-step explanation:

Inversions are a type of chromosomal rearrangement that are classified into two types based on the position of the centromere. In a pericentric inversion, the centromere lies within the inverted region of the chromosome. In contrast, in a paracentric inversion, the centromere is located outside the inverted region of the chromosome. A pericentric inversion that is asymmetric about the centromere can change the relative lengths of the chromosome arms, making such inversions easily identifiable. Paracentric inversions do not change the arms' relative lengths. Understanding these types of chromosomal inversions is critical for interpreting cytogenetic data, particularly when observing cells during meiosis as homologous chromosomes must contort to maintain gene alignment.