Question

A chromosome has the following segments, where + represents the centromere: A B C + D E F G H What type of chromosomal aberration does the following chromosome have? A B C + D G F E H

Answer 1

Paracentric inversions

Step-by-step explanation:

Inversion is a type of mutation in which the chromosomal segment breaks and rearranges itself and rotates at an angle of about 180°.

Since the rotation is at 180° and the sequence is inverted therefore the mutation is known as the inversion. The inversion is of two types: pericentric (centromere is involved) and paracentric (centromere is not involved).

In the given question,

The normal sequence is A B C + D E F G H

The abnormal sequence is A B C + D G F E H

+ denotes the centromere.

Since the sequence D E F G H is reverse but has not involved the centromere, therefore, the inversion is paracentric.

Thus, paracentric inversion is correct.

Answer 2

Answer: A paracentric type of inversion

Step-by-step explanation:

Inversion occurs when a given segment of chromosome is excised and then reinserted at an orientation 180 degrees from the normal orientation. This paracentric type of inversion does not include the centromere.