Which chromosomal defect is caused when part of a chromosome breaks off and reattaches backward on the same chromosome?
1. inversion
2. translocation
3. deletion
4. insertion

The right answer is inversion.

Inversion is a genetic mutation characterized by the end-to-end reversal of a portion of chromatid on a chromosome.

In other words, it is a double break then it is replaced after rotation of 180 ° of a chromosome segment (backward insertion).

We distinguish :

Paracentric inversions:  The centromere in the chromosome is not included in the inversion.

Pericentric inversions:  The centromere is included in the inversion which transforms a metacentric chromosome into an acrocentric chromosome.

the element that provides strength to the exoskeletons of clams and oysters is phosphorus. this is so because calcium carbonate is the main component in the shells.

explanation:

eukarya because is is like alche and b is bacteria and d is animals

explanation: