Which chromosomal defect is caused when part of a chromosome breaks off and reattaches backward on the same chromosome?

Translocation

Explanation:

Translocation is a chromosomal defect in which part of a chromosome breaks off and reattaches backward on the same chromosome.

Translocation can happen due to many reasons like:

A) Some of the changes that arise around the time of conception  or production of sperm or egg.

B) The inheritance of altered chromosome from father or mother.

Translocations can be divided into two forms:

In reciprocal translocations,  fragments of two chromosomes break off from two different places, break and swap each other's segments. While in  Robertsonian translocation one chromosome attached with other.

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•there must be variation for the particular trait within a population.

•the variation must be inheritable (that is, it must be capable of being passed on from the parents to their offspring).

•individuals with one version of the trait must produce more offspring than those with a different version of the trait.good

explanation: