AP BIOLOGY

Detailed explanation-1: -Duplications. Duplications occur when part of a chromosome is abnormally copied (duplicated). This type of chromosomal change results in extra copies of genetic material from the duplicated segment.

Detailed explanation-2: -One example of a rare genetic disorder of duplication is called Pallister Killian syndrome, where part of the #12 chromosome is duplicated.

Detailed explanation-3: -The four main types of structural chromosomal aberrations are deletion, duplication, inversion, and translocation.

Detailed explanation-4: -Duplication/Amplifications. As the name implies, an extra copy of a segment or the entire chromosome is present in the nucleus. These are also known as partial trisomies. Often an organism that usually has two copies of a chromosome will have three in the case of duplication.

Detailed explanation-5: -There are two types of duplication: 1. Direct: segment of chromosome is repeated, once or several times, the duplicated segment keeping the same orientation with respect to the centromere ("tandem duplication") and 2. Inverted: the duplicated segment takes the opposite orientation (1, 2).