Final answer:
An acentric chromosome fragment lacks a centromere, making it unable to segregate properly during cell division. Telomerase maintains telomeres, which are repetitive sequences at the ends of chromosomes that protect genetic information.
Step-by-step explanation:
A piece of a chromosome that has lost its centromere is called a acentric fragment. The centromere is vital for the proper segregation of chromosomes because it is the region where the sister chromatids are held together and to which the spindle fibers attach during cell division. Without a centromere, a chromatid cannot be properly segregated to the daughter cells during cell division, leading to loss of genetic information.
The enzyme responsible for maintaining the ends of linear chromosomes, known as telomeres, is telomerase. Telomeres consist of repetitive noncoding sequences that protect the coding DNA from erosion through successive rounds of replication. In humans, telomeres have a repeat sequence of TTAGGG that is added to the ends of chromosomes by telomerase. This process ensures that the chromosomes do not lose vital genetic information each time the cell divides.