In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

In yeast, Pot1 has been found to be critical to their stability, and the malfunction of these structures can result in ataxia telangiectasia. SIR2, SIR3 and SIR4At the end of each one of these is a complex including TIN1, TIN2, and POT1 known as the shelterin complex and includes the T-loop, and when they are compromised, their namesake dysfunction-induced foci are created. In yeast, they are regulated by the Rap1 protein, while in humans, they are regulated by TRF1. The number of times a cell may divide before these become critical is the Hayflick limit, and they are distinguished from double-strand breaks by protecting against non-homologous end joining in the "capping" process. For 10 points, name these sequences, which in vertebrates are repetitions of TTAGGG, that protect the ends of chromosomes from destruction during replication.
Science