instruction:
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.
question:
Lin and Shu proposed the density-wave theory to explain how the structure of these entities is sustained. The most accurate method for measuring the distances to distant ones uses a relation between their maximum rotational velocity and absolute magnitude, which is known as the Tully-Fisher method. They are generally blue because of their high content of old stars, and one type of them features arms that emanate from each end of a namesake structure. They have discs like the lenticular type, but contain much more angular momentum than the elliptical type. FTP name these galaxies, some of which are barred, including the Milky Way.
answer:
Science


question:
Imetelstat, a potential new cancer therapy agent, works by targeting the enzyme that repairs these   structures. Blackburn, Greider, and Szostak received the 2009 Nobel Prize for determining the role of  these structures, which typically adopt a G-quadruplex shape. The shortening of these structures   explains the Hayflick limit to cell division and is the basis for the cellular theory of aging, and that  shortening of these structures can lead to cell senescence or apoptosis. Consisting of thousands of  TTAGGG repeats in humans, name these end sequences of chromosomes that prevent genes from  being lost during DNA replication.
answer:
Science


question:
The Abbe number is defined in terms of this quantity, which can be found using Cauchy's or Sellmeier's equation. It is equal to the square root of the product of the relative permeability and the relative permittivity of the material, and metamaterials could have a negative value for this quantity. The arctangent of the ratio between two materials' values for this gives Brewster's Angle. It also appears in an equation that follows from Fermat's Principle, Snell's Law, and it is defined as the ratio of the speed of light in a vacuum to in a medium. For 10 points, name this property which governs a namesake effect in which a beam of light is bent as it passes between mediums.
answer:

Science