The cell nucleus is one of the largest organelles found in cells and also plays an important biological role. It composes about 10% of the total volume of the cell and is found near the center of eukaryotic cells. Its importance lies in its function as a storage site for DNA, our genetic material.
A monorail is a railway in which the track consists of a single rail. The term is also used to describe the beam of the system, or the vehicles traveling on such a beam or track.
rail noun (TRAINS) 1  B1 [ U ] the system of transport that uses trains: âº [ 2  C ] one of the two metal bars attached to the ground on which trains travel: 3  C2 [ C ] a horizontal bar fixed in position, especially to a wall or to vertical posts, used to close something off, as a support, or to hang things on: âº  to complain angrily: