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.
subway. 1  Also called, especially British, tube, underground. an underground electric railroad, usually in a large city. 2  Chiefly British. a short tunnel or underground passageway for pedestrians, automobiles, etc.; underpass. 3  to be transported by a subway: We subwayed uptown.