Supported by. Pat Tillman walked away from a lucrative career in the National Football League to join the military and fight in Afghanistan, where he was ultimately killed by friendly fire in an incident that was initially covered up.
A membrane-enclosed sac that is part of the endomembrane system of a eukaryotic cell, having diverse functions. central vacuole. A membrane-enclosed sac occupying most of the interior of a mature plant cell, having diverse roles in reproduction, growth, and development. peroxisome. sac made of membrane in the cytoplasm of a eukaryotic cell. endoplasmic reticulum (ER). An extensive membranous network in a eukaryotic cell, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free (smooth) regions.
During cell division (mitosis), the centrosome divides and the two parts move to opposite sides of the dividing cell. The centriole is the dense center of the centrosome (plant cells do not have centrioles). Vacuole (animal) Fluid-filled, membrane-surrounded cavities inside a cell. The vacuole fills with food being digested and waste material that is on its way out of the cell. Vacuole (plant) A large, membrane-bound space within a plant cell that is filled with fluid.