Sludge treatment, reuse and disposal. Sludge is produced from the treatment of wastewater in on-site (e.g. septic tank) and off-site (e.g. activated sludge) systems. This is inherently so because a primary aim of wastewater treatment is removing solids from the wastewater.
The central vacuole is a cellular organelle found in plant cells. It is often the largest organelle in the cell. It is surrounded by a membrane and functions to hold materials and wastes. It also functions to maintain the proper pressure within the plant cells to provide structure and support for the growing plant.
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.