Rhinoceros is primarily a free form surface modeler that utilizes the NURBS mathematical model. Rhinoceros' application architecture and open SDK makes it modular and enables the user to customize the interface and create custom commands and menus.
Noun. 1. exigency-a pressing or urgent situation; the health-care exigency. crisis-an unstable situation of extreme danger or difficulty; they went bankrupt during the economic crisis.
Excretion is the process by which metabolic wastes and other non-useful materials are eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys and skin.[1] This is in contrast with secretion, where the substance may have specific tasks after leaving the cell. Excretion is an essential process in all forms of life. For example, in mammals urine is expelled through the urethra, which is part of the excretory system. In unicellular organisms, waste products are discharged directly through the surface of the cell. Green plants produce carbon dioxide and water as respiratory products.