biological cycle(A series of transformations or biological events which follow one after the other one, reaching at the end of the cycle the initial conditions, as in the life cycle of many animal and plant organisms)
biological effect(Biological effects include allergic reactions, respiratory disorders, hypersensitivity diseases and infectious diseases and can be caused by a variety of contaminants and pollutants)
biological engineering(The application of engineering principles and techniques to living organisms. It is largely concerned with the design of replacement body parts, such as limbs, heart valves, etc.)