1. The process of separating the nitrogenous waste from the blood with the help of a manmade machine is called dialysis.
2. An immediate and involuntary response given to a stimulus from the environment is called a reflex action.
3. Proper co-ordination between various systems of an organism helps to maintain a state of equilibrium called homeostasis.
4. Movement or growth of any part of the plant in response to an external stimulus is called tropism.
