After explaining open and cloak systems, ask for examples of open and closed systems. An example of an open system is household plumbing. Examples of closed systems include the refrigeration units of refrigerators and hot water heating systems in houses. The human circulatory system is a closed system. Demonstrate a faucet which is an example of a valve.
Valves regulate the flow of a liquid or gas.
Demonstrate other valves. Valves and Pumps A pump is a device for moving a liquid or gas from one place to another. Examples of valves include faucets, garden hose nozzles, and soap dispensers. McGill Virtual Stethoscope Project Go to this link to listen to the body with a virtual stethoscope. Learn about the Human Body Gallery .