In biological organisms, increased temperature results in a fever which serves as a signal that there is something wrong with the organism. In buildings, different kinds of sensors and their associated alarms have a similar purpose. For example, smoke detector will trigger a fire alarm if temperature in the building increases above a certain level. Electrical wiring in buildings is an important part of building systems that lets different parts of a building communicate with each other. Similarly, in organisms electrical impulses are sent through the nervous system. In buildings, when a part of the plumbing system is clogged, there is likely to be flooding. In organisms, clogged veins and arteries can lead to dangerous events such as heart attacks.