SENSORY ORGANS ANATOMY. 1  Sensory organs are very highly developed and specialized organs that are an extension of the central nervous system, with a sole function to take in information and relate it to the brain. The sensory neurons are highly adapted to detect changes of both external and internal changes in the environment and report these changes to the brain.
If you break a mercury thermometer or light bulb, a small amount of liquid mercury may spill out. Liquid mercury can separate into small beads, which can roll some distance away. The mercury may also evaporate into vapour. However, this small amount of mercury is extremely unlikely to cause problems for your health.
As shown in the picture of the aneroid barometer, this instrument relies on a sealed, flexible unit which contains air at a fixed volume. As the atmospheric air pressure changes, this membrane expands and contracts, altering the position of a needle on the barometer. Mercury barometers use an evacuated tube, and Mercury rises or falls within this tube as the atmospheric pressure changes, pushing the Mercury higher or lower in the tube.