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SENSE ORGANS

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                                       SENSE ORGANS Definition of  sense organ   A sense organ is defined as a group of specialized cells, tissues or receptors which is able to receive, perceive or detect stimulus and transmit information, impulse or message to the central nervous system. Sense organs are the bodily structure that receives a stimulus and is affected in such a manner as to initiate excitation of associated sensory nerve fibers which convey specific impulses to the central nervous system where they are interpreted as corresponding sensations                         TYPES OF SENSE ORGANS   There are five senses: sight, hearing, taste, smell and touch. There are organs connected with these sense that take in information that is sent to the brain so that the body can act on it. ...
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Gas welding

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WHAT IS GAS WELDING GAS welding is a m etal  joining  process  in which the ends of pieces to be joined are heated at their  interface  by producing coalescence with one or more gas flames (such as oxygen and acetylene), with or without the use of a filler metal. It can also be defined as a welding in which combination of gases , usually   oxyacetylene , is used to provide a   hot flame . Gas welding is a process that use fuel gases and oxygen to  weld  and cut metals, respectively. French engineers Edmond Fouché and Charles Picard became the first to develop oxygen- acetylene welding in 1903. Pure oxygen, instead of  air , is used to increase the  flame temperature  to allow localized melting of the workpiece material (e.g. steel) in a room environment. A common propane/air flame burns at about 2,250 K (1,980 °C; 3,590 °F), a propane/oxygen flame burns at about 2,526 K (2,253 °C; 4,087 °F...
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