Human beings have amultitude of senses. Sighthearing, taste, smell or andtouch are the fivetraditionally recognized.
Senses are physiologicalcapacities of organisms that providedata for perception. The senses andtheir operation, classification, andtheory are overlapping topics studiedby a variety of fields ,most notablyneuroscience, cognitive physiologyand philosophy of perception.
Aristotle (384 BC - 322 BC) iscredited with the traditionalclassification of the five sense organs.As far back as the 1760s, the famousphilosopher Immanuel Kantproposed that our knowledge of theoutside world depends on our modesof perception.
Sight, ability to see. The eye is theorgan of vision. It has a complexstructure consisting of a transparentlens that focuses light on the retina.The retina is covered with two basictypes of light-sensitive cells-rods andcones.
Smell The nose is the organresponsible for the sense of smell. Thecavity of the nose is lined with mucousmembranes that have smell receptorsconnected to the olfactory nerve.
The smell receptorsinteract with themolecules of these vaporsand transmit thesensations to the brain.
Hearing The ear is the organ of hearing. Theouter ear protrudes away from the head andis shaped like a cup to direct sounds towardthe tympanic membrane, which transmitsvibrations to the inner ear through a series ofsmall bones in the middle ear calledthe malleus, incus and stapes.
Touch. The sense of touch is distributedthroughout the body. Nerve endings in theskin and other parts of the body transmitsensations to the brain. Four kinds of touchsensations can be identified: cold, heat,contact, and pain. Hairs on the skin magnifythe sensitivity and act as an early warningsystem for the body.
Taste. The receptors for taste, called tastebuds, are situated chiefly in the tongue,but they are also located in the roof of themouth and near the pharynx. They are ableto detect four basic tastes: salty, sweet,bitter, and sour. The tongue also can detecta sensation called "umami" from tastereceptors sensitive to amino acids.
Umami, a savory taste,is one of the five basictastes, together withsweet, sour, bitterand salty.
Perception (from theLatin perceptio, percipio) is theorganization, identification andinterpretation of sensoryinformation in order to representand understand the environment.