MANUAL PHYSIOLOGY PRACTICAL - Repository:The Medical ...

FM/UOJ
Experiment 4
TESTS FOR CHEMICAL SENSES
Taste and smell are components of chemical senses. Even though the receptors,
their location, and the nervous connections are different for both sensations, perception of
both is interconnected and provides the flavor of the food. The sense of smell in humans
has apparently lost its importance in identification of substances for protection and sexual
function.
The aim of this practical is to demonstrate the senses of taste and smell, the ability
to identify substances by these senses. Also, the precautions to be taken to test these
sensory modalities to locate nerve lesions are highlighted.
Method:
A series of solutions of various substances are placed on one side of the lab. Get
one of your companions to deliver one drop of one solution on your tongue by means of
the dropper given. Record the taste modality (sweet, sour, salt, or bitter) and the substance
dissolved against its number. Wash the mouth thoroughly before testing the other
substance and go on to complete the series.
Another series of substances are placed on the other side. Close your eyes, take
the bottle near the nose and sniff gently. Identify the smell and note the name of the
substance against its number. Complete this series.
The identification can be corrected with the list available with the staff member.
Note:
Hot is not a taste modality as it stimulates the pain fibers and not the taste buds.
Ammonia, peppermint and other irritants also stimulate pain fibers in nasal cavity and
they do not stimulate sense of smell.
Exercise: list the causes of loss of these sensations:
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Neurology
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