We can taste substances in food and drink thanks to the 10,000 or so taste buds located on structures, called papillae, on the surface of our tongues. These receptors send signals along nerves to the brain for interpretation. Four main tastes – sweet, salty, sour, and bitter – are detected by the taste buds in four areas of the tongue. The senses of taste and smell combine to analyse flavours.
Papillae are tiny protrusions on the surface of the tongue. The fungiform papillae and some other types of papillae contain taste buds. The smaller, more numerous, filiform papillae do not contain taste buds but give the tongue a rough surface, which helps it move food around the mouth.
Hairs emerge from each receptor cell. Food and drink molecules must dissolve in saliva before they can interact with these hairs and trigger signals to the brain.
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