Hello Rittika...

Here is your ANSWER...
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TONGUE -

It is a fleshy organ found in oral cavity. It is attached to the floor of the mouth by a fold called the Lingual frenulum. There is an inverted V - shaped furrow called as Sulcus terminalis which DEVIDES upper surface of tongue into anterior oral part and posterior pharyngeal part.

The upper surface of tongue contains four types of little projections known as Papillae.
These papillaes are -

(i) Vallate Papillae or Curcumvallate papillae - These are the largest papillae and about 8 - 12 in number. Each papilla contain upto 100 taste buds.

(ii) Filliform papillae - these are the smallest and highest in number. These papillae contain tacticle (touch) receptors but don't have any taste buds.

(iii) Fungiform papillae - these are less in number. they are most numerous near the tip of tongue. one Fungiform papillae contains five taste buds.

(iv) Foliate papillae - These are not developed in HUMANS. These are leaf-like and situated at the sides of the base of tongue. Their taste buds degenerate in early childhood.

Human tongue has four types of taste areas - sweet, salt, SOUR and butter.

FUNCTION -

✓ It acts as accessory digestive organ.
✓ It helps in CHEWING the food.
✓ It helps in swallowing the food.
✓ It plays an important role in speech.
✓ It helps in recognition of taste.
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hope it will help you...
best of luck...