MUSCLES OF TONGUE

• DIVIDED INTO TWO TYPES OF MUSCLES- EXTRINSIC & INTRINSIC
• EXTRINSIC MUSCLES - 

1. GENIOGLOSSUS- origin: Genial tubercle of mandible; insertion: Tip and dorsum of tongue & hyoid bone.
2. HYOGLOSSUS-origin: Greater cornua of hyoid bone; insertion: Side of tongue 
3. STYLOGLOSSUS- origin: styloid process; insertion: Side of tongue
4. PALATOGLOSSUS-origin: palatine aponeurosis; insertion: side of the tongue at the junction of tongue and pharynx.

• INTRINSIC MUSCLES-

1. SUPERIOR LONGITUDNAL
2. INFERIOR LONGITUDNAL
3. TRANSVERSE
4. VERTICAL

• NERVE SUPPLY OF TONGUE-

1. SENSORY NERVE SUPPLY- Lingual nerve branch of mandibular nerve(general nerve for sensation) & chorda tympani nerve branch of facial nerve(Taste sensation except circumvallate papillae) supply anterior two third of tongue.Glossopharyngeal nerve supplies sensory & taste  innervation to posterior one third of tongue including circumvallate papillae.Laryngeal branch of Vagus nerve supply most posterior part of tongue
2. MOTOR NERVE SUPPLY-Hypoglossal nerve to all muscles except palatoglossus which is supplied by cranial part of accessory nerve.

• PAPILLAE- A small, round or cone-shaped bump on the surface of the tongue. There are several types of papillae in the mouth, and all but one type containtaste buds.
  
  Fungiform - taste bud-containing papillae located on the front two-thirds of the tongue. They can be seen as red bumps (the bumps that stand out in contrast to the pinkness of the rest of your tongue); under magnification, they look a bit like mushrooms (fungi).
  Circumvallate - taste bud-containing papillae toward the very back of the tongue; they are placed in an inverted “V.” It can be very hard to see your own, but it is fairly easy to see these in another person, especially if you use a flashlight.
  Foliate - taste bud-containing papillae located very far back on the sides of the tongue; they look like a series of folds or lines and can be very difficult to see.
  Filiform - papillae that do not contain taste buds. They cover the surface of the tongue in great abundance and are largely responsible for the texture of the tongue. The only purpose it serves in tasting is that it can help to hold taste compounds on the tongue, increasing the chance that the taste compound will interact with a taste receptor cell.