HEAD/NECK II: Throat/ Pharynx

1. HEAD/NECK II: Throat/ Pharynx • Overview: Sagittal view of nose/mouth/throat • Nasal Cavity and Breathing • Mouth and Chewing • Throat and Swallowing • Larynx and Singing Human Anatomy, Frolich, Head II: Throat/Larynx

2. Sagittal Section Head • Cranial cavity • Brain/Spinal cord • Vertebral bodies • Epaxial muscles • Hard/soft palate • Oral cavity • Esophagus • Trachea • Epiglottis • Naso- • Oro- • Laringo- pharynx Human Anatomy, Frolich, Head II: Throat/Larynx

3. Nose/Nasal Cavity and Breathing Function: • Inlet for air to lung • Warm/filter air (mucous membranes on ethmoidconchae) • Smell (nerve endings on nasal membranes) Human Anatomy, Frolich, Head II: Throat/Larynx

4. Conchae of Ethmoid Bone • Scroll-like bones • Covered in mucous membrane for • Smell • Filter air • Warm air Human Anatomy, Frolich, Head II: Throat/Larynx

5. Sinuses • All connected to nasal cavity • All lined with mucous membranes • Cold/allergies—fill with mucous=sinus headache • Maxillary • Ethmoid • Frontal • Sphenoid M&M, Fig. 7.11 Human Anatomy, Frolich, Head II: Throat/Larynx

6. Mouth/Oral Cavity and Chewing • FUNCTION • Bite and chew food • Form words • Taste • Kiss COMPONENTS • Lips • Cheeks • Palate • Jaws and teeth • Salivary glands Lined by thick stratified squamous epithelium (almost no keratin) Vestibule—in front of teeth Oral cavity proper—behind teeth Human Anatomy, Frolich, Head II: Throat/Larynx

7. Lips FUNCTION • Close mouth • Keep food in • Make speech sounds • Tactile STRUCTURE • Core of sphinchter-shape skeletal muscle (orbicularis oris) • “Red margin” transition from keratinized skin to oral mucosa • Red because clear color lets underlying vessels show through • No sweat or sebaceous glands, thus needs to be wet (or lip balm) Human Anatomy, Frolich, Head II: Throat/Larynx

8. Cheeks FUNCTION • Form side of moth STRUCTURE • Buccinator muscle—instrumental in swallowing, connects back to pharyngeal constrictors Human Anatomy, Frolich, Head II: Throat/Larynx

9. Palate • Hard palate anterior • Maxilla • Palatine • Soft palate is posterior extension, soft tissue • Palatoglossal arch (palate to tongue) • Palatopharyngeal arch (palate to pharynx) • Tonsils between arches • Uvula…??? Human Anatomy, Frolich, Head II: Throat/Larynx

10. Jaws FUNCTION • Hold teeth • Occlude in chewing • STRUCTURE • Upper jaw—maxillary bone • Lower jaw--mandible Human Anatomy, Frolich, Head II: Throat/Larynx

11. Teeth • Deciduous teeth—”milk” or “baby” teeth • Emerge 6 mos. – 2 yrs. • Replaced by permanent teeth 6-12 yrs. • Wisdom teeth (3rd molar) erupts 17-25 yrs or remains in jaw • Key to healthy teeth and gums: • Flossing • Visiting dentist regularly (every 6 mos.) and starting at young age (3-4 yrs.) Human Anatomy, Frolich, Head II: Throat/Larynx

12. Structure of individual tooth—it’s alive!! Human Anatomy, Frolich, Head II: Throat/Larynx

13. Jaw muscles • Masseter, temporalis—elevate mandible (“close jaw”) • Medial pterygoid—lateral (side-to-side) chewing • Lateral pterygoid—translates mandible anteriorly (part of opening) • Digastric (not shown)—depresses mandible (“opens jaw”) • Chewing is circular motion Human Anatomy, Frolich, Head II: Throat/Larynx

14. Tongue FUNCTION • Position food between teeth • Form words in speech STRUCTURE • Intrinsic muscles (allow for shape change with fibers in various directions) • Extrinsic muscles—attach tongue to skeleton • Genioglossus • Hyoglossus Human Anatomy, Frolich, Head II: Throat/Larynx

15. Salivary glands • Intrinsic—all over mucous membranes of tongue, palate, lips, lining of cheek • Extrinsic—secrete more saliva when eating (or anticipating) • Parotid • Submandibular • Sublingual Human Anatomy, Frolich, Head II: Throat/Larynx

16. Saliva • Moistens mouth • Dissolves food to be tasted • Wets and binds food • Contains amylase to start starch digestion (saltine to sugar experiment) • Contains bicarbonate to neutralize cavity-causing acids produced by bacteria • Contains anti-bacterial and anti-viral enzymes and cyanide-like compound to kill harmful micro-organisms • Contains proteins that stimulate growth of beneficial bacteria in the mouth Human Anatomy, Frolich, Head II: Throat/Larynx

17. Air Food PHARYNX Trachea Esophagus Throat/Pharynx and Swallowing • Back of mouth to larynx • Food and air mix and cross • STRUCTURES • Entry—pharyngeal arches • Exit—glottis (epiglottis is lid) • Pharyngeal constrictors squeeze food through • When it goes wrong—choking!! Human Anatomy, Frolich, Head II: Throat/Larynx

18. Pharynx and Swallowing Focus on muscles and arrangement of mouth cavity, pharynx, larynx, epiglottis, trachea Pharynx/Swallowing in detail!! Human Anatomy, Frolich, Head II: Throat/Larynx

19. Descent of the larynx Human Anatomy, Frolich, Head II: Throat/Larynx

20. Larynx and Singing FUNCTION • Channel air out of trachea • Vibrate to produce sound for speech/song STRUCTURES • External skeleton or frame (cartilage) • Internal vocal cords and associated muscles Human Anatomy, Frolich, Head II: Throat/Larynx

21. Skeleton of larynx • Cricothyroid ligament is usual site of emergency tracheotomy (feel on self—SURFACE ANATOMY) M&M, Fig. 21.5 Human Anatomy, Frolich, Head II: Throat/Larynx

22. Vocal cords M&M, Fig. 21.6 Human Anatomy, Frolich, Head II: Throat/Larynx