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

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

3. Nose/Nasal Cavity and Breathing
Function:
Inlet for air to lung
Warm/filter air
(mucous membranes on ethmoid conchae)
Smell
(nerve endings on nasal membranes)

4. Conchae of Ethmoid Bone
Scroll-like bones
Covered in mucous membrane for
Smell
Filter air
Warm air

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

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

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)
Lips

8. Cheeks FUNCTION Form side of moth STRUCTURE
Buccinator muscle— instrumental in swallowing, connects back to pharyngeal constrictors

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…???

10. Jaws FUNCTION Hold teeth Occlude in chewing STRUCTURE
Upper jaw—maxillary bone
Lower jaw--mandible

11. Teeth Key to healthy teeth and gums: Flossing
Deciduous teeth—”milk” or “baby” teeth
Emerge 6 mos. – 2 yrs.
Replaced by permanent teeth 6-12 yrs.
Wisdom teeth (3rd molar) erupts 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.)

12. Structure of individual tooth—it’s alive!!

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

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

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

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

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

18. Pharynx and Swallowing
Focus on muscles and arrangement of mouth cavity, pharynx, larynx, epiglottis, trachea
Pharynx/Swallowing in detail!!

19. Descent of the 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

21. Skeleton of larynx
M&M, Fig. 21.5
Cricothyroid ligament is usual site of emergency tracheotomy (feel on self—SURFACE ANATOMY)

22. Vocal cords
M&M, Fig. 21.6