1. The Head and Neck

2. Upper Respiratory Tract
Nostril
Nasal Cavity
Oral Cavity
Pharynx
pg 944

3. Nasal Cavity
pg 973
Nose is the only portion of the RT that is externally visible
CT, bone, hyaline cartilage
Functions:
Provides airway for respiration
Moistens and warms air
Filters inhaled air
Resonating chamber for speech
Houses olfactory receptors
2 divisions:
External nose
Internal nasal cavity

4. Nasal Cavity Air enters here during breathing
pg 944
Air enters here during breathing
Passes through the external nares (nostrils)
Divided into R and L by nasal septum
Continuous with the nasopharynx through the internal nares (choanae)

5. Nasal Cavity Boundries: Hard palate Soft palate
Roof – ethmoid bone (cribiform plate)
Floor – maxilla (palatine process)
palatine (horizontal plate)
Lateral walls – nasal bones, superior and middle nasal conchae of ethmoid bone, inferior nasal conchae, maxilla, palatine bone
Hard palate
Palatine bones and maxillary bone
Soft palate
Skeletal muscle posterior portion
End in uvula

6. Nasal Cavity Vestibule Vibrissae Superior to nostrils Skin lined with:
pg 965
Vestibule
Superior to nostrils
Skin lined with:
Sebaceous glands
Greasy secretion
Collect dirt
Lubricate
Kill bacteria
Sweat glands
Acidic
Slows growth of bacteria
Hair follicles
Trap small particles of dirt
Vibrissae
Nose hairs
Filter large particles (insects)

7. Lining of the Nasal Cavity
Olfactory Mucosa
Roof of nasal cavity
Houses smell receptors
Respiratory Mucosa
Pseudostratified ciliated columnar epithelium
Goblet cells
Lamina propria
Mucous and serous cells
Venous plexus
Function is to filter and warm inhaled air
Highly innervated
Sneeze!

8. Nasal Conchae Project medially from each lateral wall 3 structures:
pg 973
Project medially from each lateral wall
3 structures:
Superior of ethmoid bone
Middle of ethmoid bone
Inferior
Functions:
Create turbulence to increase:
Filters air
Heats air
Moistens air
Reclaim heat and moisture during exhalation

9. Paranasal Sinuses Air filled cavities that surround the nasal cavity
pg 970
Air filled cavities that surround the nasal cavity
Lined by mucosa
Perform same function as nasal cavity and lightens skull
Located in Frontal, Ethmoid, Sphenoid, Maxilla bones

10. Pharynx Connects the nasal cavity and mouth to larynx and esophagus
pg 944
Connects the nasal cavity and mouth to larynx and esophagus
Extends from base of skull to level of C6 vertebra
Common passage for food and air
Lined with skeletal muscle
Divided into:
Nasopharynx
Oropharynx
Laryngopharynx

11. Tonsils Lymphoid organ Swellings of the mucosa lining the pharynx
pg 944
Lymphoid organ
MALT
Swellings of the mucosa lining the pharynx
Form ring around the entrance to the pharynx
4 groups:
Palatine
Lingual
Pharyngeal
Tubal
Remove pathogens

12. Nasopharynx Location: ONLY an air passageway
pg 944
Location:
Posterior to nasal cavity
Inferior to sphenoid bone
Superior to level of soft palate
ONLY an air passageway
Closed off during swallowing by the soft palates’ uvula
Giggling!
Ciliated pseudostratified epithelium
Contain:
Pharyngeal tonsils (adenoids)
Tubal tonsils

13. Oropharynx Location: Swallowed food and inhaled air pass through here
pg 944
Location:
Posterior to the oral cavity
Extends inferiorly from level of the soft palate to level of the epiglottis
Swallowed food and inhaled air pass through here
Stratified squamous epithelium
Contain:
Palatine tonsils
Lingual tonsils

14. Laryngopharynx Location: Common passageway for food and air
pg 944
Location:
Lies posterior to larynx
Continuous with the esophagus and larynx
Common passageway for food and air
Food – esophagus
Air - larynx
Stratified squamous epithelium

15. Larynx “Voice box” Extends from C4 to C6 Attachments:
pg 949
“Voice box”
Extends from C4 to C6
Attachments:
Hyoid bone superiorly
Continuous with trachea inferiorly
Functions:
Vocalization
Provides open airway
Switches to route air and food into proper channels
Innervation: Vagus
Superior part = stratified squamous epithelium
Below vocal cords= ciliated pseudostratified columnar

16. Larynx All hyaline cartilage except epiglottis
pg 952-3
All hyaline cartilage except epiglottis
Composed of 9 cartilages connected by membranes and ligaments:
1 Thyroid
1 Cricoid
1 Epiglottis
2 Arytenoid
2 Corniculate
2 Cuneiform

17. Laryngeal Cartilages Thyroid Cartilage Large Shield shaped
pg 950
Thyroid Cartilage
Large
Shield shaped
Formed by 2 plates
Contains laryngeal prominence
Adam’s Apple!!

18. Laryngeal Cartilages Cricoid Inferior to thyroid cartilage
pg 952
Cricoid
Inferior to thyroid cartilage
Forms a complete ring
Directly superior to trachea

19. Laryngeal Cartilages Epiglottis Composed of elastic cartilage
pg 951
Epiglottis
Composed of elastic cartilage
Covered by mucosa
Projects upward from anterior wall of laryngeal inlet to level of base of tongue
Close off larynx during swallowing

20. Vocal Cords Located in the larynx
pg 960
Located in the larynx
Mucosal folds formed by vocal ligaments
Composed of elastic fibers
Run from arytenoid cartilages to the thyroid cartilages
Exhaled air passes over them and causes vibration
Force of air = volume
Length & tension of folds = pitch
False vocal cords
Vestibular folds (superior to true)

21. Thyroid Gland Location: 2 lateral lobes
pg 917
Location:
In anterior neck
On trachea, inferior to larynx
2 lateral lobes
Connected by the isthmus
Butterfly shape
Largest endocrine gland in body
Produces Thyroid hormone (TH)
Increases metabolic rate
Calcitonin
Depresses excess levels of Ca+ in blood

22. Thyroid Gland Internally, composed of follicles Blood supply
Follicular cells TH
Parafollicular cells
Calcitonin
Blood supply
Superior thyroid arteries
Branches of external carotids
Inferior thyroid arteries
Branches of subclavians

23. Parathyroid Gland Two pairs
pg 917
Two pairs
Located on the deep surface of the lateral lobes of the thyroid gland
Produce parathyroid hormone
Increases blood calcium levels

24. Hyoid Bone Location: Associated with the skull
pg 755
Location:
Inferior to mandible
In anterior neck
Associated with the skull
Only bone in skeleton that does not articulate directly to another bone!!!
Attaches via ligaments to temporal bone, larynx
Composed of:
Body
2 pairs of horns
Functions:
Moveable base for tongue
Points of attachment for larynx and neck muscles
Sternohyoid, thyrohyoid,

25. Oral Cavity and Associated Organs
pg 944
Mouth
Tongue
Teeth
External Salivary glands

26. Mouth - Oral Cavity Food enters alimentary canal through here
pg 993
Food enters alimentary canal through here
Mucosa-lined
Thick stratified squamous epithelium, with keratinization in some areas
Boundaries:
Lips anteriorly
Cheeks laterally
Palate superiorly
Tongue inferiorly
Oropharynx posteriorly
Mouth divided into 2 parts:
Vestibule
Oral cavity proper

27. Mouth Lips (labia) and Cheeks Palate: forms the roof of the mouth
Keep food inside mouth during chewing
Composed of skeletal muscle surrounded by skin
Lips formed by orbicularis oris muscle
Cheeks; Muscles of Mastication (pg )
Temporalis & Masseter (elevate mandible, close mouth)
Buccinator (chewing)
Digastric (lower mandible against resistance, opens mouth)
Pterygoids (lateral movements)
Palate: forms the roof of the mouth
Soft palate (posterior) rises to close off nasopharynx during swallowing; made of skeletal muscle
Hard palate (anterior) provides surface for tongue to force food against during chewing

28. Tongue Functions Creates floor of mouth
pg 989
Functions
Grips and moves food between teeth
during chewing
Mixes food with saliva = BOLUS
Moves bolus down pharynx
Speech production
Houses taste buds (= gustation)
Creates floor of mouth
Attachments: hyoid, mandible, styloid process, soft palate
Made of Skeletal muscle with a CT septum
Intrinsic muscles (change shape; rolling)
Extrinsic muscles (movement; protrude, retract)
Motor = Hypoglossal (CN XII)
Sensory = Mandibular (CN V3), Facial (CN VII), Glossopharyngeal (CN IX)

29. Moving Bolus Swallowing voluntarily initiated (pharynx)
Peristalsis = propulsion
Involuntary
Alternate waves of contraction and relaxation of muscles in organ walls (e.g. esophagus)
Squeezes food from one organ to next
Some mixing

30. Salivary Glands Compound tubuloalveolar glands
pg 997
pg 820
Compound tubuloalveolar glands
Intrinsic salivary glands
In mucosa of tongue, palate, lips and cheeks
Keeps mouth moist at all times
Extrinsic salivary glands
Lie external to mouth
Connected by ducts
Secrete only during eating or prior to (“mouth watering”)
3 paired glands:
Parotid
Submandibular
sublingual

31. Salivary Glands Produce saliva
pg 998
Produce saliva
Mixture of water, ions, mucus and enzymes
Moistens mouth
Dissolves food for taste
Binds food into a bolus
Enzymes digest starch
Bicarbonate buffer neutralizes acids
Kill microorganisms
Contains proteins to promote growth of beneficial bacteria

32. Teeth – From Eruption to Edentate
pg 1008
Teeth – From Eruption to Edentate
Function:
Ingestion and mechanical breakdown of food
Have 2 sets of teeth (dentitions)
Primary dentition / deciduous (milk) teeth
Permanent dentition
Incisors: rip, cut
Canines: tear and pierce
Premolars: grinding
Molars: grinding

33. Teeth
Gomphosis
Synarthrosis
Peg in socket with ligament
The sockets (alveoli) are in gum-covered margins of mandible and maxilla
Periodontal ligaments (collagen fibers) anchor tooth in bony socket
Continous with gingiva (gum)

34. Teeth Pulp cavity Regions: Center of tooth
Loose CT with vessels and nerves
Supplies nutrients to hard tissues
Regions:
Crown
Covered with enamel
Area projecting beyond gingiva
Neck (gumline)
Root
Area beyond neck in alveolus

35. Teeth Root Canal Apical foramen Blood supply Innervation
Portion of the pulp cavity in the root
Apical foramen
Opening into the root canal at the tip of each root
Blood supply
Superior/Inferior Alveolar artery, branches of External Carotid artery
Innervation
Maxilla = Superior Alveolar Nerves
Mandible = Inferior Alveolar Nerves

36. Teeth Substances Enamel Dentin Cementum Made of calcium salts
Avascular, acellular
Not renewed or replaced
HARDEST substance in body!!!!
Dentin
Underlines enamel
Forms bulk of tooth
Made of minerals and collagen
Maintained during life
Harder than bone
Cementum
Calcified external surface
Attaches tooth to periodontal ligament

37. Teeth at Birth Number of erupted teeth = 0
Jaws covered by gingiva (gums)
Lots of drooling!!!

38. First Teeth – 6 Months Lower central incisors first to appear
8 Incisors = 6-10 months
4 Canines = months
4 1st Molars = months
4 2nd Molars = months
20 deciduous teeth emerge by age 2
Dental formula
Describes the number and position of classes of teeth (half of the mouth)
2I, 1C, 2M
Deciduous teeth dental formula:
X 2 = 20
****No premolars!

39. Adolescence – Adult Permanent teeth enlarge and develop
pg 1008
Permanent teeth enlarge and develop
Roots of deciduous teeth reabsorbed
Teeth loosen and fall out
Begin to erupt from 7-13 years of age
Third molars (wisdom teeth) emerge from years
May be absent!!
Adult dental formula:
2I, 1C, 2P, 3M
X 2 = 32

40. Tooth Troubles Cavities (caries)
Demineralization of enamel by bacteria
In severe cases, erodes the dentin of tooth
Most severe cases erosion penetrates pulp cavity

41. Tooth Troubles Gingivitis Periodontitis
Inflammation of the gingiva caused by plaque accumulation
Leads to…….
Periodontitis
Infection of periodontal ligament leading to its destruction along with the bone around the teeth
Leads to……………Toothlessness!

42. Triangles of the Neck Neck subdivided into two triangles
Separated by the sternocleidomastoid muscle
Anterior triangle
Posterior triangle

43. Triangles of the Neck: Posterior
pg 905
Boundries:
Anterior - sternocleidomastoid
Posterior - trapezius
Inferior – clavicle
Contents:
Nerves: accessory nerve, phrenic nerve, brachial plexus
Artery: Subclavian
Vein: External jugular

44. Triangles of the Neck: Anterior
pg 762
Boundries:
Anterior - midline
Posterior - sternocleidomastoid
Superior – inferior margin of the mandible
Contents:
Glands: Submandibular
Muscles: Suprahyoid and infrahyoid muscles
Artery: Common carotid
Vein: Internal jugular, External jugular
Nerve: Accessory