Lecture 14 URT Flashcards
What is the main role of the Respiratory System?
Provide air for gas exchange
what must the Surface for gas exchange be?
– Air and blood close but separate (thin)
– Safe location (deep in body - thorax) - protect by ribs and vertebral column
- large SA
what must the air be for gas exchange?
optimal condition for gas exchange
• Warm, clean, moist
what else does the respiratory system do?
Produce sounds
Olfaction
whats the Conducting region?
nasal cavity to bronchioles
whats the Respiratory region?
Sites of gas exchange = alveoli
what does the Upper Respiratory Tract (URT) consists of?
– Nose & Nasal cavity
– Paranasal sinuses
– Pharynx (naso, oro, laryngo)
whats the function of URT?
Conducting passage (not only air)
- Prepares air for respiratory membrane (gas exchange)
- Paranasal sinuses - resonating chambers for speech
- Olfaction – sensory receptors smell
whats paranasal sinus?
resonating chambers for speech
whats Olfaction?
sensory receptors smell
A body system open to the environment is lined with
mucous membrane
Respiratory Tract
- Mucous membrane
Epithelium on layer of connective tissue (lamina propria)
Epithelium responds to function
Change along length of RS tract
what type of epithelium Lines chambers when there’s only air contact?
Respiratory epithelium
what type of epithelium Lines chambers when there’s air and food contact?
stratified squamous
what type of epithelium Lines chambers when there’s gas exchange?
thin squamous
URT: Respiratory epithelium
Pseudostratified, ciliated, columnar epithelium (with goblet cells)
URT: Function -> structure
Clean the incoming air
what do goblet cells of URT do?
secrete mucous
– Traps material
what do Ciliated cells of URT do?
Patterned movement -> current of mucus towards the pharynx
– swallowed and hydrolysed (digested) by stomach acid.
is there less mucous and more cilia or more mucous and less cilia in URT?
Lots of mucous less cilia
on a cold day what causes nose dribbles / runny nose?
cilia in your nose ‘cool down’ and stop ‘beating’
what does cigarette smoke do?
paralyses cilia,
increased particles -> increased mucous ->
accumulates ->
cough
URT epithelium
what does the nose consist of?
– Vestibule (just above/inside the nostrils), is lined with skin that contains sebaceous and sweat glands, and hair follicles (= protection)
– The hairs (vibrissae) filter coarse particles (dust, lint, pollen, ash etc.) from the inhaled air
whats the vestibule?
just above/inside the nostrils,
is lined with skin that contains sebaceous and sweat glands, and hair follicles (for protection)
whats vibrissae?
hairs that filter coarse particles (dust, lint, pollen, ash etc.) from the inhaled air
URT epithelium
what does the nasal cavity consist of?
– Olfactory mucosa
– Patch at the roof of the nasal cavity and contains smell (olfactory) receptors
URT Nose
what makes up the nose?
Bridge of nose
- 2 nasal bones
Nasal cartilages
flexible, patent
nostrils
- exteranl nares (anterior nares)
nose cartilages
– patent/ unobstructed airway
– soft/flexible
URT: Nasal cavity
what makes up the nasal cavity?
• Lateral walls - three projections – superior, middle and inferior conchae (turbinates) – stuck in mucous – cilia - moved to oropharynx – assists to clean the incoming air
what do the superior, middle and inferior conchae (turbinates) of the nasal cavity do?
curved structures on lateral wall
create turbulence, heavier particles fall to the epithelial surface
URT: Bones of nasal complex
• Nasal cavity • midline nasal septum anterior - hyaline cartilage posterior - bone • Roof • Floor • conchae - on lateral walls
what are the facial and cranial bones?
Frontal Nasal Palatine Maxilla Vomer Sphenoid Ethmoid
what is a sinus?
cavity within a bone – normally air filled)
what paranasal sinuses surround the nose?
frontal, sphenoid, ethmoid and
maxillary sinuses
URT: Paranasal Sinuses drain into the
pharynx
whats are the Paranasal Sinuses functions?
– lighten skull
– Increase area of RS epithelium (mucosa)
– clean, warm and moisten air
– sound resonance
blocked sinuses
Infected mucus can block the drainage
Lamina Propria
Epithelium lies on a layer of connective tissue
- Plexus of thin walled veins
what does the URT: lamina propria Plexus of thin walled veins do?
Help to warm the incoming air (act as a radiator).
what happens to the Plexus of thin walled veins if air temp drops?
vascular plexus dilates (a
greater volume of warm blood),
greater heat transfer.
where do nose bleeds originate from?
damage to these lamina propria plexus thin-walled
veins
what are the 3 pharynx of URT?
Nasopharynx
Oropharynx
Laryngopharynx
Nasopharynx
Choanae -> tip of soft palate
Auditory tube opening
Air only – RS epithelium
Oropharynx
Soft palate -> hyoid bone
Air and food
Stratified squamous
Laryngopharynx
Hyoid bone -> opening of larynx
Air and food
Stratified squamous
Lower RT: Larynx
where is larynx located?
Anterior/inferior to esophagus
Lower RT: Larynx
what is it made of?
Plates of cartilage – protects and maintains open airway
Lower RT: Larynx
what does it do?
Air only passage
– Surrounds, protects glottis (voicebox) – produces sound
– Swallowing, food has the ‘right of way’, no breathing
what happens when larynx close?
epiglottis pushed over to cover airway entry
draw larynx structure
ant view
epiglottis Hyoid bone thyroid laryngeal prominence cricoid cartilage rings trachea
draw larynx structure
sag view
thyroid Vestibular fold Vocal fold (vocal chord) cricoid arytenoid synovial joint -muscles to move vocal chords
draw larynx structure
post view
epiglottis
thyroid
arytenoid complex
cricoid
URT: Larynx – sound production
Membranes and ligaments lined with mucous membrane
arytenoid complex - Group of paired cartilages – arytenoid largest
Rima glottidis
Vocal fold
Vestibular fold
What type of epithelium lines most of the upper respiratory tract?
pseudostratified, ciliated, columnar epithelium containing goblet cells
What is the main function of pseudostratified, ciliated, columnar epithelium containing goblet cells epithelium?
to warm, humidify (moisten) and clean inhaled air
What is the main function of the epiglottis?
to protect the airway
Which of the following structures is NOT lined with pseudostratified columnar epithelium? A. frontal sinus B. nasopharynx C. trachea D. oropharynx E. superior conchae
D. oropharynx
What feature of the mucous membrane is very important in warming the incoming air?
the thin walled veins form an extensive plexus in the lamina propria and they dilate in the cold so there is more warm blood to warm incoming air
