Lecture 14: The Upper Respiratory Tract Flashcards
What is the role of the respiratory system?
Conducts warm, clean, moist air into close proximity with blood of the circulatory system for gas exchange
What is the respiratory system?
Connected organs/structures that perform functions
To be effective what does the respiratory system need?
3
- A surface for gas exchange
- A path for air to flow to reach the gas exchange surface in optimal condition
- Ability to draw breath in and out
What is needed as a part of an efficient gas exchange surface?
Blood and air to be close, but not in contact
What are 2 additional function of the respiratory system?
- Produce sound
- Olfaction
What does URT stand for?
Upper respiratory tract
What does LRT stand for?
Lower respiratory tract
What are the main components of the respiratory system?
5
- URT
- LRT
- Thoracic cavity
- Joints
- Respiratory muscles
What is a function of the Nasal cavity?
Olfaction
What is a function of the Oral cavity
Passage for air and food
Where does the Conducting region stem?
The nose to bronchioles
What is a function of the conducting region?
Ensure air is warm, clean and moist
What is a function of the Respiratory region?
Sites of gas exchange
What is included in the Respiratory region?
Alveoli
What are most body organs lined with?
A mucosa
What is mucosa composed of?
Epithelia attached via a basement membrane to the lamina propia
What is the lamina propia?
Connective tissue, which may contain glands
What is usually below the mucosa?
Submucosal layer
What may be contained in the submucosal layer depending on the region?
Glands
What is the respiratory tract lined with?
Mucosa
What happens to the epithelium along the respiratory tract?
It changes to reflect function
What is most of the conducting region lined with?
Respiratory epithelium
What is the area where air and food travel lined with?
Stratified squamous epithelium
What is the site of gas exchange lined with?
Simple squamous epithelium
What is Olfaction lined with?
Olfactory mucosa
What is the description of respiratory epithelium?
Pseudostratified ciliated columnar epithelium (with goblet cells)
What do Goblet cells produce?
Mucus
What does mucus do?
Traps debris, moistens air
What do ciliated cells do?
Produce patterned movement that pushes mucus towards the pharynx
What can happen to mucus in the respiratory tract?
Swallowed and digested by stomach acid
What are the components of the URT?
3
- Nose & Nasal cavity
- Paranasal sinuses
- Pharynx
What are the components of the Pharynx?
3
- Nasopharynx
- Oropharynx
- Laryngopharynx
What is the function of the URT?
Conducting passage, that prepares air for the respiratory membrane making it warm, clean and moist
What are paranasal sinuses?
Resonating chambers for speech
What is olfaction made of?
Sensory receptors for smell
What is the primary passageway for air?
The nose
What is the bridge of the nose made of?
2 nasal bones (nasal septum)
What are the physical features of the nose cartilages?
2
- Soft
- Flexible
What is the function of cartilages in the nose?
Maintain patent/unobstructed airways
What is contained within the nostrils of the nose?
External/anterior nares
What is the nose?
A vestibule lined with skin
What are accessory features found within the nose?
2
- Sebaceous/sweat glands
- Hair follicles
What filters inhaled air in the nose?
Vibrissae (hairs of the nose)
Where is the nasal septum?
In the midline of the nasal complex
What is the anterior and posterior of the nasal complex made of?
(2)
- Anterior is cartilage
- Posterior is bone
What do the internal/posterior nares open into?
The nasal pharynx
What is the roof of the nasal cavity formed by?
Ethmoid and Sphenoid bones
What is the floor of the nasal cavity formed by?
Hard and soft palates
What are on the lateral walls of the the nasal complex?
Conchae
What are Conchae?
Projections from the nasal wall
What are the names of the 3 conchae?
- Superior
- Middle
- Inferior
What covers Conchae?
Respiratory epithelium
What is the function of Conchae?
Cause inspired air to swirl and cause particles to stick to the mucosa, allowing more time for warming/humidifying of air plus olfactory detection
What’s the Nasal cavity covered with?
Respiratory epithelium with an area of olfactory mucosa
What is contained within an area on the roof of the nasal cavity?
smell (olfactory) receptors
What does the epithelium sit on top of?
Lamina propia
What does the plexus of thin walled veins in the nasal mucosa do?
Helps warm incoming air (radiation)
What happens when cold air comes into the nasal mucosa?
The vascular plexus dilates meaning greater heat transfer
What are sinus’s?
Cavity’s within a bone
What does paranasal mean?
Surrounding the nose
Where are paranasal sinus found?
Within frontal, sphenoid, ethmoid and maxillary bones
What are paranasal sinuses lined with?
Respiratory mucosa
Where do the sinus drain?
Into the pharynx
What are functions of the Paranasal sinuses?
3
- Lighten skull
- Increase surface area to clean, warm, moisten air
- Sound resonance
What can infected mucus do to paranasal sinuses?
Block drainage leading to blocked sinus
What is the Pharynx?
A muscular funnel shaped tube shared by respiratory and digestive system
What is the pharynx commonly called?
The throat
What are the 3 regions of the Pharynx?
- Nasopharynx
- Oropharynx
- Laryngopharynx
What is the nasopharynx a passage for?
Air only
What lines the Nasopharynx?
Respiratory mucosa
Where is the Nasopharynx located?
From the posterior of the nasal cavity (posterior nares) to the soft palate
What blocks the nasopharynx during swallowing to prevent food entering the nasal cavity?
Soft palate and uvula
Where do auditory tubes drain from into the nasopharynx?
The middle ear
What is on the posterior walls of the Nasopharynx?
Pharyngeal tonsils
What is the Oropharynx a passage for?
Air and food
What lines the Oropharynx?
Stratified squamous epithelium to protect against abrasion
Where is the Oropharynx?
Soft palate to hyoid bone
What 2 tonsils are present in the oropharynx?
- Palatine
- Lingual
What is the Laryngopharynx a passage for?
Air and food
What is the Laryngopharynx lined with?
Stratified squamous epithelium
Where is the Laryngopharynx?
From the hyoid bone to opening of the larynx/beginning of the esophagus
What has right of way along the Laryngopharynx whilst swallowing?
Food