lecture 14 - overview & upper respiratory tract Flashcards
What is the function of the respiratory system?
Conduct warm, clean, moist air into close proximity with blood of the circulatory system for gas exchange. Also facilitates olfaction (smell) and produces sound
What are the 3 key functions of the respiratory system?
Gas exchange with circulatory system, producing sound, facilitating olfaction
What are the 3 key parts of the respiratory system?
Upper respiratory tract, Lower respiratory tract, Thorax
What are the key components of the thorax?
Thoracic cavity, joints, bones, respiratory muscles
What are the 2 key zones of the respiratory system?
Conducting and respiratory zones
What are the 2 key cavities of the Respiratory system?
Nasal and oral cavities
What is the entire respiratory tract lined with?
Epithelium called mucosa
What is the basic structure of the epithelium/mucosa that lines the respiratory tract?
Epithelium is attached via a basement membrane to the lamina propria
What are the 4 key types of epithelium found in different parts of the respiratory tract?
Respiratory epithelium, stratified squamous epithelium, simple squamous epithelium, olfactory mucosa
What type of epithelium is found in the majority of the conducting region of the respiratory tract ?
Respiratory epithelium
What type of epithelium is found in places where food (and air) travel?
Stratified squamous
What type of epithelium is found at the site of gas exchange in the respiratory tract?
Simple squamous
What type of epithelium is found at sites of olfaction?
Olfactory mucosa
What is the the histological structure of respiratory mucosa?
Epithelia, basement membrane, lamina propria (containing glands), Submucosa (containing glands)
What is the type of epithelium making up the respiratory epithelium?
Pseudo-stratified ciliated columnar epithelium (with goblet cells)
What is the meaning of pseudostratified?
A layer of cells that appears to be stratified - have several layers, but is actually just a single layer of (usually) columnar cells
What regions is respiratory epithelium found?
Nasal cavity, part of pharynx, larynx, trachea, bronchi
What cells in the respiratory epithelium make mucus?
Goblet cells
What is the function of mucus in the respiratory system?
Sticky substance that traps debris and moistens air
What is the structure and function of cilia on the respiratory epithelium?
hairlike organelles that beat back and forth to move mucus towards the pharynx where it can be swallowed and digested.
What are the 3 key components of the upper respiratory tract?
Nose & nasal cavity, paranasal sinus, pharynx
What is the common name for the pharynx?
Throat
What are the 3 parts of the pharynx?
nasopharynx, oropharynx, laryngopharynx
What is the function of the nose in terms of respiration?
It’s the primary passageway for air entering the respiratory system
What is the bridge of the nose made up of?
2 nasal bones
What is the end of the external nose made up of?
Cartilage
What is the structure and function of the cartilage of the nose?
Soft flexible cartilage that maintains a patent/unobstructed airway
What is the medical name for the nostrils?
External nares
What are the external nares?
The nostrils
What is found immediately inside the nostrils/external nares?
Vestibule, lined with skin
What is the structure of the vestibule of the nose?
Lined with skin and contains sebaceous glands, sweat glands, hair follicles (vibrissae)
What is the name for the hairs found in the vestibule of the nose?
Vibrissae
What is the function of vibrissae?
They filter air
What is the structure of the nasal septum?
Made up of cartilage anteriorly and bone posteriorly
What bones form the roof of the nasal cavity?
Ethmoid and sphenoid bones
What is the floor of the nasal cavity formed by?
The hard and soft palates
What are the relative positions of the hard and soft palates?
Hard anterior, soft posterior
Where are conchae found?
On the lateral walls of the nasal cavity
How many conchae are there?
3
What are the names of the 3 conchae?
Superior, middle and inferior
What is the alternative name for conchae?
Turbinates
What covers the surface of the conchae?
Respiratory epithelium
What is the function of the conchae?
Swirl inspired air so that foreign particles stick to the mucosa, and increase time for warming and humidifying of air and olfactory detection
What is nasal epithelium made up of?
Mostly of respiratory epithelium, but also contains a specialised area of olfactory epithelium
Where are the olfactory receptors found?
The roof of the nasal cavity, in olfactory epithelium
What feature of the nasal mucosa helps to warm incoming air?
Vascular plexus of blood vessels that sits close to surface
What happens to the vascular plexus of the nasal cavity when air temperature drops?
Plexus dilates for greater heat transfer
What is a paranasal sinus?
Cavities in the bones surrounding the nasal cavity
What bones are the paranasal sinuses found within (4)?
Frontal, sphenoid, ethmoid and maxillary bones
What are the paranasal sinuses lined with?
Respiratory mucosa
Where do the paranasal sinuses drain?
Into the pharynx
What are the functions of the paranasal sinuses (3)?
Lighten skull, increase surface area to clean, warm and moisten air, sound resonance
What is the cause of blocked sinuses?
Infected mucus blocks paranasal sinus drainage
What is the overall structure of the pharynx?
Muscular funnel shaped tube shared by the respiratory and digestive system
What passes through the nasopharynx?
Air only
What lines the nasopharynx?
Respiratory mucosa
Where is the nasopharynx located?
Posterior to the nasal cavity, anterior to the oro- and laryngo- pharynxes
Where does the nasopharynx extend?
From posterior nares to the soft palate
What structures block the nasopharynx during swallowing to prevent food entering the nasal cavity?
The soft palate and uvula
Where do the auditory tubes drain to?
The nasopharynx
Where do the auditory tubes drain from?
The middle ear
What part of the pharynx are the pharyngeal tonsils found?
Posterior wall of the nasopharynx
What passes through the oropharynx?
Air and food
What is the oropharynx lined with?
Stratified squamous epithelium
What is the fucntion of the stratified squamous epithelium of the oropharynx?
Protects against abrasion, e.g. from food
Where is the oropharynx located?
Posterior to the oral cavity and inferior to the nasopharynx, superior to the laryngopharynx
What are the boundaries of the oropharynx?
From the palate to the hyoid bone
What tonsils are found in the oropharynx?
The palatine and lingual tonsils
What part of the pharynx are the palatine and lingual tonsils found in?
The oropharynx
What passes through the laryngopharynx?
Air and food
What is the laryngopharynx lined with?
Stratified squamous epithelium
What are the boundaries of the laryngopharynx?
From the hyoid bone superiorly to the opening of the larynx/beginning of oesophagus inferiorly, where the respiratory and digestive tracts diverge
