The Respiratory System Flashcards
Give general overview of respiratory system (3)
right lung bigger than left
nose filters through 4 stages
alveolar epithelium cover surface area of 100m^2 & contains over 700 million individual alveoli
How are lungs kept partially inflated?
by rigidity of the chest wall, which resists the tendency of lungs to collapse
what happens to the pressure of the lung because of the rigidity of the chest wall
causes a slight sub atmospheric pressure between outer surface of the lung and the inner wall of the thorax
why does fluid cover the pleural membranes (lung surfaces)?
allows movement of the lungs within the thoracic cavity
why is mouth breathing bad?
the air bypasses the 4 stages and therefore causes sores throats, illnesses, infections
what are the major functions of the respiratory system? (4)
air conditioning
regulating the pH of blood
olfaction
phonation
what cell type do serous membranes have?
simple squamous epithelium
what does the mesothelium cover?
closed body cavities
what is serous tissue also called?
mesothelium
what type of cancer can occur in the mesothelium?
mesothelioma- cancer from xposure to asbestos
what is the tissue surrounding the lung called?
parietal or visceral pleura
which cavities does the mucosa cover? (4)
gastrointestinal
respiratory
urinary bladder
uterus
what are the respiratory zones? (4)
respiratory bronchioles
alveolar ducts
alveolar sacs
alveoli
what are the conducting zones? (8)
nose
nasal cavity
pharynx
larynx
trachea
bronchi
bronchioles
terminal bronchioles
what is the function of the respiratory zones?
conduction- they deliver inspired air into the gas exchanging zones
what does the nasal cavity provide? (2)
a large SA for warming and moisturizing inspired air
trapping inhaled particulate matter
describe the architecture of the nose
nasal cavities are paired chambers separated by bony and cartilaginous septum
name the 3 regions the chambers are divided into
vestibule
respiratory region
olfactory region
what kind of glands does the nasal and sinus submucosa contain? (2)
mucous
serous
what is the vestibule of the nasal cavity?
forms a part of the external nose and communicates with external environment
what is the vestibule lined with?
non-keratonised stratified squamous epithelium
what does the vestibule contain?
vibrissae (stiff hairs)
what type of cell do stratified squamous epithelium transition to away from the vestibule?
pseudo-stratified epithelium with occasional mucous goblet cells
what is meant by pseudo stratified columnar epithelium?
they are tall, singular layers of cells on a basal layer and the nuclei are positioned in a way that is similar to stratified epithelium
what do you expect to see when looking at respiratory epithelium?
a stacking of nuclei as the cells are mostly 2 layers of cells stacked on top of each other
what is the function of a stratified epithelium?
protective
what are the 5 cell types you would see in the respiratory epithelium?
ciliated epithelial cells
goblet cells
brush cells
kulchitsky cells
basal cells
what are conchae?
shelf like bony projections which cause folds in the nose
what is the role of the conchae? (3)
divide nasal cavity into separate air chambers
increase the SA and cause turbulence in air flow
increases the efficiency with which the inspired air is warmed & filtered
where is the olfactory mucosa located?
roof of nasal cavity
what type of epithelium does the olfactory mucosa have?
pseudostratified columnar epithelium
what gives mucosa its yellowish-brown colour?
lipofuscin in the supporting cells
what is the role of supporting cells in the olfactory mucosa?
provide mechanical and metabolic support to olfactory receptor cells
also synthesise and secrete odorant bidning proteins
what is teh Bowman’s gland?
a short duct which penetrates the olfactory epithelium
what is the function of the Bowmen’s gland?
produces a secretion which can act as a solvent in which odorous substances dissolve
what is lipofuscin stained with?
long ZN staining method
what is the long ZN staining useful for?
diagnosing degenerative neuro metabolic disorders
explain the olfactory vesicle
a cell which has long, thin cilia rising from the olfactory vesicle and extend to the surface of the epithelium. the cilia detect odor molecules. the basal end of the cell has an un-myelinated axon. collections of these axons are grouped together that pass through a thin plate of the ethnoid bone - looks like a colander with spaghetti through the holes
where do these axons end up?
enter the olfactory bulb of the brain
what are the two main causes of inflamation of the nose?
Rhinitis; such as hey fever and common cold
nasal polyps
what is the pharynx?
passageway for air and food
what does the pharynx connect?
connects the nasal and oral cavities to larynx and oesophagus
what is the pharynx divided into? (3)
nasopharynx
oropharynx
laryngopharynx
what is MALT?
mucosa associated lymphoid tissue
what is the function of MALT?
samples inhaled antigenic material and prepares defense mechanisms against it
what does the laryngeal region compromise of? (3)
epiglottis
true vocal cords
false vocal cords
what is the function of the larynx/laryngeal region? (3)
prevents inspired air entering the oesophagus
prevents ingested food and fluid entering trachea
permits the production of complex sounds
describe the epiglottis
consists of a sheet of elastic cartilage covered by mucosa on both sides
how does the epiglottis prevent food/liquids passing into the trachea?
closes the tracheal opening when swallowing
what type of cell covers interior surface of the epiglottis?
non-keratinised stratified squamous epithelium
what type of cell covers the posterior surface?
two types of cells; upper half is stratified squamous epithelium, lower half is covered ciliated in pseudo stratified columnar epithelia
what allows for the lubrication of the oesophagus?
serous mucus glands in the lower half of the epiglottis secrete substance
what is the function of stratified squamous epithelium?
provide protection to underlying tissue
why does the epiglottis need protection?
abrasions from movement and food
what are vocal cords?
the laryngeal mucosa is pushed out into the laryngeal lumen to form two pairs of folds
what is the function of the true vocal cords?
responsible for the production of sound by vibrating in a stream of forcibly expressed air
what is the function of the false vocal cords?
they modify the sound produced by the vibrating true cords
how else is sound modified?
by the vibration around the nasal and oral cavities and the control imposed on the sound emitted by movements of the tongue and lips
what type of cells are the true vocal cords covered in?
non-keratinised stratified squamous epithelium
why are the true vocal cords covered in stratified squamous epithelium?
because they are subject to mechanical stress
what is the most frequent malignant tumour of the larynx?
squamous cell carcinoma, affects males> 40yrs who smoke
what is under the larynx?
trachea
how many layers does the trachea have?
4 and lined with respiratory mucosa
describe the shape of the trachea
has 15-20 C- shaped hyaline cartilage rings and bifurcates into 2 main bronchi
what is the pericardium?
the pericardium is a dense connective tissue surrounding the C-shaped cartilage
explain cystic fibrosis (4)
inherited metabolic disease
mutation in the CFTR protein
cells unable to move chloride, sodium ions, and water effectively
susceptible to lung infections, pseudomonas aeruginosa & aspergillus, staph aureus
explain cystic fibrosis (4)
inherited metabolic disease
mutation in the CFTR protein
cells unable to move chloride, sodium ions, and water effectively
susceptible to lung infections, pseudomonas aeruginosa & aspergillus, staph aureus
where do the main bronchus enter in the lungs
the hilum with pulmonary arteries
where does the conducting zone of the respiratory tract stop?
the terminal bronchiole
describe the alveoli (2)
terminal air spaces
sites of gas exchange
describe type 1 pneumocytes (4)
thin simple squamous cells
not capable of cell division
compromise of 40% of alveolar lining cells
lining 95% of the surface of alveoli
describe type 2 pneumocytes (7)
secretory cells
stem cells for Type 1
60% of alveolar lining cells
only cover 5% of alveolar air surface
cuboidal in shape
mixture of phospholipids, neutral lipids and proteins
have microvilli on surface
what is a closed method of biopsy?
performed through the skin or through the nasal cavity with an endoscope
what is an open method of biopsy?
operation under general anaesthesia
give examples of closed methods (4)
laryngoscopy
bronchoscopy
needle biopsy
thoracoscopic biopsy (VATS)
How is a laryngoscopy/broncoscopy conducted
thin, flexible fibre optic tube with a light and camera at the end is shoved through the nose
what is used to decalcify specimens? (5)
nitric acid
hydrochloric acid
formic acid
EDTA
trisodium citrate
what is true cut biopsy?
a biopsy needle called a Temno is used to collect a biopsy sample
explain a thoracoscopy biopsy (VATS)
3 incisions are made through chest wall into chest cavity
explain asbestosis (3)
long term inflammation and scarring of lungs from asbestos
causes shortness of breath, cough, wheezing, and chest pain
leads to lung cancer or pulmonary heart disease
