lecture 15 Flashcards
what are the components of the lower respiratory tract
Larynx, trachea, Bronchi, Bronchioles Alveoli
functions of the LRT
- Conducts air to/from the site of gas exchange
- Completes cleaning, warming and humidifying
of air - Provides a barrier between the air and blood, and a large surface area for gas exchange
where do we find the larynx and whats its boundaries
Anterior to esophagus
From the hyoid bone to the trachea.
the larynx is a passage for air only how do we get around this
Cartilages protect and maintain an open airway (patent)
* Epiglottis closes over the airway when swallowing
what cartilages do we find around the larynx
Thyroid cartilage, Cricoid cartilage, eppiglottis
whats laryngeal prominence and where do we find it
The middle of the thyroid cartilage is the Laryngeal prominence. This cartilage for men grows thicker and more pointed in puberty giving the adams apple to teenage boys.
where do we find cricoid cartilage
Cricoid cartilage is a solid ring around the whole tube and its just above the trachea.
where do we find the eppiglottis and whats it do
On top of the trachea is the eppiglottis, the epiglottis functions to protect the glottis. Epiglottis is made of cartilage, when swallowing this closes to seal the trachea so no food gets into the airway.
whats the glottis colloquially
the voice box
what are the vocal folds and vestibular folds attached to
cartilages
vocal folds, location, function,
they are lower in the glottis than the vestibular folds, This is the “true vocal cord” as air passing pass these cause vibrations which is sound waves. These are the normal vocal cord as these are the ones used for normal phonation.
what does testosterone do to the vocal folds
Testosterone affects cartilage and muscle, resulting in longer, thicker folds = deeper voice
describe vestibular fold location and function
’False’ vocal cords, Superior to vocal folds, Prevent foreign object entry to glottis
Can produce very deep sounds
location and function of the trachea
Anterior to esophagus, Between the larynx and primary bronchi.
maintain patent airway, clean warm and humidify
structure of the trachea
It can achieve this by a band of smooth muscle called the trachealis. This trachealis connects the two ends of the c-shaped cartilage rings. This band has mainly elastin fibres in lamina propria and submucosa. also has respiratory epithelium lining
what causes coughing and why we do it
Coughing is another mechanism of removing debris from the respiratiory tract. As it coughs out all debris that were on the mucosal layers.
the trachealis muscles contract to produce coughing
how many lobes in each lung and why
3 lobes in the right, 2 in the left because of the heart position
whats the hilum
the point in the lungs where the bronchi and blood vessels enter the lungs
whats the path of the bronchial tree
trachea, primary bronchi, secondary lobar bronchi, tertiary segmental bronchi, bronchioles and terminal bronchioles
describe epithelium and structure of the primary bronchi
it has respiratory epithelium and complete Cartilage and smooth muscle rings complete
describe the epithelium and structure of the secondary and tertiary bronchi
the cartilage rings becomes cartilage plates the respiratory epithelium starts to decrease in height and goblet number starts to reduce
whats the make up of the respiratory zone of the lungs
Pulmonary lobules made of many alveoli (air sacs) arranged like bunches of grapes, surrounded by dense capillary network
whats the epithelium of the alveoli
Alveolar walls very thin: simple squamous epithelium on a thin basement membrane
what are the two types of cells in the alveoli
type 1 and type 2 pneumocytes
describe the type one pneumocyte
Type I squamous
* Forms the respiratory membrane/blood-air barrier with capillary wall and shared basement membrane
describe the type 2 pneumocyte
Type II cuboidal
* Scattered amongst Type I
* Secrete surfactant, a complex lipoprotein (phospholipid) that reduces the surface tension of the alveolar fluid
what makes the respiratory membrane
the alveolar cell layer of type one pneumocytes covered in surfactant, a fused basement membrane then the capillary endothelium
