lecture 15 - lower respiratory tract Flashcards
what are the functions of the lower respiratory tract
- 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 for gas exchange
what passes through the larynx
passage for air only
where is the larynx located
anterior to the oesophagus
where does the larynx go to and from
from the hyoid bone to the trachea
what do cartilages in the larynx do
protect and maintain an open airway (patent)
what does the epiglottis do
closes over the airway when swallowing
what is the glottis
voice box
what are the two folds attached to the cartilages of the larynx
vocal folds and vestibular folds
what are the vocal cords also called
the ‘true’ vocal cords
what are the vestibular cords also called
the ‘false’ vocal cords
what causes sound waves in the vocal cords
the passing of air causes vibrations
what are the vocal cords used for
normal phonation
why do men have a deeper voice than women
testosterone affects the cartilage and muscle = resulting in longer, thicker folds - deeper voice
where are the vestibular folds located
superior to the vocal folds
what do vestibular folds prevent
foreign object entry to glottis
what can vestibular folds produce
very deep sounds
where is the trachea
anterior to the oesophagus
where does the trachea go to and from
the larynx and the primary bronchi
what is the function of the trachea
- maintain patent airway
- clean, warm and humidify air
what are the shapes of the cartilage rings in the trachea
c shaped
what are the trachealis
band of smooth muscle that connects the ends of cartilage rings
what is the function of the trachealis
contract for coughing
what is the muscularly escalators function
to remove debris to the pharynx to be swallowed and digested
what coats the surface of the muscularly escalator
mucus from goblet cells and mucus glands coat the surface
how many lobes does the right side of the lung have
3 lobes on the right
how many lobes does the left side of the lung have
2 lobes = to make room for the heart
what is the hilum
where bronchi and blood vessels enter
what is the apex of the lung
the superior region
what is the coastal surface of the lung
the lateral surface, against the ribs
what is the base of the lung
inferior, sits on the diaphragm
what is the epithelium of the primary bronchi
respiratory epithelium
what is the epithelium of the secondary and tertiary bronchi
respiratory epithelium starts to decrease in height, goblet cell numbers reduce
what is the epithelium of the bronchioles
cuboidal epithelium
what is the cartilage like in the secondary and tertiary bronchi
cartilage plates
what is the cartilage like in the bronchioles
no cartilage but thick sooth muscle for bronchoconstriction/dilation
what are the pulmonary lobules and what are they made of
made of many alveoli (air sacs) arranged like bunches of grapes
what are the alveolar walls like
alveolar walls are very thin : simple squamous epithelium on a thin basement membrane
what are the external surfaces alveoli covered in
a fine network of pulmonary capillaries
what are the structure of alveoli like
pocket like, open at one side
what are alveoli covered in
by a dense capillary network
what are lung epithelial cells called
pneumocytes
what are the type 1 pneumocytes
squamous epithelial cells
what are type 1 pneumocytes function
forms the respiratory membrane / blood-air barrier with capillary wall and shared basement membrane = gas exchange
what are the type 2 pneumocytes
cuboidal epithelial cells = scattered amongst type 1
what is the function of type 2 pneumocytes
secrete surfactant, a complex lioprotein that reduces the surface tension of the alveolar fluid
what do roaming macrophages do in the alveoli
removes any debris that makes it to the alveoli
