respiratory system Flashcards
what’s the function of the respiratory tract
gas exchange
sense of smell
phonation/speaking
why do we need the air to be humid
to keep the respiratory tracts moist so it can attract pathogens
why does the air need to be warm
gas exchange happens at optimal temp which is body temp
what is the frontal and sphenoid sinus
areas that hold mucus in skull
where are the turbinates located
in the nasal cavity
what are the 3 turbinates
inferior
middle
superior turbinatw
what is the structure and role of turbinates
mucus lined bony structures that
- increase surface area of nasal cavity
- makes air turbulent increasing its contact with the mucous (help add moisture to air and warm it up)
why is the nasal cavity highly vasulated
lots of blood vessels that run in opposite to air flow which allows heat exchange
what are the 3 pharynx
nasopharynx
oropharynx
laryngopharynx
what is the epiglottis
flap that goes over the larynx to close it
what 2 types of cartilage are found at the larynx (voice box)
thyroid
cricoid
what is the purpose of membranes between the tracheal caritlage
give them more flexibility
what do you call the point where the trachea bifurcates
carina
what feature of the trachea allows it to open and close
the trachealis (smooth muscle) tightens or relaxes
describe the structure of the trachea
- trachealis smooth muscle
- mucose (pseudostratified ciliate columnar epithelia)
- submucosa (contains connective tissue with sub mucous glands)
- c shaped cartilage (keep it open, gives more flexibility to open and close
- lumen
what is the use of cilia in trachea
waft and beat the mucous up to the throat so it can be swelled and stomach can kill the pathogens
why is there only sqamous cells towards the end of the trachea
thin for better gas exchange
how does smoking affect cilia
paralyses cilia so cant waft the mucous up, potentially harbouring pathogen causing infection
what cells produce the mucoius
goblet cells and glands
why do respiratory disease affect terminal bronchial more
because the c cartilage is terminated leaving only smooth muscle so they effect it as it is doesnt have the cartilage to keep it open
what type of epithelia is found in the trachea
psedostratified ciliated columnar
what type of epithelia is in the alveoli
simple squamous
describe how structures in the thoracic cavity change during ventilation
sternum and ribs move up and outwards
diaphragm contracts inferior
all to increase thoracic volume
what 2 [arts of the diaphragm are there
left and right hemi diaphragm
why does the right hemisphere diaphragm sit higher
because the liver sits underneath
what do all the muscle fibres on the semi diaphragms connect to
the central tendon
what happens when the diaphragm contracts
the muscle fibres on the diaphragm pull down on the central tendon to increase thoracic volume
what level does the inferior vena cave pass through the diaphragm
T8 (venacava has 8 letters)
what level does the oesophagus pass through the diaphragm
T10 (oespophagus has 10 letters)
what level does the descending aorta pass through the diaphragm
T12 (aortichiatus hole that aorta travels thru in diaphragm has 12 letters)
what is the prefix relating to the diaphragm
phrenic
what level is the phrenic nerve at
c3 c4 c5
(c3 c4 c5 keeps the diaphragm alive)
what 6 muscles are used in inspirations
Pectoralis major,
Pectoralis minor,
External intercostals,
Scalenes,
Serratus anterior,
Innermost intercostals
what 3 muscles are used in expiration
Internal intercostals,
Abdominal muscles,
Innermost intercostals
explain how the diaphragm moves to accommodate exhale and inhaling
inspiration = diaphragm contracts so pressure in thorax decreases, causing air to enter lungs down a pressure gradient
expiration = diaphragm relaxes so pressure in thorax increases, causing air to leave lungs down a pressure gradient
what is the pressure b/q layers of Plura compared to atmospheric pressure
lower (756 mmg vs 760mmg)
Roughly what age does our bronchial tree stop growing?
18
Which pneumocytes produce surfactant
type 2
Who is particularly vulnerable to not being able to produce surfactant?
pre mature babies
what does surfactant do
keeps alveoli to stay open by making sure they dont stick and clsoe
compared the SA of alveoli in adults to babies
kids = 2.8m2
adults = 75m2
what happens if the oesophagi-tracheal septum dont form in babies
fistula , abnormal connection between oseophagus and trachea
needs surgical repair
how many bronchopulmonary segments are there on the left vs the right
left = 10-8
right = 10
(as left lung is smaller)
what is bronchopulmonary segment
smallst functional unit of lung
(each bronchopulmonary segment has its own pulmonary supply)
each segment has a septum running between them
what provides lung muscle with oxygen
bronchial artery, vein and nerve
why is the right bronchial more prone to choking
right bronchial is wider, shorter and at a more vertical angle
how many lobes are in right and left lugn
right = 3
left = 2
what are the fissures called in each lung
left = 1 oblique fissure
right = horizonta (separates UL AND ML) l and oblique (separates LL AND ML) fissure
why is it hard to see disease in apex
because it runs 3 cms above apex
at what landmark in the lungs do structures to enter and exit lungs to supply blood
hilum
what is the function of the pulmonary ligament
stabilises the lung
free moving in pleural cavity but ligament holds the hilum in place to stop it twisting and ripping the pleura
