what is the alveolar epithelium?
walls of the alveoli
where is the site of gas exchange?
at the capillaries between the alveoli
the opening of the trachea is called the
glottis
how many lobes does the right and left lung have respectivly
right has 3 and left has 2
why does the left lung have only 2 lobes?
because it has the cardiac notch to create more space for the heart
the conducting zone is a site for anatomical dead space. what is in the conducting zone from start to finish?
trachea - primary bronchi - secondary lobar bronchi - tertiary segmental bronchi - and terminal bronchioles
in the respiratory zone, the walls are thin enought for what to occur?
gas exchange
what structures are present in the respiratory zone from start to finish?
respiratory bronchioles, alveolar ducts , alveolar sacs, and alveoli
restrictive diseases primary effect what part of the lungs?
the respiratory zone/ alveoli
obstructive diseases thypically effect which part of the lungs?
the upper airways/ conducting zone
the interpleural space contains _____ and has what type of pressure?
contains pleural fluid and has negative pressure at around -4 cm H2O at rest
what are the regional differences in intrapleural pressure?
the pressure is more negative at the lungs apex and less negative at the lungs base
because of the pressure gradient, after a normal exhalation (FRC), why does fresh air mostly flow to the lungs bases?
because the pressure is more negative in the apices the alveoli located there are already fully expanded meaning no more air can flow in. in the bases the alveoli are not expanded so fresh air will mostly flow into the alveoli in the bases
after a forced exhalation, fresh air will primarily go to the apex alveoli, why is this?
because the residual volume is primarily in the bases and the alveoli there traps the gas. the alveoli in the apex is not full of trapped air so they are the first to receive fresh air.
what is the lung hilum aka the lung root?
this is the entry and exit point for bronchi, pulmonary arteries and veins, lymphatics, and nerves
where do lung tissue and bronchi receive their blood supply from?
the bronchial arteries which branches from the aorta
where does the deoxygenated blood from the bronchial circulation drain?
into the left atrium
what is the physiological consequence of the deoxygenated blood from the bronchial circulation being dumped into the left atrium?
deoxygenated blood mixes with oxygenated blood and dilutes the blood dropping the arterial PO2 by 2 or 3 mmHg
what are the boundaries of the thoracic cavity in the posterior, anterior, and lateral planes?
- thoracic vertebrae
- sternum (ends at xiphoid process)
- ribs and cotal cartilage
respectivly
what does it mean when you look at a lung CT/Xray and see a mostly black lung, Ground glass opacity, or condensation shadows?
- lung is filled with air
- alveoli is partially filled
- alveoli is filled with fluid
what respiratory muscles are used for expiration?
- internal intercostals and abdominal muscles
which muscle was considered an accessory muscle in breathing but is now considered a primary muscle?
scalenes, because they are active in every breath
what are the muscles of inspiration?
- sternocleidomastoid
- scalenes
- external intercostals
- interchondral part of internal intercostals
- diaphragm
which muscles are responsible in elevating the ribs?
the scalenes and intercostal muscles and diaphragm
