anatomy and histology of the respiratory tract Flashcards
conchae
warms and humidifies air
boney structure covered in mucosal membrane
large wet and warm surface area
larynx
structures enclosed by the thyroid cartilage
epiglottis
passive cartilaginous structure
held open by ligament, closed by fluid/food during swallowing
epiglottis duding swallowing
closed - so food doesn’t go into the airway
food goes around the sides
trachea
16 C shaped rings
C shape closed by smooth muscle (trachialis muscle)
allows room for oesophageal expansion (needed when swallowing food)
where does the trachea bifurcate
at the T4/T5 segment
how many C shaped rings
16
the lung generally
in the thoracic cavity on either side of the mediastinum, each surrounded by the plural cavity
lined by visceral pluera
suspended in the thoracic cavity
attached to the mediastinum via pulmonary root and ligament
lung is attached to the mediastinum via the
pulmonary root and ligament
lung is lined with
visceral pleura
lung is suspended in the
thoracic cavity
morphology of the lung
conical shape
rounded apex
broader base
3 surfaces of the lung
diaphragmatic surface
costal
mediastinal
the carina
where the trachea bifurcates into the bronchi
last area that has a cough reflex
cough reflex controlled through
vagus nerve
which bronchi is bigger
right
morphology differences in the bronchi
right is steeper and shorter
left lung
2 lobes
cardiac notch
lingula - occurs because of the cardiac notch
right lung
3 lobes
not always - often the horizontal fissure is incomplete or not present
pulmonary ligament
feature of the pulmonary root
a type of pulmonary mesentery
pulmonary root
feature surrounding the hilum
where the primary blood vessels and nerves and bronchi are going into the hilum
bronchi, bronchial arteries and pulmonary arteries
travel together
enter hilum superiorly
bronchial vessels
usually from ventral half of the aorta
supply connective tissue of lung as far as respiratory bronchioles
right lung drains to
azygous system
left lung drains to
hemiazygous system
impressions
subclavian vien/artery make an impression in the top anterior surface of the right lung
brachiocephalic vein and left subclavian artery make an impression on the top anterior of the left lung
rib impressions
ascending and descending component of the aorta make an impression on the left lung
azygous impression on the right lung
oesophagus and trachea make an impression
azygous impression found on which lung
right lung
bronchiopulmonary segments
functional units of a lung
the tertiary bronchus and the arterial branch supplying it
includes surrounding CT and bound with independent septa
how many bronchopulmonary segments in the right lung
10
how many bronchopulmonary segments In the left lung
9-10 due to the heart taking up some space
which lobes have more segments
the lower lobes because they have more surface area to hold them
lymphatics of the lung
distributed with blood vessels
output flow direction - collect from along the bronchus
feed into pulmonary nodes around bronchi
hilar nodes
found in the hilum of the lung
appear dark due to collected carbon from air
easier to see than pulmonary nodes
lung innervation
general visceral afferents - touch and stretch, noxious stimuli in airways
noxious stimuli
chemical irritants, ischaemia, excessive stretch
parasympathetic lung innervation
vagal branches
effect - bronchoconstriction and vasodilation
secretomotor to mucosal tissues
sympathetic lung innervation
T1-5 sympathetic ganglia
do vasoconstriction
(bronchodilatioon controlled via endocrine activity not nervous)
parasympathetic and sympathetic travel as components of
pulmonary plexuses
bronchodilation is controlled by
endocrine activity
pain in the lung
referred visceral pain
pain fibres travel with the sympathetics except for the trachea
referred through T1-T5 ganglia
can get referred pain through he shoulder but more commonly though the chest as a dull referred pain
trachea pain fibres travel with
transmitting pain fibres along the vagal branches instead
not felt in the lungs
pleural innervation
pleura take their innervation from the same sources as the tissue they are connected to
visceral pleura innervation
ANS and pain is the same as the lungs
sensation fibres only detect stretch
parietal innervation
takes innervation from the body wall
no parasympathetic fibres suppling the somatopleure doesn’t have parasympathetic innervation in the body wall
pressure, pain and temp travel with intercostal segmented nerves - able to identify pain specifically to an intercostal segment location
local somatic pain
parietal pleural pain
local somatic pain
felt to the specific ness of an intercostal segment
is there parasympathetic innervation in the body wall
no
pain in the diaphragmatic surface and mediastinal surface
referred pain to C3,4,5 through he phrenic nerves
conductive tube
conduct air
respiratory tube
gas exchange
order of the respiratory tree
primary bronchi secondary bronchi tertiary bronchi bronchioles terminal bronchioles respiratory bronchioles alveolar ducts alveolar sacs
functional unit of the respiratory tree
acinus
respiratory bronchiole onwards
terminal bronchiole
no more branches coming off
respiratory bronchiole
gas exchange starts due to some alveolus
alveolar ducts
have alveoli along them
at the terminal end - alveolar sac
lined by outpoucning alveoli
alveolar sac
a bunch of alveoli
as you descent the respiratory tree
less cartilage
more branches
more gas exchange
trachea and bronchi
conductive tubes
- respiratory epithelium
respiratory epithelium
psuedostratified columnar with goblet cells inbetween and cilia on top
not a gas exchange epithelium
cilia raft
mucus is excreted by goblet cells
psuedostratified columnar cells secretes serous fluid which sits within the cilia
mucus sits on the raft and gets shifted
goblet cells secrete
mucus
psuedostratified columnar cells secrete
serous fluid which sits between the cilia
component at the posterior edge of the trachea
trachialis smooth muscle
found in the muscular external of the trachea - replaces the cartilage
alveolar ducts terminate at
alveolar sacs
type 1 pneumocytes
squamous, large surface area for gas exchange
cover 95% of alveolar surface
fused basement membrane - blood-air barrier
type 2 pneumocyte
mare cuboidal in shape
makes up 5% of alveolar lining
synthesis and secretion of surfactant - reduces alveolarr fluid accumulation
alveolar macrophages
dust cells
patrol alveoli
- easily observed once they have ingested something
primary bronchi differences
primary bronchi - directly off the trachea
divde to form the secondary bronchi
divide again to form the tertiary bronchi
lobar bronchi
secondary bronchi
segmental bronchi
tertiary bronchi
supply a bronchial segment
