E-learning 3 respiratory system Flashcards
what can the respiratory system be divided into
upper respiratory tract and lower respiratory tract
what does upper respiratory tract include
the nasal cavity and paranasal sinuses
the pharynx
the larynx, above the level of the vocal folds
the purpose of the upper respiratory system is to condition inspired air before it reaches the lungs. before reaching the lungs air is…
warmed to body temperature
humidified
filtered for particulates
what does the lower respiratory tract include
the larynx below the level of the vocal folds
the trachea
the bronchi
the bronchioles
the lungs
what happens in the lower respiratory tract
gas exchange
what controls the rhythm of breathing
brainstem
where is the respiratory center located in the brain
medulla oblongata
when are the inspiratory neurons active and when are they inactive
active during inspiration
inactive during expiration
what neurons are active during expiration
expiratory neurons
this rhythm can be modified by the afferent information. where does the afferent information come from
chemoreceptors
the brain
receptors in the lungs
what is the function of the lungs
to oxygenate blood
why is the right lung large than the left
heart bulges more into the left
what are the lungs surrounded by
pleural cavities
pulmonary arteries delivery deoxygenated blood to the lungs from what chamber of the heart
right ventricle of the heart
oxygenated blood returns to the left atrium via which vessels
pulmonary veins
what is the apex of the lungs
the top of the lungs which extends superiorly into the root of the neck, above the first rib
what are the three surfaces of the lungs
costa
mediastinal
diaphragmatic
what is the costal surface
the front of the lungs, close to ribs and intercostal spaces
what is the mediastinal surface
the inside surface of the lungs, close to the mediastinum anteriorly and vertebral column posteriorly
what does the mediastinal surface contain
this surface contains the hilum of the lung
what is the diaphragmatic surface
base of the lungs, sits on the diaphragm
what are the three borders of the lungs
inferior border
anterior border
posterior border
what does the inferior border separate
the base from the costal surface
what does the anterior border separate
separates costal surface from mediastinal surface
what is the posterior border
separates costal surface from the mediastinal surface (this bored is smooth and rounded unlike the others)
the right lung has how many lobes
3
the left lung has how many lobes
2 lobes
what divides the lungs into lobes
the horizontal and oblique fissures
the right lung has what 3 lobes
superior, middle and inferior
the oblique fissure separates the…
inferior lobe from the superior and middle lobe
the horizontal fissure separates the…
superior lobe from the middle lobe
what 2 lobes does the left lung have
superior and inferior lobe
what fissure separates the inferior and superior lobes
oblique fissure
what is the name of the tongue like projection that extends over the anterior surface of the heart
lingula
the lungs attach to the hear and trachea by several structures that are collectively referred to as the roots of the lung, the areas at which these structures enter and leave the lung is knows as the
hilum of the lung
structures that makeup the root of the lung and enter/leave at the hilum include
a pulmonary artery
2 pulmonary veins
a main bronchus
bronchial vessels
nerves
lymphatics
which structure in the hilum has the thickest and strongest walls
bronchi
what structure has the second thickest walls
pulmonary arteries
which structure has the thinnest walls
pulmonary veins
superiorly to inferiorly, where do the structures enter the hilum
top:
pulmonary artery
bronchi
pulmonary veins
bottom:
at what level does the apex lie
level T1 (just above the first rib)
the most inferior part of the lungs lies at what level
T12 (in contact with the diaphragm)
where does the oblique fissure lie (posteriorly, laterally and anteriorly)
posteriorly - T4
laterally - crosses the 4th and 5th intercostal spaces to reach rib 6
anteriorly - follows rib 6 and its costal cartilage
where does the horizontal fissure lie
lies anteriorly following the contour of rib 4
the lungs are enclosed by a thin membrane known as the
pleura
the pleura associated with the lungs (inside layer) is known as the
visceral pleura
the pleura associated with the walls of the cavity (outside layer) is known as the
parietal pleura
the space between the two layers of pleura is a potential space known as the
pleural cavity
potential space is a cavity that does not normally exist in healthy people. it has the potential to become a space in illness or injury
the function of the pleura and serous fluid is to
allow smooth movement of the lungs as they expand and collapse throughout respiration
the fluid also provides surface tension that keeps the surface of the lung in contact with the thoracic wall
regions of the parietal pleura
costal pleura (covers the internal surfaces of the thoracic wall)
mediastinal pleura (covers the lateral aspects of the mediastinum)
diaphragmatic pleura (covers the superior aspect of the diaphragm on each side of the mediastinum)
cervical pleura (extends through the superior thoracic aperture forming domes pleura over the apex of the lung)
if a significant amount of air or fluid enters the pleural cavity what is broken? what does this cause?
the surface tension adhering the visceral and parietal pleura causing the lung to collapse
what is hydrothorax
accumulation of fluid in the pleural cavity
what is haemothorax
if blood enters the the pleural cavity as a result of injury
what do the bones of the thorax consist of
sternum
12 pairs of ribs and their costal cartilages
12 thoracic vertebra (T1-T12)
what do the bones of the thorax provide
attachment points for the muscles of respiration
they move to facilitate breathing
provide protection for the vulnerable organs within the thorax
the sternum its anteriorly, what does it consist of
manubrium (at the top)
sternal body (in the middle)
xiphoid process (at the bottom)
what are ribs 1-7
true ribs
true ribs articulate directly with the sternum via short costal cartilages
what are ribs 8 - 12
false ribs
false ribs articulate indirectly with the sternum via long shared costal cartilages
what are ribs 11 - 12
floating ribs
they do no articulate with the sternum anteriorly and are shorter and pointier than the other ribs
thoracic vertebra
the 12 thoracic vertebra make up the posterior element of the thoracic cage
they articulate with the ribs and with each other
what does the diaphragm separate
the thorax from the abdomen
whats the large flat bit of the diaphragm called
the central tendon
what is the diaphragm attached to
the lower ribs and vertebral column
what is the diaphragm innervated by
the left and right phrenic nerves
where are the origins of the phrenic nerves
C3-C5
C3, C4, C5 keeps the diaphragm alive
while at rest where it its highest point
T9
inferior where if the diaphragm attached with the body wall
at level T12
where is the blood supply to the diaphragm from and where does it drain into
blood supply from the intercostal arteries
venous drainage is to the inferior vena cava
what 3 major structures travel through the diaphragm
the aorta
the inferior vena cava
the oesophagus
what does contraction of the diaphragm do to it
flattens it increasing the volume of the thorax and aids inspiration
in addition what directions do the ribs move
up and outwards
where are the intercostal muscles located
in between the ribs
which type of intercostal muscles are more superficial
external intercostal muscles
where do they get blood from and where does it drain into
from the intercostal arteries
drains into the intercostal veins
what are they innervated by
the intercostal nerves
what is the intercostal neurovascular bundle
the intercostal artery, vein and nerve travelling together in the intercostal space lying at the lower border of each rib
what do the external intercostal muscles do
pull the ribs upwards and forwards during inspiration
what do the internal intercostal muscles do
pull the ribs down and inwards during active respiration
what is the vascular tree composed of
arteries, veins and capillaries which takes deoxygenated blood to the lungs and returns oxygenated blood to the heart
what is the airway tree consist of
air wat filled branching tubes originating from the trachea that take new air to the gas exchange surface and return used air to the environment
what is pulmonary oedema
build up of fluid in the interstitial space in the lungs, this increases the diffusion distance of gases between the blood and alveoli (leads to hypoxia)
The trachea is the single widest of the conducting airways, however it has the smallest
cross sectional area therefore is responsible for most of the airway resistance
what prevents the trachea from collapsing
rings of hyaline cartilage surrounding it
where does the bifurication of the trachea into two bronchi occur
level T4
why is level T4 important
It is the level of the sternal angle (angle between the manubrium and body of the sternum)
It is the level where the trachea bifurcate into the two main bronchi
It is the level of the arch of the aorta
It is where the second rib articulates with the sternum
at about the 12th division of the bronchi what can be found
brochioles
alveoli are arranged in what…
lung lobules
what are lung lobules
cluster of alveoli surrounded by elastic fibres and a network of capillaries
what is the apical surface of the alveoli covered in
surfactant
histology of upper respiratory tract:
the nasal cavity and sinuses has a large SA, why
to warm and moisten inhaled air
the nasal cavity is lined with what epithelium
pseudostratified columnar epithelium
what do the columnar cells have on their surface
cilia
what other cells does the epithelium contain to secrete mucous
goblet cells
histology of the lower respiratory tract:
the bronchial tree is lined with what type of epithelium in the larger bronchi
respiratory type epithelium
what epithelium and the bronchioles lined with
simple ciliated columnar epithelium and goblet cells are sparse
what is the respiratory bronchioles lined with
cuboidal ciliated epithelium
what are the alveolar ducts lined with
flattened epithelium
what cells does the alveoli consist of
type I and II pneumocytes
alveolar macrophages
the alveolar wall contains lots of
elastin
type I pneumocytes are very thin allowing what
gaseous diffusion
pneumocytes are flattened cells with flattened nuclei and are joined together by what
tight junctions
what do type II pneumocytes secrete
surfactant
these cells are round and contain mitochondria.
what does surfactant do
acts as a detergent reducing alveolar surface tension preventing the collapse of the alveoli during expiration and facilitating inspirational expansion
