Respiratory System Flashcards
Upper respiratory tract
this is the nose and the nasal cavity
Lower respiratory tract
(trachea) and within the lungs, the bronchi, bronchioles, and alveoli
Pulmonary plexus
where the autonomic fibers entering the thoracic cavity intersect
tracheal cartilages
c shaped portions of hyaline cartilage around the outside to support the trachea
trachealis muscle
an elastic ligament and band of smooth muscle that connect the open ends of each tracheal cartilage
- this can contract to decrease the lumen of the trachea if something gets in and we start coughing
carina
this is where the trachea divides into the two bronchi
apex
the superior tip of each lung
-just posterior and superior to the clavicle+
costal surface
- this is a curve on the lung
- it curves anterior
- comes in contact with inner contours of the ribcage
mediastinal surface
this contains the hilum
- these have grooves marking the great vessels and the heart
- this is slightly concave and this is on the side where the two lungs face each other
cardiac notch
- an indentation on the left the lung
cardiac impression
a recess formed on the anteroinferior mediastinal surfaces of both lung
oblique fissure
separates the superior and inferior lobes
superior lobes
this is the upper most lobe of each lung
inferior lobe
the most inferior lobe of the lungs
horizontal fissure
- this separates the superior and middle lobe of the right lung
middle lobe
this is the middle lobe on the right lung
hilum
where structures such as blood vessels and nerves enter the lungs
- a groove on the mediastinal surface of the lung
root of lung
this is a meshwork of connective tissue that anchors all of these structures (bronchi, pulmonary vessels, and nerves) to the lung at the hilum
Alveolar type I cells
squamous epithelial cells that are unusually thin and allow gas diffusion
Alveolar type II cells
scattered throughout the type I and they release surfactant
alveolar macrophages
these roam and patrol the epithelial surface and engulf any particles that have eluded other defenses
- these are the last line of defense in the lungs
pulmonary surfactant
an oily secretion containing phospholipids and proteins; acts to keep the alveoli open by reducing surface tension of water molecules and preventing collapse
alveolar sac
this is a group of alveoli
alveolar duct
tiny ducts that connect the respiratory bronchioles to alveolar sacs
respiratory bronchioles
- the final division of the bronchioles within the lung
- simple cuboidal epithelium and contain a thin layer of smooth muscle and elastic fibers
terminal bronchioles
- most distal segment of the conducting zone
- Each of the terminal bronchioles divides to form respiratory bronchioles
- simple cuboidal epithelium
- branch off segmental bronchi
bronchioles
the smaller branches of the bronchial airways in the respiratory tract. They include the terminal bronchioles, and finally the respiratory bronchioles
lobar bronchi
- secondary bronchi
- first subdivision of the main bronchi
- lined by cartilage rings
- conducting airway
bronchi
-primary bronchi
The large air passages that lead from the trachea to the lungs.
-the right division is wider and shorter (more likely to have something lodged into it
conducting portion
- serve to conduct, clean, warm, and moisten the air
- nose, pharynx, larynx, trachea, bronchi, and bronchioles
- anywhere where the exchange of gas is not occurring (this is majority of the structures)
respiratory portion
- respiratory bronchioles, alveolar ducts, alveolar sacs and alveoli
- arrangement allows for a fast efficient transfer of oxygen and carbon dioxide between the blood and the air
- this is basically anywhere we are exchanging gas
pulmonary circulation
the portion of the circulatory system which carries deoxygenated blood away from the right ventricle, to the lungs, and returns oxygenated blood to the left atrium and ventricle of the heart
bronchial circulation
the systemic vascular supply to the lung, and it supplies blood to conducting airways down to the level of the terminal bronchioles as well as nerves, lymph nodes, visceral pleura, and the walls of large pulmonary vessels
inhalation
- breathing air in
- diaphragm and the internal intercostals are responsible for allowing this to happen
exhalation
this is a passive process that occurs from the relaxation of the diaphragm and the internal intercostals
forced inhalation
- uses the diaphragm and the external intercostals just like normal inspiration
- also uses the serratus posterior superior and then a series of other muscles that are recruited
forced exhalation
-requires the recruitment of muscles
-recruits the internal intercostals
-transversus thoracis
-serratus posterior inferior
These all work together to decompress the thoracic cavity along with the relaxation of the other two
external intercostals
this elevates the ribs with inhalation
- this is the most external of the muscles
- innervated by the intercostal nerve
serratus posterior superior
- elevates the ribs with forced inhalation
- these are at the superior end of the ribs on the dorsal side and they begin medially and move laterally inferior until they reach the ribs
- innervated by intercostal nerves
serratus posterior inferior
depress the ribs with forced exhalation
- these are at the inferior end of the ribs on the dorsal side and they start medially and move laterally superior until they reach the bottom ribs
- innervated by intercostal nerves
internal intercostals
this depresses the ribs with forced exhalation
- innervated by the intercostal nerve
transversus thoracis
this is deep to the thoracic cage
- this is the inner most intercostal
- these are recruited for forceful expiration and depresses the ribs
- innervated by intercostal nerves
diaphragm
expands and increases the vertical dimension of the thoracic cavity
- this increases pressure in the abdominopelvic cavity
- this is a thin muscle
- contraction causes it to flatten out which increases the space in the thoracic cavity
- innervated by the phrenic nerve
bronchopulmonary segments
- these are sections of the lungs, there at about 10 in each lung (the left lung can have some fuse which means that lung has 8 or 9)
- a portion of lung supplied by a specific segmental bronchus and arteries.
- These arteries branch from the pulmonary and bronchial arteries, and run together through the center of the segment
alveoli
where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out
respiratory membrane
- membrane separating air within the alveoli from the blood within pulmonary capillaries
- very thin
- consists of the alveolar wall, the capillary wall, and their fused basement membranes
when do type two cells begin producing surfactant
this is between week 16-26
- after this begins respiration is able to occur
- a big reason why a premie baby isn’t able to survive
when do lungs stop developing
lungs develop until early adulthood
-important not to smoke!
functions of the respiratory system
- breathing (ventilation) (provides area for gas exhange)
- gas conditioning
- sound production/verbal communication
- olfaction (smelling)
- defense
gas conditioning
this is our body turning the air humid and warm and preparing it to come into our lungs
-warms it
-cleans it
filters it
respiratory epithelium
pseudostratified ciliated columnar cells
- this lines most of the respiratory tract and then adapts when it needs to because Structure governs function
what cells are in the pharynx
stratified squamous cells
cystic fibrosis
- a thickened mucus occurs in the respiratory tract
- causes the cilia to not do their job and the mucus ends up collecting all this stuff (pathogens, particles, etc)
- this causes neutrophils to come to the area (more so than the normal amount which creates an inflammatory area and it gets harder for air to pass through
how does mucus act as a defense in the respiratory tract
- it physically traps things (pathogens, foreign things)
- it is produced by the cells and the glands
what do nose hairs do for us
they are a form of defense
-they prevent things from getting into the nose
what do the cilia do?
they transport the mucus with the trapped particles to the pharynx where it can either be swallowed for it could spit it out
**essentially just trying to get it away form the respiratory tract
alveolar macrophages
these are found in the alveoli and they are the last line of defense in the respiratory tract
pulmonary arteries
these carry deoxygenated blood into the pulmonary circulation
pulmonary veins
these carry oxygenated blood back to the heart from the pulmonary circulation
left lung
- slightly smaller than right because of the hearts position
- has a cardiac impression and a cardiac notch
right lung
- this has three lobes and is slightly bigger than the left because it doesn’t need to make room for the heart but is slightly shorter due to the livers position
asthma
- a bronchial disease
- inflammatory disease that leads to spasms and difficulty breathing
- hypersensitivity to irritants and allergins
- overtime there are permanent changes to the airways
what causes an asthma attack
this is contraction of bronchiole smooth muscle
-an excessive secretion of mucus is in the airways
segmental bronchi
tertiary bronchi
-these are the ones that branch into each lung segment
(these segments are what are dividing each of the lobes)
what are changes in CT as you move down the bronchial tree
- the c shaped rings are replaces with cartilage plates which get replaced with nothing
- this is important because you need the lungs to be elastic
what are changes in epithelium as you move down the bronchial tree
- initially it is pseudo-stratified ciliated columnar
- this gets replaced by simple columnar, simple cubodial and then simple squamous
- need this to occur for the best possible diffusion at the alveoli
why is smooth muscle important in the bronchial tree
- this is important because contraction allows constriction/dilation of pathway which is very important in stressful situations
what is the importance of pores in the alveoli
these allow for the distribution of air through the alveoli so that the first ones don’t just get all the air and rupture from the pressure
what controls the larynx, trachea, bronchial tree, and lungs
the autonomic nervous system
-sympathetic and parasympathetic fibers form the pulmonary plexus
visceral pleaura
tightly adheres to the outside of the lungs, including within fissures
parietal pleura
this lines the thoracic wall
-receives innervation from the phrenic nerve and the intercostal nerve
(does recognize pain)
pleural cavity
space between the two layers
-receives innervation form the intercostal nerves and the phrenic nerve (allows for recognizing when there is damage by feeling pain)
contraction of the diaphragm does:
- flattens the diaphragm
- expands and increases the vertical dimension of the thoracic cavity
- increases pressure in the abdominopelvic cavity
what is the direction of movement when you breath
- just be able to recognize that there are multiple directions of movement
(-rib cage elevates and depresses
-the diaphragm changes vertically
-the sternum moves posteriorly and anteriorly)
mediastinum
- the central compartment of the thoracic cavity between the two pulmonary cavities
- divided into two parts (inferior, superior)
inferior mediastinum
divided into anterior, middle and posterior
transverse thoracic plane
this is the line that divides the superior and inferior mediastinum compartments
- this starts at the sternal angle to T4-T5
superior mediastinum
contains the
- thymus
- great vessels
- vagus and phrenic nerves
- trachea
- esophagus
anterior mediastinum
- this is between the pericardium and sternum
- contains loose CT, fat, lymphatic vessels and some vasculature
middle mediastinum
contains heart, roots of great vessels, and pericardium
posterior mediastinum
- posterior to the pericardium and the diaphragm
- contains the thoracic aorta, esophagus, veins, lymphatic tissues, nerves( vagus, phrenic, and thoracic sympathetic trunk)
