50R. respiratory histology Flashcards
what cells line the nasal cavity
pseudostratified ciliated columnar epithelium
what other cells are within pseudostratified ciliated columnar epithelium (respiratory epithelium) lining the nasal cavity
goblet cells, basal cell, lamina propria/submucosa(connective tissue)
The nasal cavity lined with pseudostratified ciliated columnar epithelium with goblet cells do what to inspired air
warm, moisten and filter
in addition to the roof of the nasal cavity there is a specialised area. what is this.
olfactory epithelium
Underneath the respiratory epithelium (RE) in the Nasal cavity there is the lamina propria, a band of loose connective tissue containing what? ……….(SM) and thin-walled ………..?(V) which can quickly engorge with blood and ‘block’ the nose
seromucous glands
venous sinuses
what is the front part of the nasal cavity called, just inside the nostrils
vestibule
what is the vestibule lined with
keratinized stratified squamous epithelium which then transitions to respiratory epithelium deeper in
what are the 3 types of pharynx
nasopharynx
oropharynx
hypopharynx
what is the oropharynx lined by
non-keratinized stratified squamous epithelium to resist abrasion from food and air
what is the larynx composed of and lined by
cartilage and muscles
lined by respiratory epithelium
the larynx is made up of cartilage and muscles and lined by respiratory epithelium except for what structure
vocal folds
what cells are vocal folds lined with
stratified squamous epithelium
what is epiglottis
cartilage of the larynx
what is in the larynx
ventricular fold, ventricles, vocal fold, vocalis muscle, mucous glands, infraglottic cavity
which vertebrae does the trachea start
C6 just below the cricoid cartilage of the larynx
what type of cartilage is in trachea
C shaped
how many C shaped cartilages in a trachea
15-20
The trachea is continuous with the larynx. When does it terminate
when dividing into the main bronchi
The open side of the ‘C’ of the cartilage in the trachea is spanned by what tissue? and smooth muscle. What muscle?
fibroelastic
trachealis muscle
what lines the trachea
respiritory epithelia backed by basal lamina and lamina propria of connective tissue with lots of elastic fibres and submucosa of connective tissue that has many seromucous glands
the trachea splits into ……?? main bronchi
2
the wall of the bronchus is made from what
respiratory epithelium, lamina propria and some of the cartilage is replaced with muscularis (a ring of smooth muscle) and submucosa with adipose tissue and some seromucous glands
as the bronchi branch becomes smaller the cartilage starts to do what
become more discontinuous and is finally lost when airway is about 1mm in diameter
These smaller airways lacking cartilage are called…..
bronchioles
what else besides cartilage do bronchioles lack
glands
will bronchioles contain many, few or no goblet cells
few
what lines bronchioles
cuboidal epithelial cells
The smallest bronchioles lack respiratory (gas exchange) function are referred to as what
terminal bronchioles
terminal bronchioles give rise to bronchiole that have respiratory function. these are called what?
respiratory bronchioles
The smooth muscle (SM) of the bronchioles respond to …………………innervation, ……………….and other factors by contracting and constricting the diameter of the bronchiole.
parasympathetic and histamine
smooth muscle contraction in the brochioles as a resullt of histamine, parasympathetic innervation and other factors plays a significant role in what reactions
asthma attacks and allergic reactions
terminal bronchioles are lined with what and also contain what cells
cuboidal ciliated epithelium and non ciliated club cells
alveoli are lined with what cells
type I alveolar cells (also called type I pneumocytes)
The respiratory bronchioles are the ………..of the respiratory portion of the airways.
beginning
whats the difference between conducting airways and respiratory airways
Conducting- start from the trachea and go all the way to the terminal bronchioles. These parts just help air travel in and out, but they don’t do any gas exchange (no swapping of oxygen and carbon dioxide with the blood).
Respiratory - The terminal bronchioles lead to respiratory bronchioles, alveolar ducts, and alveolar sacs. This is where the magic happens! The alveoli are where the oxygen gets into your blood and the waste gas (carbon dioxide) gets out.
what are the alveoli and what nature do they make the lungs
terminal portions of the bronchial tree and are responsible for the spongy nature of the lungs.
Nature - Spongy
what do alveoli in histology resemble
honeycomb
Within alveoli oxygen and CO2 are exchanged. There are about …………….. alveoli in each lung.
300 million
alveoli is lined by what
type 1 and 2 alveolar cells (pneumocytes) - simple squamous
the cells in the alveoli provide what barrier
minimal thickness that is permeable to gas exchange
describe type 2 alveolar cells
polygonal shape/ cuboidal
covered in microvilli
lamellar bodies containing surfactant
how is the surfactant released and what does it do/reduce?
The surfactant is released by exocytosis and spreads over the pulmonary surface to reduce the surface tension at the air-fluid interface. This reduces the tendency for the alveoli to collapse at the end of expiration.
what else apart from type 1 and 2 alveolar cells are present in the alveoli
alveolar macrophages (dust cells)
what do the alveolar macrophages (dust cells) do?
phagocytosing inhaled particles that may have escaped entrapment by the mucous lining of the airway.
They typically will migrate up the bronchial tree, transported by ciliary action, to the pharynx where they are swallowed or will move into the septal connective tissue where they will remain.
where can you find alveolar macrophages (dust cells) in the alveoli
free cells either in the SEPTA or migrating over the LUMINAL SURFACES of the alveoli
what is the alveolar wall
the air blood barrier
the septa between alveoli are permeated by what?
capillary networks
The air- blood barrier consists of
the Type I cell,
the endothelial cell and the basal lamina of each.
what is the visceral pleura
a multi layered membrane that covers the lungs
name the layers of the visceral pleura
outer and underlying layers
describe the outer layer of the visceral pleura - whats it made of
simple squamous epithelium called mesothelium backed by layers of fibrous and elastic connective tissue
the visceral pleura would face the parietal pleura which is a similar but generally simpler membrane lining the thoracic cavity. Between the two would be a ………. containing a small amount of lubricating fluid.
pleural cavity
