Resp System Histology Flashcards
resp system functions
supply O2 to blood for delivery to cells throughout body
remove CO2 that has been accumulated in the blood from tissues of body
phonation
olfaction
lung function in B.P. control via renin-angiotension system
air to lungs
series of conducting pathways
air enters nose/mouse - pharnynx + larynx - trachea - principal bronchi -
lungs - bronchus - smaller bronchi - bronchiles - alveolar sacs
where does gas exchange occur
alveolar sacs
nasal cavity roles
warming
moistening
filtering inspired air
what does the root of the nasal cavity contain
olfactory epithelium
epithelial lining
vestibule - keratinised stratified squamous epithelium
deeper - keratin = lost
deeper again = epithelium
what lies under resp epithelium
lamina propia
band of loose connective tissue containing seromucous glands + thin walled venous sinuses
thin walled venous sinuses can
quickly engorge with blood + block nose
what is lined by non-keratinized stratified squamous epithelium and why
oropharynx, anterior surface + upper part of posterior surface of epiglottis
oropharynx transmits both air + food
walls of larynx make up
cartilage + muscles
resp epithelium lining its surface
vocal cords + adjacent structures are covered with what
stratified squamous epithelium
trachea is continuous with what
larynx
trachea contains how many cartilages
15-20 C shaped cartialages
opening of C shaped cartilage spanned by
fibroelastic tissue + smooth muscle
trachea lining
respiratory epithelium basal lamina lamina propria submucosa seromuccous glands
trachea divides into
2 main bronchi
walls of bronchus made up od
resp epithelium
lamina propia
muscularis
= ring of smooth muscle + submucossa + adipose tissue + seromuccous glands
bronchial tree
bronchi branch = smaller cartillage = more discontinuous = airway 1mm in diameter = bronchioles
bronchioles
less than 1mm in diameter
lack cartilage
few goblet cells
what is the lamina propria composed of
smooth muscle + elastic + collagen fibres
terminal bronchioles
smallest bronchioles
lack resp function
smooth muscle of bronchioles
respond to parasympathetic innervation
histamine
other factors
contracting + constricting bronchiole diameter
smooth muscle of bronchioles plays a key role in what
asthma
allergic reaction
terminal bronchioles are lined with
cuboidal ciliated epitheliu
what do terminal bronchioles contain
non-ciliated club cells
roles of club cells
stem cells
detoxification
immune modulation
surfactant production
what interrupts continuity of resp bronchioles
alveoli
conducting bronchioles
trachea - terminal bronchioles
no exchange of O2/CO2 with blood
gas exchange occurs where
alveoli (honeycomb shape)
alveoli are lined by
type 1 alveolar cells
type 2 alveolar cells
type 1 alveolar cells
simple squamous epithelium
line alveolar surfaces
barrier of minimal thickness
permeable to gases
type 2 alveolar cells
lamellar bodies contain surfactant
surfactant - spreads over pulmonary surface - reduce surface tension + air fluid interface
reduces - tendency for alveoli to collapse - end of expiration
alveolar macrophages
free cells in septa or migrating over luminal surfaces
septa between alveoli
permeated by capillary networks
air-blood barrier
thin tissue
type 1 cell
visceral pleur
multi-layered
outer layer = mesothelium = simple squamous epithelium
backed by = layers of fibrous + elastic connective tissue
between = pleural cavity = small amount of lubricating fluid
