7. Respiratory system Flashcards
what type of tissue holds open the larynx and trachea
Hyaline cartilage
what tissue bridges the gap between the free ends of C-shaped cartilages in the trachea?
smooth muscle
what is present within the walls of bronchi but not bronchioles?
cartilage
where is Reinke’s space?
in the vocal cords
which cells secrete surfactant?
type II pneumocytes
what cells are phagocytes
alveolar macrophages
how many cell layers are there in the air blood barrier
2
how thick is the air-blood barrier
600nm
where are the pores of Kohn
alveolar walls
respiratory epithelium
lines tubular portion of the respiratory
Pseudostratified
ciliated
interspaced goblet cells
the nose
filtration, humidification, warming, olfaction
keratinising and non-keratinising squamous epithelium
respiratory epithelium
richly vascular lamina propria containing seromucinous glands
the nose - olfaction
roof of nasal cavity, extending down septum and lateral wall
Pseudostratified columnar epithelium of olfactory receptor cells with supporting sustentacular cells and basal cells
serous glands of Bowman
Non-motile cilia
olfactory receptor cells
bipolar neurones - dendrite extends to surface to become club-shaped ciliated olfactory vesicle
nasopharynx
gas transport, humidification, warming, olfaction, lined by respiratory epithelium
nasal sinuses
lower the weight of the skull, add resonance to the voice, humidify and warm inspired air, lined by respiratory epithelium
the larynx
cartilaginous box (hyaline), voice production, respiratory epithelium, loose fibrocollagenous stroma with seromucinous glands, lymphatics and blood vessels common
the vocal cords
voice production
stratified squamous epithelium overlying irregular fibrous tissue (Reinke’s space)
almost no lymphatics
tranchea
respiratory epithelium
seromucinous glands in submucosa
trachealis muscle posteriorly
C-shaped (hyaline) cartilagenous rings
clara cells
most numerous in terminal bronchioles
mitochondria, smooth ER, secretary granules
no cilia; vesicular cytoplasm
precise purpose is uncertain, think they produce and eliminate surfactant and oxidise inhaled toxins
respiratory bronchioles
first part of distal respiratory tract link terminal bronchioles and alveolar ducts cuboidal ciliated epithelium spirally arranged smooth muscle no cartilage
alveoli
150-400 million/lung
250 um in diameter
type I pneumocytes
40% of cell population
90% of surface area
flattened cells, flattened nucleus, few organelles
type II pneumocytes
60% of cell population
5-10% of surface area
rounded cells, rounded nucleus, rich in mitochondra, smooth and rough ER, spherical bodies
produce surfactant
alveolar macrophages
luminal cells, also present in the interstitium
phagocytose particles including dusts and bacteria
enter lymphatics or leave via mucocilary esculator
blood-air barrier
type I pneumocyte
fused basement membrane of penumocyte and capillary
vascular endothelial cell
200-800nm thick
interstitium
where endothelial cells are not in direct contact with pneumocytes collagen and alastin fibres fibroblasts macrophages (pore of Kohn)
Visceral pleura
flat mesothelial cells loose fibrocollagenous connective tissue irregular external elastic layer interstitial fibrocollagenous layer irregular internal elastic layer
