Week 5 lecture his Flashcards
RESPIRATORY EPITHELIUM
Ciliated pseudostratified columnar epithelium (use every word!!)
all resting on the basement membrane but some reach higher, columar cells with cilia
basal cells are stem cells and divide to maintain epithelium
goblet cells unicellular glands that secrete mucous, with the triangular nucleus
electron microscope
lamina propria = loose connective tissue, under the basement membrane
4 cell types (just remember names, don’t need to distinguish them)
1. Ciliated columnar
2. Goblet
3. Brush
4. Basal
goblet cells
- Mucous secretion
- Nucleus at base
- Increase in number during inflammation
no cilia on it, opens up a pore to secrete mucous
brush cells
just know that it exists
* Columnar
* Microvilli
* Hard to identify
basal cells
- Cuboidal
- Stem cells
lamina propria
name for loose connective tissue because it has natural spaces in it
loose connective tissue, very vascular with lots of vessels
very cellular (fibroblasts, lymphocytes,
plasma cells, masts cells…)
4 layers in Respiratory passages
As air passage lumen diameter DECREASES….
….height of epithelium
decreases
….overall wall thickness
decreases
lumen
epithelium
lamina propria
submucosa
adventitia
trachea microscope
c-shaped ring, cartilage is purple
no cartilage between oesophagus and trachea, just soft tissue
submucose
loose connective tissue (like lamina propria)
submucosal glands (sero-mucous) = produce protein and more glands to produce mucous
glands = lobules
pink collagen among the glands
trachealis muscle = no control over it
smoooth muscle between the c shaped ring cartilage in trachea (hyaline cartilage)
adventitia
variable amount of connective tissue
binds trachea to oesophagus & other structures in neck
pleura
covers surface of the lung - visceral pleura
reflects back on itself to form - parietal pleura
space between plerual space
Serosa = simple squamous epithelium facing space + loose connective tissue
staining between layers
serous = bright and colourful
mucous = clear and pale colours
bronchus submucosa
loos connective tissue
smooth muscle layer
submcusoal glands
adipose
hyaline cartilage plates, not continous ring anyhmore
bronchioles layers
Mucosa
Epithelium: columnar or even
cuboidal (not pseudostrafieid anymore)
lamina propria: very thin loose
connective tissue layer
may or may not see cilia
Submucosa
continuous smooth muscle
layer
NO submucosal glands or
cartilage
Adventitia
Not obvious
smokers lung
surface area decreased
lung volume
walls breakdown
alveoli
0.2mm diameter
* ~ 200 million alveoli per adult lung
* Walls of ducts mostly made up of alveoli
surface area covers up an entire tennis court
Macrophages
*Located in the alveolar septum & lumen of alveoli
keeping things clean in alveoli
Type I alveolar cells (40% of cell population)
- Squamous (cover 95% of surface) = realy flat
- Zonula occludens junctions
- Cannot divide
- gaseous exchange occuring
Type II alveolar cells (60%)
- Secrete surfactant maintains suraface tension of alveolus so they don’t stick when you breath out
- Cuboidal (cover only 5% of surface)
- May divide to become type I (if injury occurs)
- walls of alveolus
microscope alveoli
alveolar duct = look like tears, big gaps
septum = divisions between air space, blood vessels in the wall e–> continous capillaries
terminal bronchiole (cartilage, epithlium type, cells, goblet cells, smooth muscle)
no cartilage
simple cuboidal epithelium
some ciliated cells
NO goblet cells
thick layer of smooth muscle
respiratory bronchiole (cartilage, epithlium type, cells, goblet cells, smooth muscle)
no cartilage
simple cuboidal epithelium
very few ciliated cells
NO goblet cells
very little of smooth muscle
alveolus (cartilage, epithlium type, cells, goblet cells, smooth muscle)
no cartilage
simple squamous epithelium
Type 1 and 11 alveolar
NO goblet cells
occasional smooth muscle
