Respiratory System Histology (Shaw) - W2 Flashcards
What are the components of the respiratory division?
- respiratory bronchioles
- alveolar ducts
- alveolar sacs
- alvoeli
What cells are found in the non-olfactory regions of the nasal cavity?
- respiratory epithelium: pseudostratified ciliated columnar epithelium
- lamina propria
- glands
- lymphoid elements, plasma cells
What cells are found in the olfactory region of the nasal cavity?
-
olfactory cells
- bipolar neurons w/nucleus in middle of cell
-
sustentacular cells
- columnar cells that provide physical support, nourishment and electrical insulation
-
basal cells
- pyramidal cells that do not reach epithelial surace - reservoir for replacing other cells
What are the functions of the nasal cavity?
- filter by trapping in bed of mucus
- warm and humidifying
- antigen and allergen monitoring
- IgE and IgA
where is the pharynx found and what epithelium makes it up?
- found from choanae to opening of larynx
- superior nasopharynx - has respiratory epithelium
- oropharynx (middle) and layrngeal pharynx (inferior) have stratified squamous epithelium
Where is the larynx and what type of cartilages does it have?
- between pharynx and trachea
- cartilage
- hyaline
- elastic
what are the two folds in the larynx?
- vestibular folds - superior position, immovable, pseudostratified ciliated columnar epithelium
- vocal folds - dense, regular elastic connective tissue - regulates the width of the space between the vocal folds
What types of epithelium cover and what makes up the epiglottis?
- core is elastic cartilage
- superior surface has stratified squamous epithelium
- inferior surface has pseudostratified ciliated columnar epithelium
What reinforces the trachea?
10-12 C shaped cartilaginous rings - made up of hyaline cartilage that is joined by smooth muscle
What are the 3 layers of the trachea?
- mucosa
- respiratory epithelium
- Submucosa
- Cartilaginous
- Adventitia
What are the cell types in the respiratory epithelium of teh trachea?
- ciliated columnar cells - move mucus
- goblet cells - mucus secretion
- basal cells - replenish other cells
- kulchitsky cells - replenish other cells
- brush cells - short columnar, receptors
What are the trends as the airways go down the bronchial tree?
- decreasing cartilage, glands, goblet cells and height of epithelial cells
- increasing amounts of smooth muscle and elastic tissues
How are secondary bronchi different from primary bronchi?
- made up of pseudostratified ciliated columnar epithelium
- C shape cartilage is replaced by irregular hyaline cartilage
- all round - no flat.
- seromucous glands and lymphoid elements are present
What makes up larger vs smaller bronchioles?
- larger bronchioles - ciliated simple columnar w/occasional goblet cells
- smaller bronchioles - simple cuboidal w/occasional Clara cells
explain the division of the bronchial tree
trachea –> main bronchus –> seocondary bronchus –> bronchioles –> terminal bronchioles –> respiratory bronchioles –> alveolar ducts, alveolar sacs, and alveoli
What do Clara cells do?
- columnar cells - dome shaped pieces w/short microvilli
- numerous secretory granules
- protect bronchiolar epithelium
- degrade inhaled toxins via C-P450 enzymes in membranes of smooth ER
- surfactant production
What is found in the terminal bronchioles?
Club (clara cells) and cuboidal cells
What is found in the respiratory bronchioles that wasnt found in the terminal bronchioles?
- wall has occasional alveoli where gas can be exchanged.
- as the respiratory bronchioles get smaller, there are more alveoli
describe the alveolar ducts
do not really have walls - are more linear
intraalveolar septa reinforce the alveolar ducts
What makes up type I pneumocytes, how much surface do they cover
- made up of simple squamous epithelial cells
- covers about 85% of the alveolar surface
- slightly fewer in number than type II pneumocytes
what are type II pneumocytes made of?
- cuboidal in shape - more dome like
- cover 5% of alveolar surface
- more numerous than type I
- lamellar bodies that contain surfactant are present
what are the components found in surfactant
- dipalmitoyl phosphatidylcholine and phosphatidylglyercol
parasympatehtic nerve supply
comes from vagus - causes bronchoconstriction
What is shown below?
Respiratory olfactory epithelium
you can see pseudostratified columnar epithlium with Bowman’s glands.
What is shown below?
- Trachea
- contains
- EL = elastic lamina
- E - pseudostratified ciliated columnar epithelium
- SM = submucosa
What is shown below?
Trachea
-
Mucosa
- has elastic lamina
- psuedostratified ciliated epithelium that rests on thick basement membrane (arrows)
- Submucosa
- has many glands
*
- has many glands
What is shown below?
Trachea epithelium
Numerous goblet cells (G) inserted into the epithelium as unicellular glands produce a mucus that coats the ciliated epithelial surface. The intense-staining dark band (BB) at the apical ends of the ciliated cells is due to the presence of large numbers of basal bodies that are responsible for cilia formation. The epithelium sits on a thick basement membrane (BM) and adjacent to the basement membrane is the underlying lamina propria.
What is shown below?
Submucosa of the trachea w/seromucous glands
D= ducts
M=mcuous secreting cells
S = serous secreting cells
What is shown below?
Bronchi
E = pseudostratified columnar epithelium with occasional goblet cells
SM = smooth muscle found around
A = alveoli
C = c-shaped hylaine cartilage that is found
What is shown below?
Bronchi
What is shown below?
Bronchioles
epithelium vaires depending on large or small.
NO GLANDS OR CARTILAGE
What is shown below?
TERMINAL BRONCHIOLE
E = simple low cuboidal epithelium
Some smooth muscle persists in terminal bronchiole wall epithelium
What is shown below?
Respiratory Bronchioles
Alveoli interrupt the epitheium.
No goblet cells or smooth muscle
What is shown below?
Respiratory bronchioles
What is shown below?
Alveolar ducts - as indicated by astericts.
Alveoli are labled with “A”.
VP = visceral pleura w/thin layer of connective tissue
What is shown below?
Alveolar sacs
What is shown below?
Respiratory capillaries
What is illustrated by the arrow?
Type II pneumocytes
What is shown by the arrow?
Thickening of interalveolar septum around alveoli by smooth muscle.
What is shown and what comprises it?
Visceral pleura
made up of connective tissue and mesothelium
Alveoli are immediately adjacent
What is shown? What is the arrow?
Trachea
pseudostratified columnar ciliated epithelium
Where was this taken and what is at the tip of the arrow?
Trachea
hyaline cartilage
What tissue is shown and what is shown by the arrow?
Trachea
seromucous gland.
