Biol 432 PP Respiratory System
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Transcript of Biol 432 PP Respiratory System
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RESPIRATORYRESPIRATORYRESPIRATORYRESPIRATORYRESPIRATORYRESPIRATORYRESPIRATORYRESPIRATORY
SYSTEMSYSTEMSYSTEMSYSTEMSYSTEMSYSTEMSYSTEMSYSTEM
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RESPIRATORY SYSTEM
nnnn CONDUCTINGPORTION
nnnn RESPIRATORYPORTION
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SKELETAL MUSCLES AND BONES ARE REQUIRED
FOR RESPIRATORY SYSTEM FUNCTION
STERNUM
INTERCOSTAL MUSCLES
DIAPHRAGM
RIBS
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GENERAL ORGANIZATIONAL PATTERN OF CONDUCTING PORTION OF RESPIRATORY SYSTEM
���� MUCOSALuminal sheet epithelium(typically “respiratory epithelium”)Lamina propria (loose FECT)
���� SUBMUCOSA (mod. dense FECT)(not always present or merged
with lamina propria, serous or mixed glands maybe present in the lamina propria or submucosa)
���� “MUSCULARIS” EXTERNA (may be smoothmuscle, cartilage, or bone)
���� ADVENTITIA or SEROSA (absent in nasal cavity)
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CELL TYPES FOUND IN
“RESPIRATORY EPITHELIUM”
PREDOMINANT CELL TYPES
���� Ciliated columnar cells – move
mucus
���� Goblet cells – secrete mucus
���� Basal cells – replace damaged cells
LESS COMMON CELL TYPES
���� Brush cells – sensory receptor cells
���� Dense core granule cells (Small granulecells) – enteroendocrine cells
���� Clara cells (trachea and bronchi) – protein
secreting cells, secrete surfactant
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PREDOMINANT CELL TYPES
FOUND IN “RESPIRATORY EPITHELIUM”
Source: Lentz. 1971. Cell Fine Structure.
Ciliated columnar cell Goblet cell (Mucous cell)
Basal cell
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“RESPIRATORY EPITHELIUM”
Source: Weiss. 1983. Histology. Cell and Tissue Biology. 5th Edition.
Ciliated cells
Goblet cell/
Mucous cell
Basal cell
Brush
cells
Small granule cell
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(surfactant)
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“RESPIRATORY” EPITHELIUM
Cilia
Basement membrane
Goblet cells
Ciliated cells
Small
granule
cellBasal cell
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EPITHELIA OF REGIONS WITHIN
NASAL CAVITIES
���� VESTIBULE orNOSTRIL Stratified squamous
sheet epithelium
���� RESPIRATORY SEGMENT
”Respiratory
epithelium”
���� OLFACTORY SEGMENT Olfactory
epithelium
RESPIRATORY SEGMENT
OLFACTORY SEGMENT
NOSTRIL
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NASAL CAVITIES/ NASAL PASSAGEWAYS
Source: Plate 88, Figure 1 in Ross et al. 1995. Histology. A Text and Atlas. 3rd Edition.
OEp = olfactory
epithelium
OM = olfactory
mucosa
Rep = “respiratory
epithelium”
EB = bone
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CELL TYPES FOUND IN
OLFACTORY EPITHELIUM
nnnn Sustentacular orsupporting cells
nnnn Olfactory cells
nnnn Basal cells
nnnn Brush cells
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Mucosa of the Olfactory Segment
of the Nasal Cavity
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Mucosa of the Olfactory Segment
of the Nasal Cavity
Source: Plate 88, Figure 2 in Ross et al. 1995. Histology. A Text and Atlas. 3rd Edition.
SC = supportive
cells
OC = olfactory
neuron cell bodies
BC = basal cells
BG = olfactory
glands (serous)
N = peripheral
nerves
V = blood vessels
C = capillaries
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NASAL CAVITIES/NASAL PASSAGEWAYS
are separated from oral cavity by PALATE
RESPIRATORY SEGMENT
OLFACTORY SEGMENT
NOSTRIL
Modified from: Figure 18.1 in Ross et al. 1995. Histology. A Text and Atlas. 3rd Edition.
HARD PALATE SOFT PALATE
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SOFT PALATE
Source: Hammersen. 1980. Histology.
“Respiratory epithelium”
of Nasal Mucosa
ORAL CAVITY
side
NASAL CAVITY
side
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PHARYNX
”Respiratoryepithelium”
Stratified squamoussheet epithelium
Modified from: Figure 18.1 in Ross et al. 2003. Histology. A Text and Atlas. 4th Edition.
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RESPIRATORY SYSTEM
nnnn NASAL CAVITIES/ NASAL PASSAGEWAYS
n PHARYNX -nasopharynx, oropharynx
n LARYNX
n TRACHEA
n EXTRAPULMONARYBRONCHI
n LUNGS
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LARYNX and TRACHEA
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
Food
cartilage
cartilage
cartilage
bone
Surface View Mid-longitudinal Section
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EPIGLOTTIS of LARYNX
Source: Hammersen. 1980. Histology. A Color Atlas of Cytology, Histology and Microscopic Anatomy. 2nd Edition.
Stratified squamous
epithelium
Elastic Cartilage
Stratified squamousor pseudostratified
columnar epithelium
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LARYNX
Source: Hammersen. 1980. Histology. A Color Atlas of Cytology, Histology and Microscopic Anatomy. 2nd Edition.
Ventricular fold/
false vocal cord
Vocal fold/
true vocal cord
Epiglottis
Stratified squamous
sheet epithelium
Pseudostratified ciliated
columnar sheet epithelium
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LARYNX
Source: Hammersen. 1980. Histology. A Color Atlas of Cytology, Histology and Microscopic Anatomy. 2nd Edition.
Intrinsic glands in
Lamina propria of
Mucosa
Vocalis muscle
Epiglottis
Vocal ligament
Cartilaginous plate in
“Muscularis” Externa
Striated skeletal
muscle tissue in
“Muscularis” Externa
Cartilaginous plate in
“Muscularis” Externa
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RESPIRATORY SYSTEM
nnnn NASAL CAVITIES/ NASAL PASSAGEWAYS
n PHARYNX -nasopharynx, oropharynx
n LARYNX
n TRACHEA
n EXTRAPULMONARYBRONCHI
n LUNGS
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Trachea
���� Mucosa“Respiratory” epithelium (+/- Clara cells)Lamina propria of loose FECT
���� SubmucosaLoose to moderately denseFECT,
denser than lamina propria, may contain compound tubuloacinar glands
���� “Muscularis”externaHyaline cartilages (horseshoe-shaped “rings”)Smooth muscle across open ends of cartilagesModerately dense FECT connects adjacent rings
���� AdventitiaLoose FECT
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TRACHEA
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
Adventitia “Muscularis”
Externa
(trachealis muscle)
Mucosa
luminal
epithelium
in submucosa
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TRACHEA
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TRACHEA
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Cilia
Basement membrane
Goblet cells
Ciliated cells
Small
granule
cellBasal cell
LUMINAL EPITHELIUM OF TRACHEA
(“Respiratory” Epithelium)
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RESPIRATORY SYSTEM
nnnn NASAL CAVITIES/ NASAL PASSAGEWAYS
n PHARYNX -nasopharynx, oropharynx
n LARYNX
n TRACHEA
n EXTRAPULMONARYBRONCHI
n LUNGS
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Bronchus (very similar to Trachea)
���� Mucosa“Respiratory” epithelium (+/- Clara cells)Lamina propria of loose FECT
���� SubmucosaLoose to moderately denseFECT,
denser than lamina propria, may contain compound tubuloacinar glands
���� “Muscularis”externaHyaline cartilages (horseshoe-shaped “rings”)Smooth muscle across open ends of cartilagesModerately dense FECT connects adjacent rings
���� AdventitiaLoose FECT
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RESPIRATORY SYSTEM
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
PULMONARY LOBULE
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ORGANIZATION OF LUNG
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
3-9 = intrapulmonary bronchi
10 = large bronchiole
tb = terminal bronchiole
rb = respiratory bronchiole
ad = alveolar duct
as = alveolar sac
a = alveolus
l = lobule
PULMONARY LOBULE
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HISTOLOGICAL FEATURES OF PULMONARY COMPONENTS
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ORGANIZATION OF LUNG
Source: Gartner & Hiatt. 1994. Color Atlas of Histology. 2nd Edition.
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ORGANIZATION OF LUNG
Source: Freeman & Bracegirdle. 1976. An Advanced Atlas of Histology.
alveoli
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ORGANIZATION OF LUNG
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
3-9 = intrapulmonary bronchi
PULMONARY LOBULE
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Intrapulmonary Bronchi���� Mucosa
“Respiratory” epithelium (+/- Clara cells)Lamina propria of loose FECT
���� “Muscularis”Spiral bundles of smooth muscle
���� SubmucosaLoose to occasionally moderately dense FECT,may contain compound tubuloacinar glands
���� “Muscularis”externaHyaline cartilages (horseshoe-shaped “rings”)Smooth muscle across open ends of cartilagesModerately dense FECT connects adjacent rings
���� AdventitiaLoose FECT
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INTRAPULMONARY BRONCHUS
Source: Jungueira et al. 1975. Basic Histology. 4th Edition.
Mucosa
Intrinsic glands in
Lamina Propria
FECT
Cartilaginous plate in
“Muscularis” Externa
Bronchiole
branching off
of bronchus
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Hyaline Cartilage
Smooth Muscle
Loose FECT
Pseudostratified Columnar Epithelium
An Intrapulmonary Bronchus
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BRONCHIOLES
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
PULMONARY LOBULE
���� MUCOSALuminal sheet epithelium (ranges from pseudostratifiedciliated columnar in largebronchioles to simplecuboidal with mixed ciliatedand Clara cells in terminalbronchioles)Lamina propria = loose FECT
����“MUSCULARIS” = bundles of smooth muscle
<1 mm in diameter
No cartilage in wall
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TYPES OF BRONCHIOLES
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
10 = large bronchiole
tb = terminal bronchiole
rb = respiratory bronchiole
nnnn LARGE BRONCHIOLESPseudostratified ciliated columnar
sheet epithelium to simple columnarsheet epithelium
nnnn TERMINAL BRONCHIOLESMainly simple cuboidal sheetepithelium
nnnn RESPIRATORY BRONCHIOLESSimple cuboidal sheet epithelium
(mainly Clara cells)
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CELL TYPES FOUND IN
LUMINAL EPITHELIUM OF BRONCHIOLES
nnnn Ciliated cells
nnnn Basal cells
nnnn Goblet cells
nnnn Brush cells
nnnn Small granule cells
nnnn Clara cells
Source: Ross et al. 1995. Histology. A Text and Atlas. 3rd Edition.
Clara cell Ciliated cellCiliated cell
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BRONCHIOLE
Source: Burkitt et al. 1993. Wheater’s Functional Histology. A Text and Colour Atlas.
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Alveoli are where
the action is (at
least in terms of
gas exchange)
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ORGANIZATION OF LUNG
Source: Freeman & Bracegirdle. 1976. An Advanced Atlas of Histology.
alveoli
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ALVEOLI or AIR SPACES
AS = alveolar sacA = alveolus
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ALVEOLI (AIR SPACES)
Source: Leeson & Leeson. 1981. Histology. 4th Edition.
ad = alveolar duct
as = alveolar sac
a = alveolus
Occur in the walls of
���� Respiratory bronchioles
���� Alveolar ducts
���� Alveolar sacs
CONSIST OF:
���� Alveolar Epithelium
���� Thin region of highly vascularized FECT
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CELL TYPES FOUND IN
ALVEOLAR EPITHELIUM
nType I Pneumocytes [gas exchange]
nType II Pneumocytes [secrete
surfactant (mix of proteins and lipids)]
nBrush Cells [sensory receptors]
nPulmonary Macrophages
[phagocytosis]
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CELL TYPES FOUND IN
ALVEOLAR EPITHELIUM(as observed at TEM level)
Source: Lentz. 1971. Cell Fine Structure.
Type I Pneumocyte(and adjacent capillary)
Type II Pneumocyte
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Alveolar Wall Structure – Type I Cells
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Alveoli
Lung Injected to Show CapillariesCapillaries (red structures)
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ALVEOLI ARE SITES
OF GAS EXCHANGE
AIR
RBC
BLOODBLOOD
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Alveolar Wall Structure –Type II or
Great Alveolar Cells
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CELL TYPES
FOUND IN
ALVEOLI(as observed at the LM level)
In addition to Type I and Type II alveolar cells
(pneumocytes), macrophages
are frequently observed migrating along the alveolar
surface. Macrophages are frequently detached from the
surface during processing.
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Criteria for Classifying Intrapulmonary Structures
Structure Lining Epithelium Other Features
Bronchi pseudostratified hyaline cartilage in wallcolumnar usually + smooth muscle
Bronchioles pseudostratified no hyaline cartilage in wallcolumnar to smooth muscle presentsimple cuboidal,no squamous
Respiratory >50% cuboidal or little or no smooth muscle,Bronchioles columnar, <50% usually some loose FECT
squamous (butsquamous present)
Alveolar Ducts <50% cuboidal, no smooth muscle, looseAlveolar Sacs >50% squamous FECT sparse or absent
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ALVEOLI & BRONCHIOLES
TB = terminal bronchioleRB = respiratory bronchioleAD = alveolar ductAS = alveolar sac