Histology Flashcards
Portions of Respiratory System
-Conducting portion
-Respiratory portion
What is the extend of the conducting zone
(From the nasal cavity to terminal bronchioles)
Notes:
Nasal cavity, nasopharynx, larynx, trachea, intrapulmonary bronchus, terminal bronchioles
What is the extend of respiratory zone
From the respiratory bronchioles to alveoli
How many types of pneumocytes in the respiratory systems?
2 (type I and type II)
What are the type of tissue of pneumocyte type I and the function
-simple squamous epithelium
-thus it allows the gas exchange
What are the type of tissue of pneumocyte type II and the functions
-cuboidal and granular epithelium
-thus it allows secretion of surfactant
-and it allows regeneration
Type of tissue in conducting zone
Pseudostratified ciliated columnar epithelium with goblet cell
Types of cells in respiratory epithelium
-ciliated columnar
-goblet cell
-brush cell
-basal cell
-endocrine cell
The most abundant type of cell in respiratory epithelium
Ciliated columnar cells
The most abundant type of cell in respiratory epithelium
Ciliated columnar cells
Describe the apical structure of the ciliated columnar
-it has apical cilia
-with mitochondria underneath it
-to provide energy for ciliary movement
Fate in case of failure of ciliary movement of the ciliated columnar cell
Chronic Respiratory Infection
What is the shape and content of apical portion of the goblet cell
-wide
-mucinogen granules
What is the shape and content of basal portion of the goblet cell
-narrow
-nucleus and organelles
Functions of goblet cells
-it secretes mucous
-this provides protective mechanism as trapping
-it prevents dehydration
What is the content of apical portion of the brush cell?
Microvilli
What is the content of basal portion of the brush cell?
Afferent Nerve Endings
What is the content of basal portion of the basal cell?
Afferent Nerve Endings
Functions of brush cells
it acts as a chemosensory receptor
Where does the basal cells lie
it lies on basal lamina
What is the shape of basal cells
-short
-it does not reach the luminal surface
Function of basal cells and what is the characteristic that aids it
-it acts as a stem cell
-because it is mitotically active
Where does the endocrine cells lie
It lies on the basal lamina
What is the content of the basal portion of the endocrine cells
Dense granules
Functions of endocrine cells
-it secretes hormones (aminopeptides)
-it acts as the integration of mucous and serous
Functions of endocrine cells
-it secretes hormones (aminopeptides)
-it acts as the integration of mucous and serous
What is the structure that supports the lungs?
-hyaline cartilage
-about 16-20 in numbers
What are the components of the mucosal layer of the trachea
-epithelium
-lamina propria
-elastic membrane
The respiratory epithelium of the trachea lies on ___ basal lamina
A. Thick
B. Thin
Thick
What is the function of the elastic membrane of the mucosa of the trachea
-to separate between lamina propria and submucosa
What are the contents of the submucosa of the trachea
-seromucous glands
-lymph follicles
What is the structure that fills the gap between c-shaped hyaline cartilage in the supporting layer
it is a smooth muscle called trachialis muscle
What are the changes that occur to the epithelium as it reaches distally
-pseudostratified columnar ciliated
-simple columnar ciliated
-simple cuboidal partially ciliated (at the terminal bronchioles)
NOTE: ciliated cells continue until the termination of goblet cells to prevent accumulation of mucous
What are the changes that occur to the goblet cells as it reaches distally
it decreases in number and replaced with clara cells in the bronchioles
What is the histological structure of the extrapulmonary bronchus
same with trachea
In mucosal layer of bronchus, what differs it from trachea
-respiratory epithelium will decrease in size and the goblet cell will decrease in number
-no elastic membrane
What is absent in the mucosal layer of bronchus
elastic membrane
What is the content of the submucosa of the bronchus and how it is arranged
-layers of smooth muscles
-arranged spirally
What is the contents of the supportive layer of the bronchus
-hyaline plates
-seromucous glands and lymph follicles
List down the layers of the bronchioles
-mucosa
-musculosa
-connective tissue layer
Describe the mucosal layer of the bronchioles
-simple cuboidal epithelium partially ciliated
-disappearance of goblet cells which replaced by clara cells
Describe the mucosal layer of the bronchioles
-simple cuboidal epithelium partially ciliated
-disappearance of goblet cells which replaced by clara cells
What are the structures that are absent in the bronchioles
Notes: Bronchioles has O in it so always NO
(No goblet cell, no cartilage, no glands, no lymph follicles)
What are the components of the respiratory portion
-respiratory bronchioles
-alveolar duct
-alveolar sac
-alveoli
Characters of alveoli
-pocket-like
-thin layer with extensive capillary beds
Characters of alveoli
-pocket-like
-thin layer with extensive capillary beds
“Wall of neighbouring alveoli”
This refers as
Interalveolar septum
What presents in the cytoplasm of the pneumocyte type 1
-pinocytotic
-but free of organelles
NOTES; the organelles are grouped around the nucleus
How does the pneumocytes connected to each other
-tight junction
-desmosome
list down the layers of blood-air barriers
-surfactant of alveolar
-cytoplasm of pneumocytes type 1
-the fused basal laminae of pneumocytes type 1
-endothelial layers
What are the structure that responsible to give foamy appearance if pneumocytes type II
lamella bodies
