Histo Block I: resp sys- gen characteristic, olfactory/respiratory epithelium Flashcards
What are the primary functions of the respiratory system?
1.Air conduction
2.Air Filtration
3.Gas exchange (respiration)
What are the secondary functions of the respiratory system?
*Conditioning the air: Warming air, moistening and removal of particulate materials
*Defense (lymphocytes)
*Role in speech production
What are the 2 portions of the respiratory system?
conducting portion and a respiratory portion
What does the conducting portion of the respiratory system consists of ?
- Passages outside the lung
-Nasal cavities and the oral cavity
-Nasopharynx and oropharynx
-Larynx
-Trachea
-Primary bronchi (pair) - Inside the lung
-The bronchi undergoes extensive branching to form the bronchial tree
In what portion does the gas exchange occur?
respiratory portion
What are the components of the respiratory portion?
1.Respiratory bronchioles
2.Alveolar ducts
3.Alveolar sacs
4.Alveoli
Which are the structural basis for gas exchange?
Blood vessels enter the lung with bronchi. The arteries branch to form capillaries that come into very close contact with the alveoli.
What are the nasal cavities?
Pair chambers separated by a bony and cartilaginous septum
which are the 3 segments of the nasal cavity?
–Vestibule
–Respiratory segment
–Olfactory segment
what is the classification of the epithelium of the vestibule?
The vestibule is lined with epit. strat. squamous a continuation to the skin.
Whta type of secretions are in the vestibule and what are vibrissae?
Mucous and serous secretions.
Short stiff hairs called vibrissae entrap large particulate matter.
What is the epithelium of the respiratory segments of nasal cavity?
Lined with pseudostratified columnar ciliated epithelium with goblet cells. The lamina propria is attached to the bone by the periosteum
WHat are some functions of the respiratory segment of the nasal cavity and wha cell are present?
*Filter, warm and humidify air in normal respiration.
*Production of mucous for protection.
*Respiratory mucosa of the nasal cavity contains cells involved in mucosal immunity. The majority are gamma/delta T lymphocytes.
*Many other cells participating in defense are present in the lamina propria: T lymphocytes, B lymphocytes, neutrophils, macrophages, and mast cells.
WHta components does the lamina PROPIA have?
In the lamina propria abundance of capillaries, venules and small veins in the lamina propria. When have a cold or allergy, vessels leak and tissue swells.
how is the basement membrane and lamina propia in the respiratory epithelium?
A defined basement membrane, and lamina propria very cellular, with many lymphocytes
What is the lymphatic tissue in the respiratory epithelium?
Lymphatic tissue, in both diffuse and nodules is present. This lymphatic tissue is functionally similar to the bronchus-associated lymphatic tissue (BALT).
Identify
Photomicrograph of respiratory epithelium. Showing ciliated columnar cells, mucus-secreting goblet cells and basal cells.
What are the 5 types of cells present in the respiratory epithelium?
- Ciliated cells
- Goblet cells
- Brush cells
- Small granule cells (Kulchitsky cells)
- Basal cells
Which cells of the respiratory epithelium are the most identified, prominent and what is their function?
ciliated cells; tall columnar cells with
cilia that project into the mucus covering
the surface of the epithelium. They are the
most abundant cells (up to 70%).
function of goblet cells
synthesize and secrete mucus (5% to 15% present); increase if epithelium is exposed to irritating substances
function of brush cells
cells with short, blunt
microvilli. Are chemosensory receptor cells
connected to sensory nerve fibers.
function of small granule cells?
contain secretory granules; they are endocrine cells of the diffuse neuroendocrine system (DNES); their function is not clear
function of basal cells
are stem cells, on top of the
basement membrane and have no contact
with the epithelial surface; give origin to other cells in the epithelium
identify
Respiratory epithelium, pseudostratified ciliated epithelium with goblet cells. (H&E) lamina propria with many blood vessel
identify
This electron micrograph shows the three main cell
types of this respiratory epithelium:
1) ciliated epithelial cells extending to the surface, where they possess cilia
2) goblet cells with mucinogen granules
3) basal cells, which are confined to the basal portion of the epithelial layer near the connective tissue.
identify
Olfactory Epithelium and Respiratory Epithelium
The olfactory mucosa (OM), adjacent ethmoid bone (EB) is directly attached to the bone tissue; no
submucosa is present. In this specimen, however, the mucosa is separated from the bone tissue because of
shrinkage, a frequently encountered artifact. The olfactory epithelium (OEp) is pseudostratified, like
respiratory epithelium; however, it is typically thicker. Note the respiratory epithelium (REp) included in the
lower right of the micrograph. The feature that is most useful in identifying olfactory mucosa is the presence of numerous large, unmyelinated nerves (N) and extensive olfactory (Bowman’s) glands (BG) in the
connective tissue of the mucosa. Occasional blood vessels (i.e., arteries [A] and veins