5- Respiratory Histology Flashcards
What is considered the Conducting Portion of the respiratory pathway?
Nasal Cavity Paranasal Sinuses Nasopharynx Trachea Primary, Secondary, Tertiary Bronchi Bronchioles and Terminal Bronchioles
The function of the Conducting Portion is to do what?
Warm, filter, and humidify the air
Transmit to the respiratory portion
***If the air stays cold and dry it can damage the lung tissue!
T/F. There is NO gas exchange in the Conducting Portion.
True. It is considered “Anatomic Dead Space”
What is considered the Respiratory Portion of the respiratory pathway?
Respiratory Bronchioles
Alveolar Ducts
Alveolar Sacs
What is the function of the Respiratory Portion?
Pass air to alveoli for gas exchange
This is a short passage for air between the pharynx and trachea.
Larynx
The wall of the Larynx is reinforced by _______ cartilage (Thyroid and Cricoid cartilages) and smaller ________ cartilages.
Hyaline
Elastic
The Larynx contains the True Vocal folds/cords, which is lined with what type of epithelium?
Nonkeratinized Stratified Squamous Epithelium
***Protects mucosa from abrasions
The free edge of the vocal folds is supported by what?
Vocal Ligament (Elastic CT)
This muscle allows the movement of the vocal folds.
Vocalis M.
The Trachea to the Segmental Bronchi contain what tissue structures?
Epithelium Goblet Cells Ciliated Cells Glands Hyaline Cartilage Smooth Muscle Elastic Fibers
The Bronchioles, Terminal Bronchioles, and Respiratory Bronchioles contain what tissue structures?
Epithelium
Ciliated Cells
Smooth Muscle
Elastic Fibers
The Alveolar Duct, Alveolar Sacs, and Alveoli contain what tissue structures?
Epithelium
Elastic Fibers
The Respiratory Epithelium is unique to the respiratory tract and is composed of…
Pseudostratified Ciliated Columnar Epithelium
What is the function of respiratory epithelium (Pseudostratified Ciliated Columnar Epithelium)?
Protect airway via mucus production
Transport mucus up and out of respiratory tract via cilia
What other types of cells are present in the respiratory epithelium?
Ciliated Cells
Goblet Cells
Basal Cells
These are mitotically active stem cells within the respiratory epithelium.
Basal Cells
This lies underneath the respiratory epithelium and has a rich vascular network with complex capillary loops.
Lamina Propria
These are modified columnar epithelial cells that synthesize and secrete mucus.
Goblet Cells
Goblet Cells have apical cytoplasm that contains a dense aggregation of ________ ________. These are released by exocytosis and combine with water to form ________.
Mucigen Granules
Mucus
The base of the Goblet Cell is occupied by a _______ ______ and crammed with organelles.
Basal Nucleus
This is a short, flexible tube that serves as a conduit for air. It connects the larynx to the main/primary bronchi.
Trachea
This is what keeps the lumen of the Trachea open.
Cartilaginous Rings
The Trachea consists of four layers, which are…
Mucosa
Submucosa
Cartilaginous Layer
Adventitia
This layer of the Trachea is composed of respiratory epithelium with an elastic, fiber-rich Lamina Propria. Has numerous Goblet Cells and BALT (Bronchi Associated Lymphoid Tissue).
Mucosa
This layer of the Trachea is composed of a slightly denser CT than Lamina Propria.
Submucosa
***Rich in Submucosal Glands
This layer of the Trachea is composed of C-shaped hyaline cartilage rings.
Cartilaginous Layer
This layer of the Trachea is composed of the Trachealis M. and CT that binds the Trachea to adjacent structures.
Adventitia
***Has few Submucosal Glands
Bronchi are defined as being > ____ mm (if smaller then they have become Bronchioles).
1
What are the 4 layers of Bronchi?
Epithelia
Submucosa
Muscularis
Adventitia
This layer of the Bronchi is composed of Pseudostratified Ciliated Columnar cells that are shorter in height. It has fewer Goblet Cells and increased elastic fibers in the Lamina Propria.
Epithelia
This layer of Bronchi is composed of loose/areolar CT and has few submucosal glands. Full cartilage rings transition to irregular cartilage plates.
Submucosa
This layer of Bronchi is continuous in larger Bronchi and is loosely organized in smaller Bronchi.
Muscularis
This layer of Bronchi is moderately dense CT.
Adventitia
These have a diameter < 1 mm after approx. 10 generations of branching, and only consist of an epithelia and muscularis layer.
Bronchioles
T/F. Bronchioles are no longer composed of respiratory epithelium.
True
Epithelia for large bronchioles contain what cell type?
Simple Ciliated Columnar
Epithelia for small bronchioles contain what cell type?
Simple Cuboidal
The epithelia for bronchioles contain few goblet cells and _______ cells, as well as increased elastic fibers.
Club
The muscularis layer for Bronchioles is composed of prominent…
Smooth Muscle
The Bronchioles have no _________ plates.
Cartilage
These are the final part of the Conducting Portion.
Terminal Bronchioles
Terminal Bronchioles contain these non-ciliated, dome-shaped cells.
Club Cells
***Formerly called Clara cells
Club cells secrete a _________ that prevents luminal adhesion with airway collapse during expiration.
Lipoprotein
Club cells can also ________ inhaled materials and secrete _________ peptides.
Detoxify
Antimicrobial
Terminal Bronchioles consist of an epithelial and muscularis layer. What are each of these layers made of?
Epithelia = Simple Cuboidal with Club cells and increased elastic fibers
Muscularis = 1-2 layers of Smooth Muscle
This is the first part of the Respiratory Portion and its mucosa contains openings to Alveoli, which is where gas exchange occurs.
Respiratory Bronchioles
Respiratory Bronchioles consist of an epithelial and muscularis layer. What are each of these layers made of?
Epithelia = Simple Cuboidal with Club cells and elastic fibers
Muscularis = Smooth Muscle
What do Respiratory Bronchioles branch into?
Alveolar Ducts — Alveolar Sacs — Alveoli
Alveolar Ducts end in ________ ________, which consists of 2 or more clusters of Alveoli.
Alveolar Sacs
These are aggregates of smooth muscle, collagen, and elastic fibers that form around Alveolar Ducts.
Alveolar Rings
What type of epithelia are Alveoli composed of?
Simple Squamous
Alveoli and blind-ended sacs that are lined with _________. They are composed of Simple Squamous epithelium, supporting tissue, and blood vessels.
Pneumocytes (Type I and II)
This is the term for the small openings that permit movement of air between Alveoli.
Alveolar Pore
This type of Pneumocyte is squamous (flat) and lines almost the entire alveolar surface. It creates a surface for gas exchange and is closely associated with capillaries.
Type I
This type of Pneumocyte is cuboidal/rounded and secrete surfactant via exocytosis, which reduces surface tension within alveoli and prevents collapse during respiration.
Type II
***These are the precursor for both Type I and II
Lungs are lined by a serous membrane, called the _______ and _______ pleurae.
Parietal
Visceral
This pleura lines the internal cavity wall.
Parietal Pleura
***Outside of balloon
This pleura lines the organ (lungs).
Visceral Pleura
***Outside of fist
The Parietal and Visceral Pleurae are separated by the _______ _______ which contains serous fluid.
Pleural Cavity
This is the term for the simple squamous epithelium that is flattened and covers the pleurae.
Mesothelium
- **Also lines peritoneum and pericardium
- **Mesothelioma is a tumor of this
The Parietal and Visceral Pleurae have underlying fibrous tissues of _______ and _______ fibers. It extends into the lung as fibrous septa, and it continuous with _______ _______. Contains extensive lymphatic vessels.
Collagen
Elastic
Lung Parenchyma
The air in the alveoli and blood in the capillary, called the Blood-Air Barrier, are separated by 3 components, which are…
Alveolar epithelium (2-3 highly attenuated, thin cells lining the alveolus – Type I Pneumoctyes)
Fused Basal Laminae of the alveolar epithelium and capillary endothelium
Capillary endothelial cells
This is a chronic inflammatory disease involving the airways and is from a sudden constriction of smooth muscle in the Bronchioles (Bronchospasm).
Asthma
Asthma occurs from an infiltration of the Bronchial wall by what cells?
Eosinophils
Lymphocytes
Mast Cells
In asthmatic people, there is a thick Bronchiolar epithelium with an increased number of ________ cells, a thick basement membrane, and hyperplastic _______ ______ cells.
Goblet
Smooth Muscle
This is caused by a permanent enlargement of air spaces distal to the Terminal Bronchiole. There is chronic obstruction of airflow due to the narrowing of Bronchioles and is accompanied by the destruction of the Alveolar walls.
Emphysema
Emphysema causes a significant loss of _______ _______ due to the decrease in surface area.
Gas exchange
What can cause emphysema?
Smoking cigarettes
Chronic inhalation of particulate material (i.e., Coal dust, Construction dust)
Genetic predisposition (Autoimmune)
This causes an inflammation of the lung tissue and the air spaces are filled with exudate containing WBCs (mainly neutrophils), RBCs, and fibrin.
Pneumonia
The lung of a person with pneumonia can go through a “red hepatization stage” where the tissue looks like _______.
Liver
Pneumonia causes enlarged capillaries, congested with _______. On gross examination the lung appears red, firm due to lack of ______ _____, and heavy due to the presence of _______.
RBCs
Air spaces
Exudate
