Respiratory system microscopy Flashcards
epiglottis
composed of elastic cartilage, covered by non cornified stratified squamous because this surface is subject to abration during swallowing of food bolus
larynx
voice box, the type of epithelium that lines the larynx is respiratory epithelium (ciliated pseudostratified columnar with goblet cells), the part of the epiglottis that is on the side of the airway is only in contact with air
The glands located between the epithelium and cartilages of the larynx (mucous, serous, mixed)- its MIXED
Trachea
respiratory epithelium lines the lumen of the trachea
C shaped rings with a band of smooth muscle, the basement membrane deep to the tracheal epithelium, the cartilage is made of hyaline cartilage, the muscle that closes the C is the trachealis muscle. The muscle contracts when you need increased force of air, like coughing.
The tissue in the submucosa bettween the tracheal epithelium and cartilage is mucous and seromucous glands
Chronic bronchitis
Hypertrophy of the mucous producing glands founds in the submucosa of the large cartilaginous airways, such as the trachea
The management of acute respiratory failure consists of 2 simultaneous processes, maintaining acceptable levels of oxygenation and ventilation, and treatment of infection/removal of secretion/reversal of airway constrictions
COPD as a result of bronchitis who is coughing up sputum, the patient should be urged to cough, a suction catheter. patients cough reflex, in addition to bronchodilation, beta2 adrenergic agents increase the rate of particle transport by ciliated epithelium to improve clearance
Alveolar sac/ alveoli
Alveolar sac is a cluster of alveoli that open into a common air space, the cell types in the walls of an alveolar sac (type 1 and type 2 pneumocytes, alveolar macrophages)
The type of connective tissue that supports the walls of an alveolar sac, is elastic tissue
The passive recoil of elastic fibers in the lungs contributes to exhalation
An alveolar duct is an elongated air passage in which the walls are composed of adjacent alveoli, the ducts are composed of type 1 and type 2 pneumocytes supported by reticular fibers, smooth muscle cells are located at the opening of each alveolus- a sphincter, regulating alveolar air movements
Respiratory bronchioles
The epithelium of alveoli, alveolar sacs and alveolar ducts is highly attenuated simple squamous epithelium
The epithelium of respiratory bronchioles are lined by cuboidal epithelium, they also contain alveoli envaginating their walls, openings have smooth muscles to regulate airflow,
within the epithelium of all bronchioles are club cells, can be distinguised on electron micrographs by lack of ling cilia, functions of club cells secreting material which protects bronchiolar epithelium, degrading inhaled toxins, and serving as stem cells
Terminal bronchiole
charcterized by one or 2 complete layers of smooth muscle cells supporting a cuboidal epithelium, terminal bronchioles do not have alveoli in their walls, they are the distal part of the conducting portion of the respiratory system
Bronchioles are lined by columnar or respiratory epithelium, smooth muscle supports their wall, upon stimulation of the sympathetic division of the autonomic nervous system, the smooth muscle fibers relax to produce bronchodilation
The smooth muscle fibers of blood vessels vasoconstrict
Alveolar wall
Type 1 pneumocytes line most of the surface of the alveoli, but are very flat and hard to identify, type 2, have round nuclie and bulge out, alveolar macrophages are large cells with abundant basophillic cytoplasm and euchromatic nuclei
Normally surfactant coats the surface of the alveoli, which are made by type 2 pneumocytes, the morphologic components of the blood gas barrier are type 1 pneumocytes (fused basal laminae of type 1 pneumocytes and capillary endothelial cells, capillary endothelial cells,, erythrocyte plasma membrane
