Exam I Flashcards
Histo: Where does the cartilage stop?
Bronchioles
-inc. SM, inc. elastic
True/False: Goblet cells, glands and cartilage are not found in the bronchioles, however, SM and elastic fibers are present
True
*SM: diameter
*elastic: expands and contracts
The typical epithelium of the respiratory tract is
- ciliated pseudostratified columnar with goblet cells
- changes at bronchioles: no goblets, no glands, no cartilage
The paranasal sinuses are blind end cavities in the frontal, sphenoid, ehtmoid and maxillary bones. They are lined by respiratory epithelium and drain into the wall of the nasal fossa. These sinuses are considered the
diverticula of the nasal cavity
NOTE: Sinusitis and sinus infections:
- adults: maxillary sinus
- children: ethmoid (halitosis)
The mesothelium + thin layer of CT that covers the lung is known as the _____ pleura. The mesothelium covering the wall of the thoracic cavity is known as the ______ pleura.
Lung: visceral Wall: parietal *serous membranes **90% of mesotheliomas (mesothelial cells - misplace underlying lung alveoli)
The larynx is made up of several cartilages (hyaline and elastic). Extrinsic muscles provide support and movement (deglutition) while intrinsic muscles provide
-phonation and conduit (air flow)
*both are skeletal muscle
The blood-air barrier contains what type of epithelium?
simple squamous
Site where respiration begins
Respiratory bronchioles
Regions of direct air flow have what type of epithelium?
Stratified squamous
Other alveolar cells including endothelial cells, fibroblasts, mast cells, monocytes and macrophages (dust cells) are located in the
interstitium or area between alveolar walls
Neutrophils secrete Elastase which attacks what fibers in the bronchi, bronchioles, alveolar ducts and alveoli?
elastic fibers
Lymphatic nodules in the lamina propria of the bronchioles
BALT
Emphysema is the permanent enlargement of alveoli or air spaces caused by destruction of the alveolar wall. It results from the loss of ____ fibers.
Elastic fibers Results: -thickened vessel walls -accumulate macrophages in alveoli 2 sites: Centriacinar and Panacinar A. Centriacinar: air trapped in respiratory bronchioles B. Panacinar: air trapped in entire resp. unit
Describe the normal epithelial transition in the respiratory portion of the lungs
-ciliated columnar -to ciliated simple cuboidal -to simple squamous
Describe the features of bronchioles
-No cartilage, No glands, -Goblets early -1mm or less in diameter -SM -elastic fibers Terminal portion: Alveoli appear -become respiratory bronchioles
Cystic fibrosis involves production of a defective CFTR (cystic-fibrosis transmembrane conductance regulator), a channel for what ions?
Chloride ions
-CFTR degraded due to defective protein folding
Results:
- decreased Na/C;- reabsorption in sweat glands
- Inc. Na reabsorption (other epithelium) -bronchus, pancreas -Water moves into cells
Differentiate between the conducting portion and the respiratory portion of the lungs
- Conducting -conduction
- hyaline and elastic cartilage
- elastic fibers
- SM (nasal, pharynx, larynx, trachea, bronchi, bronchioles, terminal bronchioles) - Respiratory portion:
- elastic fibers
- SM (respiratory bronchioles, alveolar duct, alveoli)
______ constitute the air passages most often affected in children by measles virus or adenovirus which can cause bronchiolitis (closure of airway due to fibrosis)
Bronchioles
Describe the vascular supply to the pulmonary branches
- Pulmonary artery: deox blood in -travels with conductile and respiratory tree 2. Pulmonary vein: ox blood out -veins: run between septa -Bronchial arteries: taking oxygenated blood to lung tissue (off aorta)
Trachea: True/False: Trachea and Respiratory diverticulum are outgrowths of gut tube
True
Trachea: The trachea is a long tube lined by respiratory epithelium. It has goblet cells, a thick basal lamina and ciliated cells. It is often described as a “ciliary escalator lined by mucous”. The trachea is a part of the ____ portion of the respiratory system
-Conducting portion (inspired and expired air) -16 generations of divisions -continuation from the larynx (inferior limit of cricoid cartilage)
Trachea: List the cells of the trachea
- Ciliated (most common) -sweep mucous -trap dust 2. Basal cells: -base of columnar cells -replace other epithelial cells 3. Goblet (mucous) 4. Brush (receptor cells) -sneeze rflex 5. Small granule (DNES cells) –diffuse neuroendocrine system –hormone secretion (endocrine) –secretory granules (peptide hormones) *cause carcinoid tumors
Nasal cavity: The area/epithelium that is located on the roof of the nasal cavity and medial/lateral nasal wall.
Olfaction area -bipolar neurons (project to olfactory bulb) -CN 1 *pseudostrat. columnar with goblet
Larynx: Below the epiglottis are two pairs of folds: the _____ vocal cords and the ____ vocal cords
- False vocal cord (ventricular folds) 2. True vocal cord (vocal folds) –direct air flow -strat. squamous epithelium -vocalis musscle *reverts back to respiratory epithelium (pseudostratified columnar with cilia and goblet cells) as moves into trachea