Test 4-1 Flashcards
functions onf resp system
air conduction, filtration and gas exchagne
each terminal bronchiole and its respiratory bronchiloar branches supply…
a pulmonary acinus
each respiratory bronchiole supplies a
respiratory bronchiolar unit (aka primary pulmonary lobule)
extrapulmonary airways
- Nasal vestibule and cavity
- Nasopharynx and oropharynx
- Larynx
- Trachea and primary bronchi
intrapulmonary airways
- Secondary (lobar) bronchi
- Tertiary (segmental) bronchi undergo approximately 20 successive divisions. The smallest and last branch is the terminal bronchus.
- terminal bronchus gives rise to primary (lobular) bronchioles.
- Each terminal bronchiole and its respiratory bronchiolar branches supply a pulmonary acinus.
respiratory airways
- Each respiratory bronchiole supplies a respiratory bronchiolar unit (aka primary pulmonary lobule).
- Alveolar ducts
- Alveolar sacs
- Alveoli
brionchiole (lobular) supplies:
secondary pulmonary lobule
terminal bronchiole supplies:
pulmonary acinus
respiratory bronchioles supplyL
primary pulmonary lobule (respiratory lobule)
anthracosis
shows secondary pulmonary outlines - macrophages have eaten carbon ad move into the lymphatics which run in the septa… can see each secondary pulmonary outline
olfactory epithelium epithelium and residents
-pseudostratified columnar w/ cilia
- olfactory receptor cells: axons penetrate the lamina propria and basal lamina; unmyelinated and w/ its own special supporting cell=??
- sustenacular cells: columnar, support and nourish the bipolar receptor cells; lipofuscin granules present
- brush cells: strited brush border; sensory; CN V
- basal cells: short pyramidal shaped on basement membrane; stem cell population that turns into other 3 cells times
larynx epithelium
- stratified squamous non keratinized - subject to vibration and abraision - epglottis and over true vocal chord
- pseudostrat columnar w/ goblet cells - below epiglottis to false to start of true vocal chord and then below true vocal fold down
glands in false vocal folds are:
seromucous glands - mucous durp. - lubrication of lining
reinkes space:
is that part of the lamina propria lying between the basal lamina and the vocal ligament.
edema accumulates in this space
lamina propria of olfactory epithelium contains
- bowman’s glands-serus product contains odorant binding protein
- unmyelinated nerve fibers and bundles
- swell bodies:
psuedostratified epithelium of larynx is also called and is important for:
respiratory epith and mucociliary clearance
vocal folds, anterior surface of epiglottis, and exterior laryngeal surfaces are covered by
non-keratinized, stratified squamous epithelium.
vocal ligament is found
in the lamina propria overlying the vocalis muscle of the true vocal cord
Cellular epithelial residents of the airways are
- Diverse in the larger airways; less diverse in the small airways
- Nonepithelial cells may also be found – Mast cells and intraepithelial lymphocytes (mainly T cells) in larger airways
wall layers of trachae and primary bronhcus
- mucosa
- submucosa with glands
- cartiallage (and treachealis)
- adventitia
wall layers of intrapulmonary bronhci
- mucosa
- muscularis
- submucosa with glands
- cartilage
- adventitia
wall layers of bronchioles
- mucosa
- muscularis
- fibroelastic CT layer
layers of the trachae and extrapulmonary bronchi
1) mucosa
2) submucosa
3) cartilage
4) adventitia
mucosa of trachae and extrapulmonary bronchi
1) Respiratory epithelium supported by a prominent basement membrane
- Ciliated columnar cells are the drivers of mucociliary clearance
- Goblet cells extend from the trachea) to the small bronchi; normally absent in small bronchioles.
- Goblet cells increase in number and extend into the bronchioles when irritated.
- Brush cells have microvilli and have a sensory receptor function
- Basal cells are regenerative cells
- Neuroendocrine cells (of Kulchitsky) – are most numerous in fetal lungs then decrease substantially after birth. Proliferate in certain diseases of the pulmonary system.
- Intraepithelial lymphocytes (mainly T cells)
- Mast cells
2) Lamina propria
submucosa of trachae and extrapulmonary bronchi
- Connective tissue is slightly denser than the lamina propria
- Contains seromucous glands that are responsible for secreting mucins, bacteriostatic substances lactoferrin and lysozyme, IgA produced by plasma cells, and protease inhibitors (e.g., α1-antitrypsin) to degrade proteases released by leukocytes.
A deficiency of α1-antitrypsin leads to
the development of a form of emphysema. (submucosa of trachea/extraplmo branches
cartilage of trachae and extrapulmonary bronchi
- C-shaped rings of hyaline cartilage in the trachea and primary (extrapulmonary) bronchi. -Smooth muscle bridges the ends of the rings.
- Intrapulmonary bronchi contain discontinuous plates of cartilage
adventitia of trachae and extrapulmonary bronchi
fourth layer.
layers of intrapulmonary bronchi
- –> Mucosa – layer 1
- Epithelial cell height decreases as bronchi divide and become smaller
- Basement membrane becomes less conspicuous until it is no longer discernable with a light microscope
- Lamina propria
—> Muscularis of smooth muscle is a new layer – layer 2
- —>Submucosa – layer 3
- Cartilage exists as plates or islands – layer 4
—->Adventitia – layer 5
Asthma and chronic bronchitis
- cause remodeling of the walls of bronchi and bronchioles
- increased mucous production**
- Basal lamina becomes thicker**
- Edema and inflammation of the wall= inc in lamina propria thickness **
- Leukocytes are numerous.
- inc in thickness of muscularis**
- increase in glands of submucosa**
- Hypertrophy and hyperplasia of submucosal glands and goblet cells are more numerous
- Hypertrophy and hyperplasia of smooth muscle cells
layers of bronchioles
1) Mucosa
2) Smooth muscle
3) Fibroelastic CT layer - Elastic fibers maintain the patency of bronchioles - keep from collapsing
- submucosa, submucosal glands, and cartilage are absent in bronchioles
mucosa of bronchioles (terminal)
1) Cellular residents of epithelium rest on a basal lamina:
- Respiratory epithelium in large bronchioles. The epithelium progressively diminishes in height and is simple cuboidal in respiratory bronchioles. The cells are ciliated, though some of the cuboidal cells are non-ciliated.
- Goblet cells are present in large bronchioles; absent in small bronchioles. Goblet cells increase in number and extend into smaller bronchioles with chronic irritation.
- Club (Clara) cells are present in terminal and respiratory bronchioles.Secrete surfactant (differs in chemical composition from that of type II alveolar cells); produce club cell protein (CC 16). CC 16 is increased in the blood and decreased in bronchoalveolar lavage fluid when bronchioles are damaged. CC 16 is an antioxidant/anti-inflammatory molecule. Club cells also regulate Cl- transport. Club cells divide to replace bronchiolar and alveolar epithelial cells.
- Brush cells and neuroendocrine are present in small numbers
2) Lamina propria – glands are absent
what cells secrete surfactant and what layer of what?
club cells in mucosa of bronchioles
goblet cells are present in what and absent in what?
present in large bronchioles
absent in small bronchioles
histology of respiratory surface:
Delicate thin-walled alveoli are associated with respiratory bronchioles, alveolar ducts, and alveolar sacs
-alveolar cells - epithelial type I & II; alveolar macrohages;
alveolar epithelial cells :
1) Type I alveolar cells (pneumocytes)
- represent about 40% of the epithelial cell population but line over 90% of the alveolar surface area
- THIN Simple squamous cells that are attenuated to facilitate gaseous diffusion between blood and alveolus. Type I cells are connected to one another by tight junctions.
- Not capable of cell division
2) Type II alveolar cells (pneumocytes)
- More numerous than type I cells (about 60% of the population) but contribute less than 10% of the alveolar surface area
- ABLE TO DIVIDE in to type I and II
- PLUMP Cuboidal cells with short apical microvilli and connected to type I cells by tight junctions.
- lamellar bodies that contain its secretory product, pulmonary surfactant. Surfactant is composed principally of the phospholipids, dipalmitoyl phosphatidylcholine and phosphatidylglycerol and four surfactant proteins (A, B, C, and D).
3) brush cells
Surfactant
- produced by type II epithelial cells 20-22 weeks
- continuously produced as it is turned over by the endocytotic action of type II pneumocytes and alveolar macrophages via reseptor mediated endocytosis
inducer of surfactant synthesis
cortisol - for respiratory distress syndrome in premautre babies
Inadequate surfactant production causes the lungs to
collapse (atelectasis)
inhibitor of corticosterioids=
insulin
-hyperinsulinemia in fetuses of diabetic mothers leads to a higher incidence of respiratory distress syndrome.
Alveolar macrophages (dust cells)
- Found in the alveolar lumen and migrate over the epithelial surface.
- Also found in the connective tissue compartment of the interalveolar septum.
- Most migrate into the ciliated portions of the airways where they are eliminated by mucociliary clearance
- Some migrate to the connective tissue of the lung beneath the visceral pleura. Black speckled appearance.
- Activated macrophages release proteases that are normally kept in check by antiproteases (e.g., α1-antitrypsin). Genetic deficiency of α1-antitrypsin leads to a form of emphysema.
- Heart failure cells - macrophages that eat RBC and are full of hemosiderin bound to iron
Interalveolar septum
1) Space between adjacent alveolar epithelium
2) Contains continuous capillary or, in wider areas, type III collagen and elastic fibers.
3) Blood-gas barrier
- Type I pneumocytes with adluminal surfactant
- Fused basal laminae of type I pneumocyte and continuous capillary
- Endothelial cells of continuous capillary
three types of bronchioles in order…
lobular bronchiole (goblet cells) —> terminal bronchile —> respiratory bronchioles (no goblet cells)
club cells foudn in
terminal and respiratory bronchioles
if damage to bronchiole epithelial =
increase in CC16 protein
3 mucosa of oral cavity
masticatory - abrasive area
lining
specialized
masticatory muscoa
1) Located on gingivae and hard palate
2) Keratinized and parakeratinized stratified squamous epithelium
3) Lacks a submucosa on gingivae (gums) and palatine raphe
4) Submucosa is found on hard palate: \
a) Anterior submucosa contains adipose CT
b) Posterior submucosa contains mucous glands
c) Collagen fibers anchor mucosa to periosteum of hard palate
5) Burton’s line – blue-gray gingival margin due to lead poisoning
lining mucosa
- Most of oral cavity is lined by this type
- Nonkeratinized stratified squamous (may be parakeratinized in some locations-WITH NUCLEUS): Stratum basale; Stratum spinosum; Stratum superficiale
- Submucosa: Present except on inferior surface of tongue; Contains minor salivary glands and collagen and elastic fibers
Specialized mucosa
associated with taste (gustation)
tongue surface components
1) Filiform: Smallest and most numerous; Elongated, conical projections of connective tissue covered by keratinized stratified squamous epithelium; Only type of papilla to lack taste buds
2) Fungiform: Mushroom-shaped projections covered by stratified squamous epithelium with taste buds; More abundant at tip of tongue
3) Circumvallate; Eight to twelve large papillae surrounded by a moat located anterior to sulcus terminales; Taste buds are located in the stratified squamous epithelium; Lingual salivary glands (von Ebner’s glands) empty their serous secretions into the moat’s base
4) Foliate: Covered by stratified squamous epithelium with taste buds and located along lateral sides of tongue; Small serous glands empty into clefts
taste buds
-Taste pore=Three cell types:
A) Neuroepithelial (sensory) cells
1. Apical surface contains microvilli. Tastants bind to a taste receptor (TR 1 or TR 2). The TR1/2 is associated with a G protein complex called gustducin. The alpha subunit activates GTP which results in depolarization. The influx of Ca ions causes release of neurotransmitters.
2. Connected to neighboring cells via tight junctions and form synapses with CN VII, IX and X
3. Turnover every 10 days
B) Supporting cells:
1. Contains microvilli and tight junctions but do not form synapses
2. Turnover every 10 days
C) Basal cells are located near basal lamina and serve as stem cells
three regions define the lip:
skin, vermilion zone, and mucosa
skin of lip
stratified squamous, keratinized epithelium with hair follicles and glands (sweat and sebaceous). Dermis lies deep to epithelium
vermilion zone of lip (red free margin)
- thin skin that allow the redness of blood to be visible.
- Lacks hair follicles and sweat glands
mucosa of lip
- wet stratified squamous, nonkeratinized epithelium with a lamina propria.
- submucosa lies deep to the mucosa and contains labial salivary glands
major salivary glands
parotid
submandibular
sublingual
parotid gland
- Compound acinar gland
- Purely serous ****
submandibular gland
- Compound tubulo-acinar gland
- Mixed (serous and mucous) though serous predominant****
- Serous demilunes are present
sublingual gland
- Compound tubulo-acinar gland
- Mixed though mucous predominant**
- Serous demilunes are present
[aquired] pellicle is
protective coat on teach made up of proteins in saliva
Layers of a tooth
1) Enamel (covers anatomic crown; absent at root)
2) Dentin (present in crown and root)
3) Cementum (covers root; absent at anatomic crown)
4) Pulp cavity in center w/ nerves and BV
anatomic crown=enamel and dentin
root = cementum and dentin