Respiratory System Flashcards
what are glands formed from and how
formed from covering epithelia
describe exocrine glands
ducts and secretory portions
released on cavities or surfaces
describe endocrine glands
secretory vesicles
becomes separated from epithelium
released directly into circulation
name 2 endocrine glands and describe
pancreas and pituitary - organized into quadrants
thyroid - produces thyrotropin, follicle associated to capillaries
how can glandular epithelial tissue be classified - 5
number of cells
fate of secretion
way the secretory products leave the cell
ducts
secretory portion
describe classification of glands according to number of cells
Unicellular - goblet cell, digestive and respiratory system
multicellular (sweat gland)
describe classification of glands according to number of fate of secretion
exocrine - salivary glands, sweat glands
endocrine - endocrine pancreas
describe classification of glands according to how secretory products leave cell
merocrine - sweat gland = morphologically stays the same
holocrine - sebaceous gland = cell itself, cell death
apocrine - mammary gland = in between holo and mero, big fat globule and is released into secretion
describe classification of glands according to ducts
simple - gastic gland
compound - salivary gland
describe and give examples of simple ducts
simple tubular = gastric gland
simple coiled tubular = sweat gland
simple branched tubular = pyloric glands
simple branched acinar = trachea
describe and give examples of compound ducts
compound tubulo acinar = submandibular gland/salivary
compound tubular =
compound acinar = parotid/sublingual gland, salivary
describe classification of glands according to secretory portion
acinar (secretory portions of round) = mucous (sublingual salivary gland) and serous (parotid gland)
tubular (sweat gland - highly coiled)
what is function of respiratory system
provide oxygen and remove carbon dioxide from blood
name 2 portions of respiratory system
conducting
respiratory
what is a part of conduction portion
nasal cavity
nasopharynx
oropharynx
larynx
trachea
bronchi
bonchioles (regular and terminal)
what is function of conducting portion
warming - so cells like alveolar cells wont get frozen
humidifying
cleaning
Delivery of air - cannot collapse
what does conducting portion posses
Structures to ensure uninterrupted supply of air - cartilage - to keep open, smooth muscles, connective tissue = provides some rigidity, flexibility, extensibility * elastic fibers
glands and ciliated cells to remove foreign particles
what is a part of respiratory portion
respiratory bronchioles
alveolar ducts
alveolar sacs
lung alveoli
what is function of respiratory portion
gas exchange takes place
name layers of general plan of conducting portion - trachea
mucosa
submuocsa
adventitia
describe mucosa of trachea
pseudostratified columnar ciliated epithelium with goblet cells, rests on bm
lamina propria, loose ct, elastic fibers, capillaries, rich in capillary network - warms air
describe submucosa of trachea
denser ct and glands
serous and mucosa acini
hyaline cartilage
trachealis muscle - smooth muscle, gap or opening filled with smooth muscle cells
describe hyaline cartilage in trachea
cricoid cartilage =complete Rings in trachea (below= incomplete)
chondrocytes ring attached by fibrous tissue
describe adventitia of trachea
dense irregular ct - connects and supports
describe serous acinus
small dots at apex of all
bit basophilic towards base
myoepithelial cells between secretory cell and bm
secretes water
provides humidity
describe mucous acinus
nuclei compressed against cell
produces glycoproteins
mucous
coats epithelium
describe serous and mucous acinus secretions
serous = fluid/liquid will evaporate and humidify air
mucous = secrete mucous and glycoproteins to coat
what is respiratory epithelium
pseudostratified ciliated columnar epithelium
with goblet cells
describe goblet cells
Secrete mucous
bulky unicellular glands
doesnt stain well
mucous excreted by exocytosis
what is purpose of cilia
removes dust and particles and stuff
describe cells of respiratory epithelium
brush cells = have microvilli, could be sensory cells or precursors to ciliated cells
short cells - stem cells, no granules
small granule cell = argentaffin/dnes = diffuse neuroendocrine system, cannot see, must be silver nitrate to stain granules
endocrine cell, secretes towards lp
describe goblet cell in greater detail
triangular shape
large golgi complex - adds sugars
RER = protein synthesis and initial glycosylation
becomes glycoprotein packed into secretory granules and released by exocytosis
what is outside and inside cilia
outside = PM
inside = axoneme
describe axoneme
complete microtubule and one incomplete one, looks like C
# of subunits = 13 dots = protofilamnets
13 complete microtubules
9+2 configuration, nine pairs and 2 central
describe microtubule
single microtubule formed by polymerization of alpha and beta tubulin
13 subunits in cross section
9 peripheral, similar to basal bodies - centrioles
wall of single microtubule = 13 protofilaments, alternating alpha tubulin and beta tubulin
what is centriole
very similar to basal body - at right angles almost
what is central sheath of axoneme
around central pair
what is nexin of axoneme
bind all axoneme microtubules
what is radial spokes of axoneme
proteins that join peripheral to central microtubules
what is dyenin arms of axoneme
moves cilia
M2 = incomplete
M1 = complete
what is tectins of axoneme
inside complete microtubule
describe basal body-centriole
protein linker
triplets, M1 = complete, M2 and M3 (not continuous) = incomplete
name 2 mutations that affect axoneme
primary ciliary dyskinesia
radial spoke protein mutations
describe primary ciliary dyskinesia
lack of dynein arms (mutations in genes coding
dynein arms)
Renders Cilia and sperm immotive or dysmotile
impaired mucus clearing (bronchiectasis)
chronic sinusitis
Situs inversus (Kartagener’s syndrome) - 50% of patients (flipped heart & organs)
Male infertility
* tail of spermatozoa contains axonemes
describe radial spoke protein mutations
results in immotile cilia & sperm
Radial spokes are composed of at least 20 other proteins
list pathway of air entering body
trachea
pulmonary bronchus
regular bronchiole
terminal bronchiole
respiratory bronchiole
alveolar duct
alveolar sac
lung alveoli
describe pulmonary bronchus
lumen
epi = respiratory, less goblet cells since structure becomes smaller-they would obstruct
LP = loose ct
capillary network = warms ait
smooth muscle cells - complete layer
pieces of hyaline cartilage - small islands in submucosa, polymorphic
serous acini
adevntitia
folded mucosa
criss cross - looks like complete layer
what are diameters of regular and terminal bronchioles
1-3mm in diameter
describe regular bronchiole
epi =columnar ciliated, no goblet cells, has cilia
lp = ct right under epi, almost negligible
several layers smooth muscle - 4-5 layers
presence of basal bodies at base of axoneme
highly folded mucosa
describe terminal bronchiole
epi = columnar ciliated and non ciliated club cells
lp= so thin almost invisible
2 layers smooth muscle cells
describe respiratory bronchiole
Epithelium =cuboidal club sells (transparent, see mucous)
incomplete smooth muscle
stretches into alveoli
adventitia=thin layer with fibrocytes - also cannot see
looks the same as terminal but wall is interrupted
NO submucosa except SM cells
describe alveolar duct
respiratory bronchiole connected to branching alveolar ducts of decreasing size, alveolar ducts are delimited by knobs of smooth muscle covered by club cells and alveolar sacs around
becomes squamous cells
knobs of mucosa
epithelium= short club cells which produce surfactant
what is middle of alveolar sac
atrium
separated by septi (a septum- could be porous)
describe lung alveoli
alveolar cell type 1 and 2 = pneumocytes types 1 and 2
lots of capillaries in septum - continuous capillaries in lungs - branch from pulmonary artery
interconnected by alveolar poles
which bronchiole is affected by asthma
regular
innervated by sympathetic - relaxation and parasympathetic - produces contraction
a puff of asthma medication opens lumen
describe club cells
transparent
dont stain well
no cilia
secretes surfactant
what is surfactant
avoids collapse of cells
important in tiny structures
need expiration to avoid collapse
why are elastic fibers important in alveoli
very important for structures to expand
inspiration - contract and expiration
describe pneumocyte type 2
Secretes surfactant
bulging cells
not same as club cells
typical of lung alveoli
club = alveolar duct, terminal and respiratory bronchioles
looks pale in LM - since lipid structures
in em = dark due to presence of lamellar bodies
open by exocytosis into lumen and secretes surfactant and will cover surface of alveoli
describe endothelium capillary
lined by simple squamous epithelium on bm
describe pneumocyte type 1
flat cell
simple squamous epi rests on bm
describe macrophages in septi
migrate into septum and become fixed tissue macrophage
free macrophages = move everywhere, eats dust, pollution, asbestos , all particulate matter,
why do tattoos become permanent
due to fixed tissue macrophages
what do lamellar bodies in pneumocytes types 2 do
contain surfactant proteins A,B,C&D and phospholipids
primarily lecithin which helps reduce the surface tension of pneumocytes type 1
describe blood air barrier
gas exchange
structure where exchange of o2/co2 happens
moves from lumen of capillary to lung alveoli
which structures does blood air barrier use
cytoplasm of pneumocyte type 1
BM
cytoplasm of endothelial cell
describe BM of blood air barrier
fused bm of 2 tissues =pneumocyte type 1 and endothelial cell
name equation for how co2 produced in lung
2 H2CO3 + carbonic anhydrase = CO2 + H20
name the 3 means by which co2 is transported in blood stream
from peripheral tissues and back to lungs
dissolved gas
bicarbonate
carbaminohemoglobin bound to hemoglobin and other proteins
describe respiratory distress syndrome of the newborn
life threatening disorder of the lung caused by deficiency of surfactant
associated with prematurity
leading cause of death among premature infants
treatment = recombinant surfactant or cortisone promotes synthesis of surfactant
describe emphysema
chronic lung disease characterized by destruction of inter-alveolar wall (septi) leading to Respiratory insufficiency
major cause = cigarette smoking
probably due to impairment of elastic fiber synthesis
other cases = increased production of elastase by macrophages, leads to some forms of emphysema, results from degradation of elastic fibers of intra alveolar wall
apoptosis
elastase = will destroy elastic fibers and septum will break