Topic 14 -Respiratory system Flashcards
2 subdivisions
Upper respiratory system -nose, nasal cavity, pharynx
lower respiratory system -larynx, trachea, bronchial tree, lungs
the upper and lower subdivisions are lined with
mucosa (with one exception) -vestibule in nasal cavity lined with coarse hairs
all have epithelial tissues + CT
epithelial tissue for most= ciliated pseudostratified columnar epithelium (with goblet cells)
cilia sweep mucus to esophagus where swallowed
connective tissue layer of ALL mucosa =lamina propria
Nose
what is it supported by
nostrils=
supported by bone and hyaline cartilage
nostrils=nares
Nasal Cavity functions
airway passage (warm and moisten air)
olfaction
speech (resonance chamber)
what is the nasal cavity divided by
what is the anterior part made up of?
posterior part?
nasal septum
anterior part=hyaline cartilage
posterior part=vomer, ethmoid, maxillae and palatine bones
what are the 3 areas of the nasal cavity
vestibule
respiratory area
olfactory area
vestibule
anterior region of nasal cavity
lined by skin with coarse hairs
respiratory area of nasal cavity
posterior region
mucosa=ciliated pseudostratified epithelium + CT
conchae protrude from walls
-superior and middle both part of ethmoid
inferior -separate bone
inferior to each concha= a nasal meatus (shallow groove)
-conchae and meatuses cause air turbulence to knock out dust
-lacrimal duct opens into cavity (just below inferior nasal concha)
-tears into nasal cavity
olfactory area
sense of smell
roof of cavity
neurons=olfactory receptors
Paranasal sinuses
8 air-filled spaces in skull, paired left and right spaces in: frontal, sphenoid, ethmoid, maxillae
opens directly into nasal cavity
function: warm and moisten air, lighten skull
what is sinusitis
inflammation of mucous membrane
Pharynx (throat)
3 regions
skeletal muscle lined by mucous membrane
nasopharynx
oropharynx
laryngopharynx
nasopharynx
-posterior to nasal cavity
-air passage only
-contains pharyngeal tonsil
-openings: 2 posterior nasal apertures (interior nares)
2 pharyngotympanic (auditory) tubes
oropharynx
posterior to oral cavity passage for air and food stratified squamous epithelium (abrasion) -from soft palate to epiglottis contains palatine and lingual tonsil
laryngopharynx
air and food passage
stratified squamous epithelium
from epiglottis to lower opening of larynx
Larynx
air passage only
made of 9 cartilages, all hyaline cartilage
vocal cords
glottis
9 cartilages of the larynx
3 unpaired cartilages
thyroid cartilage -on anterior wall, Adams apple
cricoid cartilage -forms complete ring
epiglottis -covers glottis during swallowing, elastic cartilage
paired cartilage: arytenoid -attaches vocal cords don’t need to know other two
vocal cords (part of larynx)
2 paired folds in the mucosa
vestibular fold -false vocal cords, superior fold
vocal fold =true vocal cords
inferior fold, produce sound by vibration
glottis (part of larynx)
true vocal cords plus opening
-closes to prevent food + liquid entering trachea
laryngitis
inflammation of larynx
can arise from infection, irritation
trachea
connects larynx to main bronchi
anterior to esophagus
cocnsists of 20 C-shaped pieces of hyaline cartilage
open part of C faces esophagus -permits expansion of esophagus
Bronchial Tree
main bronchi to alveolar ducts
decreasing hyaline cartilage and increasing smooth muscle
2x main (1°) bronchi -1 to each long
5x lobar (2°) bronchi -1 to each lunch lobe
many segmental (3°) bronchi, 4th order etc.
smooth muscle and elastic fibres (no cartilage)
many terminal bronchioles
many respiratory bronchioles
many alveolar ducts
gradual change of epithelium mucosa in bronchial tree
Main bronchi have
Terminal bronchioles have
Alveolar ducts have
Main (1°) Bronchi -ciliated pseudostratified columnar epithelium
terminal bronchioles -non-ciliated simple columnar
alveolar ducts -non-ciliated simple squamous
Lungs
how many lobes for right and left lung
what is the pleura? pleura cavity?
right and left=separated by mediastinum
right lung=3 lobes superior, middle, inferior
left lung =2 lobes, superior and inferior, has cardiac notch where heart lies
pleura=serous membrane
-visceral on surface of lung
-parietal on inner thoracic wall, superior diaphragm and mediastinum
pleural cavity= filled with serous fluid, prevents friction when lungs move, holds lungs to thoracic cavity wall
what is the conducting zone (conduct air)
nasal cavity to terminal bronchioles
what is the respiratory zone (gas exchange with air)
respiratory bronchioles to alveolar ducts to alveoli
most gas exchange occurs by the alveoli, O2 into blood, CO2 into air
respiratory membrane
what are the 3 layers?
consists of alveolar walls + surrounding capillaries
- 2 epithelia and their fused basement membranes
wall of alveolus
basement membrane of alveolus +capillary
wall of capillary -simple squamous epithelium (endothelial cell)
wall of alveolus 3 cell types
simple epithelium
1) type 1 alveolar cells -simple squamous, gas diffusion
2) type 2 alveolar cells -simple cuboidal, secrete surfactant -allows lungs to expand with ease
3) macrophages -free moving across surface of type 1 cells -remove dust and debris
what do alveolar pores do
allow for movement of air between alveoli
blood supply to lung 2 routes
pulmonary circulation=blood to be oxygenated
bronchial circulation= subdivision of systemic, blood nourish lung tissue
pulmonary circulation
deoxy (right ventricle -> pulmonary trunk -> pulmonary arteries) -> capillaries in respiratory portion of lungs -> oxy (pulmonary veins -> left atrium)
Bronchial circulation description
Bronchial arteries: arise from aorta (systemic), carry oxygenated blood to tissues except respiratory zone
returning to heart blood drains into: bronchial vein (little blood) to right atrium -systemic
OR pulmonary veins (most blood) to left atrium -pulmonary
bronchial circulation route
oxy (left ventricle ->aorta -> bronchial arteries )-> all lung bronchial tissue (except respiratory zone) -> deoxy (bronchial vein -> vena cava -> right atrium OR pulmonary vein )-> oxy (left atrium)
Pulmonary Edema
accumulation of fluid in the lungs -between cells and alveoli
Tuberculosis (Mycobacterium tuberculosis) (TB)
thickens respiratory membrane -lung tissue replaced by fibrous CT (scars)
decreased lung elasticity and gas exchange area
Pulmonary embolism
blockage of pulmonary vasculature
-due to blood clot, arteriosclerosis, air bubbles in vessels
Pneumothorax
entry of air in pleural cavity
causes lung to collapse
two types -can breath in or out OR breathing out closes hole
Emphysema
alveolar walls breakdown fewer, larger alveoli decreased surface area for gas exchange decreased elasticity (hard to breathe) + recoil (less air out out on exhalation)
ventilation (breathing)
muscles are all skeletal
inspiration: intake air
diaphragm + external intercostals contract
expiration: air exits
diaphragm + external intercostal relax
exhaling=passive process
