respiratory system Flashcards
main funtions
- air movement- in and out of lungs
- exchange of gases (O2 and CO2) b/w lungs and blood
2 sub divisions
upper and lower respiratory system
upper repsiratory system
nose, nasal cavity, pharynx
lower respiratory system
larynx, trachea, bronchial tree, lungs
lined with ?
mucosa (with one exception)
all have what type of tissue?
epithelial and CT
(epithelial tissue for most=ciliated pseudo-stratified columnar epithelium with goblet cells)
(connective tissue layer of all mucosae= lamina propria)
what does cilia do?
sweep mucus to esophagus where swallowed
respiratory system structures
nose nasal cavity paranasal sinuses pharynx (throat) larynx (voice box) trachea bronchial tree lungs respiratory membrane
nose
supported by bone and hyaline cartilage
nostrils=nares
nasal cavity funtions
- airway passage (warm and moisten air)
- olfaction
- speech (resonance chamber)
nasal cavity divided by
nasal septum (anterior part=hyaline cart posterior part=vomer, ethmoid, maxillae, palatine bones)
nasal cavity three areas
- vestibule
- respiratory area
- olfactory area
vestibule
anterior region
lined by skin with coarse hairs
respiratory area
posterior region
-mucosa=ciliated pseudostratifed epithelium and CT
-conchae protrude from walls : superior, middle (both part of ethmoid), inferior (separate bone)
-inferior to each conchae = 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
- open directly into nasal cavity
paranasal sinuses function
warm, moisten air
lighten skull
paranasal sinusitis
inflammation of mucous membrane
pharynx (throat)
-skeletal muscle lined by mucous membrane
pharynx has three regions
nasopharynx
oropharynx
laryngopharynx
nasopharynx
- posterior to nasal cavity
- air passage only
nasopharynx contains
- pharyngeal tonsil
opening: - 2 posterior nasal apertures
- 2 pharyngotympanic (eustachian tubes)
oropharynx
posterior to oral cavity
- air and food passage
- stratified squamous epithelium (abraision)
- from soft palate to epiglottis
oropharynx contains:
palatine tonsils
lingual tonsils
laryngopharynx
air and food passage
- stratified squamous epithelium
- from epiglottis to opening of larynx
larynx (voice box)
air passage only
made of 9 cartilages
-all hyaline cartilages (except epiglottis)
3 unpaired cartilages and 3 paired cartilage
-vocal chords = 2 paired folds in the mucosa
-contains glottis and laryngitis
unpaired cartilage in larynx
- thyroid cartilage (on anterioir wall=adams apple)
- cricoid cartilage (forms complete ring)
- epiglottis (covers glottis during swallowing, elastic cartilage)
paired cartilage
- arytenoid - attached vocal chords
- dont need to know other two
vocal chords = 2 paired folds in the mucosa
- vestibular fold
- false vocal chords
- superior fold - vocal fold
- true vocal chords
- produce sound by vibration
glottis
true vocal chords plus opening
closes to prevent food and liquid from entering trachea
laryngitis
inflammation of larynx
-can arise from infection, irritation
trachea
-connects larynx to main bronci
-anterior to esophagus
-consists of 20 c-shaped pieces of hyaline cartilage
(open part of C faces esophagus- permits expansion of esophagus)
bronchial tree
refer to page 4
-main bronci=alveolar ducts
epithelium of mucosa shows gradual change
lungs 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)
lungs parts
right and left lung
pleura
pleural cavity
respiratory zone
pleura
serous membrane
- visceral-on surface of lung
- parietal-on inner thoracic wall, superior diaphragm and mediastinum
pleural cavity
filled with serious fluid
-prevents friction when lungs move
-holds lungs to thoracic cavity wall
refer to page 6
respiratory zone in lungs
respiratory bronchioles, alveolar ducts, alveoli
-O2 enters blood, Co2 enters air (gas exchange occurs mainly ini alveoli
respiratory membrane
consists of alveolar walls and surrounding capillaries
-3 layers = 2 epithelia and their fused basement membranes
respiratory membrane layers
wall of alveolus
basement membrane of alveolus and capillary
wall of capillary
wall of alveolus
simple epithelium -made of 3 cell types: type 1 alveolar cells types 2 alveolar cels marcrophages note: alveolar pores allow air movement b/w aleoli
type 1 alveolar cells
simple squamous
allow gas diffusion
type 2 alveolar cells
simple cuboidal
secrete surfactant
(allows lungs to expand with ease)
macrophages
free-moving across surface of type 1 cells
remove dust and debris
wall of capillary
simple squamous epithelium= endothelial cell
blood supply to lung has two routes
pulmonary circulation
-blood to be oxygenated
bronchial circulation
-blood to nourish lung tissue
pulmonary circualtion
- right vent->pulm trunk->pulm arteries->capillaries in respiratory portion of lungs (deoxy)
- > pulmonary veins->left atrium (oxy)
bronchial circulation bronchial arteries
arise from aorta (systemic)
-carry oxygenated blood to tissues (eg. bronchi) except respiratory zone
bronchial circulation returning to heart, blood drains into:
- bronchial vein (little blood) to right atrium- systemic)
- or pulmonary veins (most blood) (to left atrium- pulmonary)
- refer to page 8
clinical applications (5)
- pulmonary edema
- tuberculosis
- pulmonary embolism
- pneumothorax
- emphysema
pulmonary edema
accumulation of fluid in the lungs - b/w cells and within alveioli
tuberculosis
mycobacterium tuberculosis (TB)
- thickens respiratory membrane- lung tissue replaces 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, etc.
pneumothorax:
entry of air into pleural cavity
causes lung to collapse
emphysema
alveolar walls break down
- fewer, larger alveoli
- decreased surface of area for gas exchange
- decreased elasticity (hard to breathe) and recoil (less air out on exhalation)
ventilation (breathing)
muscles are all skeletal
-inspiration and expiration
inspiration
intake of air
-diaphragm and external intercostals contract
expiration
- air move to atmosphere from lungs
- diaphragm and external intercostals relax
- exhaling = passive process
