Respiratory system Flashcards
divisions of respiratory system
STRUCTURAL:
upper - nasal cavity to larynx
lower - trachea to alveoli
FUNCTIONAL:
conducting zone - nasal cavity to terminal bronchioles
respiratory zone - respiratory bronchiole to alveoli
pleural membranes and fluid
visceral parietal line pleural cavity filled with pleural fluid
pleura attached to the mediastinum
2 functions of pleural fluid:
lubrication, maintenance of pressure to prevent lungs from collapsing during exhalation
general and individual lung shape
conical shape, rounded apex, broader, concave base
LEFT:
smaller, 2 lobes, cardiac notch and lingula
RIGHT:
larger, 3 lobes
lungs surfaces lobes and fissures
diaphragmatic: inferior, concave
costal: anterior lateral posterior
mediastinal: medial, contains indentations from mediastinal organs
superior, inferior and middle lobe, separated by oblique and horizontal fissure
respiratory epithelia structure and function
important for innate immunity
- goblet cells produce mucus
- pseudostratified ciliated columnar epithelial cells sweep mucus up to be coughed
- epithelial cells get flatter and progressively lose cilia
- simple squamous in alveoli and alveolar ducts
nasal cavity conchae and sinuses structure and function
warms and humidifies air
sinuses also help make head lighter, are ciliated, and change pitch of voice
4 pairs of paranasal muscles: frontal, ethmoidal, sphenoidal, maxillary
pharynx 3 sections
nasopharynx (only one ciliated)
oropharynx
laryngopharynx
larynx structure and role of epiglottis
between pharynx and trachea
made up of thyroid cartilage, cricoid cartilage, vocal fold, arytenoid cartilage
epiglottis is a passive cartilaginous structure, prevents food from entering trachea when swallowing
trachea structure (cartilage, between cartilage, posterior surface, carina)
C shaped hyaline cartilage rings ensure trachea is held open
in between cartilage rings: dense regular CT, smooth muscle
posterior wall: soft CT and smooth muscle ensures flexibility when food in esophagus
carina: directs air to right and left bronchi, produces cough reflex
tracheobonchial tree order and structural changes
trachea –> primary bronchi (each lung) –> secondary bronchi (each lobe) –> tertiary bronchi (each bronchopulmonary segment) –> small bronchi –> bronchioles –> terminal bronchioles
increase smooth muscle, decrease cartilage to none at all in terminal, epithelia thins
bronchopulmonary segments structure (blood vessels, alveoli)
tertiary bronchiole and pulmonary arteries branch are located centrally
pulmonary veins located peripherally
alveoli surrounded by capillary beds
terminal bronchioles –> respiratory bronchioles –> alveoli consisting of alveolar ducts and sacs
alveolus and capillary side
ALVEOLUS:
made up of pneumocytes
type 1 - simple squamous, gas exchange
type 2 - simple cuboidal, secrete surfactant to prevent alveoli from collapsing from surface tension
CAPILLARY:
capillary endothelium
both have fused basement membranes
inspiration expiration quiet forced muscle use
QI: diaphragm, external intercostal muscles
FI: diaphragm, accessory muscles (sternocleidomastoid, scalene, pectoralis major)
QE: relaxation of diaphragm and lungs, elastic recoil, no contraction
FE: accessory muscles (internal intercostal muscles, rectus abdominus, external obliques)
inspiration expiration diaphragm position
I: central tendon moves inferiorly, domes flatten out
E: right 5th rib, left 5th intercostal space
2 blood supplies to lungs
pulmonary: arteries superior to veins
bronchial: bronchial arteries –> bronchial veins –> azygous/hemiazygous veins –> superior vena cava/pulmonary vein
