Topic 14: Respiratory System Flashcards
What are the main functions of the respiratory system
-air movement (ventilation) (in+out of lungs)
-exchange of gases between the lungs and blood (O2 + CO2)
What are the 2 subdivisions of the respiratory system?
-upper respiratory system
-lower respiratory system
what does the upper respiratory system contain?
-nose
-nasal cavity
-pharynx
what does the lower respiratory system contain?
-larynx
-trachea
-bronchial tree
-lungs
What is the mucosa lining of the respiratory system?
-ciliated pseudostratified epithelial tissue with goblet cells
-lamina propria (areolar CT)
what is the purpose of the epithelial tissue being ciliated?
-cilia sweeps mucus to the esophagus where it gets swallowed
what is the structure of the nose?
-supported by bone and hyaline cartilage
-contains nostrils/nares
what is the main entry point of the respiratory system? what can also be considered an entry point? why is this not the main entry point?
-nostrils are the main entry point
-the mouth is another entry point
-not the main entry point because it is the main entry point of the digestive system
what is the only visible part of the respiratory system?
-nose
what are the functions of the nasal cavity?
-airway passage (heats, moistens, and filters air)
-olfaction (smell)
-speech (resonance chamber)
what is a resonance chamber?
-transfers sound energy to the air
what divides the nasal cavity? what creates this?
-nasal septum
-anterior portion is hyaline cartilage
-posterior portion is made up of bone (vomer=main) (ethmoid=main) (maxillae=small) (palatine bones=small)
what are the 3 areas of the nasal cavity?
-vestibule
-respiratory area
-olfactory area
what is the vestibule area of the nasal cavity?
-anterior region
-no mucosa
-lined by thin skin with hair to filter dust + pollen
what is the respiratory area of the nasal cavity?
-posterior region
-contains chonchae + nasal meatuses
-opening for the nasolacrimal duct
what are chonchae?
-protrude medially from the lateral walls of the respiratory area of the nasal cavity
-superior + middle (projection of the ethmoid)
-inferior (separate bone)
what do the chonchae and nasal meatuses cause?
-air turbulence to humidify air and trap dust and pollen onto the ciliated epithelium
what does the nasolacrimal duct connect? what does this allow for?
-the medial region of the eye to the inferior nasal meatus
-lacrimal fluid (tears) to drain into the nasal cavity
what is the olfactory area of the nasal cavity?
-roof of the nasal cavity
-mucosa contains olfactory neurons (sensory receptors for sense of smell)
what are the paranasal sinuses?
-8 air filled spaces in the skull (no blood flow)
-paired left and right
-open directly into the nasal cavity
where are the paranasal sinuses located?
-frontal
-sphenoid
-ethmoid
-maxillae
what is the function of the paranasal sinuses?
-to warm and moisten air
what is sinusitis?
-inflammation of the mucous membranes within the sinuses due to infection
what is the pharynx also known as?
-throat
what are the 3 regions of the pharynx?
-nasopharynx
-oropharynx
-laryngopharynx
what are the characteristics of the nasopharynx?
-posterior to the nasal cavity
-passage for air only
-contains pharyngeal tonsil + openings
what are the openings of the nasopharynx?
-2 posterior nasal apertures
-2 pharyngotympanic (auditory) tubes
what are the characteristics of the oropharynx?
-posterior to the oral cavity
-air + food passage
-mucosa is stratified squamous epithelium
-extends from the soft palate to the top of the epiglottis
-contains the other palatine tonsils and lingual tonsil
what are the characteristics of the laryngopharynx?
-posterior to the larynx
-air + food passage
-mucosa is stratified squamous epithelium
-extends from the epiglottis to the opening of the larynx
what are the characteristics of the larynx?
-anterior to the laryngopharynx
-air passage only
-made of 8 hyaline cartilages and 1 elastic cartilage
what are the characteristics of the epiglottis?
-covers the glottis during swallowing to prevent food from entering the larynx
-made of elastic cartilage (flexible)
what forms the vocal cords?
-2 paired folds under the laryngeal mucosa in the mid larynx
-ligaments
what are the two paired vocal cord folds?
-vestibular folds
-vocal folds
what is the vestibular fold?
-false vocal cords
-superior fold
-helps close the glottis
what is the vocal fold?
-true vocal cords
-inferior fold
-produce sound by vibration
what is the glottis?
-the space that includes the true vocal cords and their opening between
-closes to prevent food + liquid from entering the trachea
what is laryngitis? what causes it?
-inflammation of the larynx
-can arise from infection or irritation
what is the trachea?
-connects the larynx to the main bronchi
-20 C-shaped pieces of hyaline cartilage
-air passageway only
what is the trachea’s anatomical position in relation to the esophagus?
-trachea is anterior to the esophagus
why does the opening of the C-shaped cartilage of the trachea face the esophagus?
-to allow for expansion of the esophagus (contractions)
what is the bronchial tree?
-connects the trachea to the alveoli of lungs
-extends from left and right main bronchi to alveolar ducts
-air passageway that branches into very small passageways
what are the two types of structures within the bronchial tree?
-conducting zone structures
-respiratory zone structures
what are the conducting zone structures?
-2 main (primary) bronchi (left/right)
-5 lobar (secondary) bronchi (3 right/2 left)
-segmental bronchi (various branching)
-terminal bronchioles (various branching)
what is the transition of mucosa from the main bronchi to the terminal bronchioles?
-ciliated pseudostratified epithelium to ciliated simple cuboidal epithelium
what are the respiratory zone structures?
-respiratory bronchioles (various branching)
-alveolar ducts (tips of bronchial tree)
-alveoli
-sites of gas exchange
what are alveoli?
-honeycomb-like chambers
-main site of gas exchange
-form part of the respiratory membrane
-have millions
what is the transition of mucosa from the respiratory bronchioles to the alveolar ducts?
-ciliated simple cuboidal epithelium to simple squamous
what is purpose of surfactant?
-covers the inner surface of alveoli
-reduces attractive forces between water molecules
-makes it easier for alveoli to expand during inhalation
why does the blood going through the pulmonary veins coming from the lung/bronchial tissue stay oxygenated?
-most blood is already oxygenated
-has little effect
what separates the right and left lung?
-mediastinum (cavity)
how many lobes does each lung have?
-right = 3 lobes, superior, middle, inferior
-left = 2 lobes, superior, inferior
what does the left lung contain that the right lung does not?
-cardiac notch (spot where the heart lies)
what is the serous membrane of the lungs called?
-pleura
-visceral and parietal pleura
-forms the pleural cavity
where is the visceral layer of the pleura located?
-on the surface of the lung
where is the parietal layer of the pleura located?
-on the inner thoracic wall, superior diaphragm and mediastinum
what is the purpose of the pleural cavity?
-filled with serous fluid
-prevents friction when the lungs move
-holds lungs to the thoracic cavity wall
what makes up the respiratory membrane?
-3 layers
-2 epithelia + their fused basement membrane
what are the 3 layers of the respiratory membrane?
-wall of alveolus (alveoli)
-basement membranes of the alveolus + capillary
-wall of capillary
what forms the walls of the alveoli?
-simple epithelium
-2 cell types
what are the 3 cell types in the alveolus wall?
-Type I alveolar cells
-Type II alveolar cells
what are the characteristics of type I alveolar cells?
-simple squamous
-allow for gas diffusion
-majority of the cells
what are the characteristics of type II alveolar cells?
-simple cuboidal
-secrete surfactant
what are the characteristics of macrophages?
-free moving between blood and alveoli
-remove dust, pathogens and cellular debris
-white blood cells
what allows for air movement between adjacent alveoli?
-alveolar pores (openings)
what type of tissue is the wall of a capillary?
-simple squamous epithelium
-endothelium
what are the characteristics of bronchial circulation?
-subdivision of systemic
-blood used to nourish the lung tissue
-contains bronchial arteries (arise from aorta)
-bronchial vein OR pulmonary veins
what do the bronchial arteries carry? where to? where not to?
-oxygenated blood
-to lung tissues (ex: bronchi)
-not to the respiratory portions
where does the returning blood of bronchial circulation come from?
-bronchial veins (little blood) to right atrium
-pulmonary veins (most blood) to left atrium
what is pulmonary edema?
-accumulation of fluid in the lungs
-between cells + within alveoli
what is pulmonary embolism?
-blockage of pulmonary vasculature (blood vessels)
-due to blood clot, arteriosclerosis, air bubbles in vessels
what are nasal meatuses?
-channels between nasal chonchae where air passes
what is the purpose of there being no blood flow in the paranasal sinuses?
-make the skull lighter
what do the two posterior nasal apertures connect?
-nasal cavity to the nasopharynx
what do the two pharyngotympanic (auditory) tubes connect?
-middle ear to the nasopharynx
where is the pharyngeal tonsil located?
-on the posterior wall
what is the one elastic cartilage in the larynx?
-epiglottis
where do the 2 main bronchi branch off and where do they lead?
-branch off the trachea and lead to each lung
