A&P 22: The Respiratory System Flashcards
Respiratory System
system that supplies the body with oxygen and disposes of carbon dioxide
Respiration
pulmonary ventilation, external respiration, transport of respiratory gases, and internal respiration are collectively known as this function
Pulmonary ventilation
breathing; air moving in and out of the lungs (during inspiration and expiration) so the gases there are continuously changed and refreshed
External respiration
oxygen diffuses from the lungs to the blood, and carbon dioxide diffuses from the blood to the lungs
Transport of respiratory gases
oxygen is transported from the lungs to the tissue cells of the body, and carbon dioxide is transported from the tissue cells to the lungs; the cardiovascular system accomplishes this transport using blood as the transporting fluid
Internal respiration
oxygen diffuses from blood to tissue cells, and carbon dioxide diffuses from tissue cells to blood
Respiratory zone
actual site of gas exchange; composed of the respiratory bronchioles, alveolar ducts, and alveoli, all microscopic structures
Conducting zone
includes all other respiratory passageways, which provide fairly rigid conduits for air to reach the gas exchange sites
Nostrils (nares)
external openings of the nose
Nasal cavity
internal cavity lying in and posterior to the external nose
Nasal septum
the nasal cavity is divided by this midline, formed anteriorly by the septal cartilage and posteriorly by the vomer bone and perpendicular plate of the ethmoid bone
Posterior nasal apertures
the nasal cavity is continuous posteriorly with the nasal portion of the pharynx through these “funnels” called choanae
Hard palate
where the palate is supported by the palatine bones and processes of the maxillary bones
Soft palate
the unsupported posterior portion is this muscular palate
Nasal vestibule
part of the nasal cavity just superior to the nostrils; lined with skin containing sebaceous and sweat glands and numerous hair follicles
Vibrissae
nose hairs; filter coarse particles from inspired air
Olfactory mucosa
small patch of this lines the slitlike superior region of the nasal cavity and contains smell receptors in its olfactory epithelium
Olfactory epithelium
where smell receptors are contained
Respiratory mucosa
lines most of the nasal cavity; pseudostratified ciliated columnar epithelium, containing scattered goblet cells, that rests on a lamina propia richly supplied with seromucous nasal glands
Paranasal sinuses
the nasal cavity is surrounded by a ring of these chambers; located in the frontal, sphenoid, ethmoid, and maxillary bones
Sinusitis
inflamed sinuses
Pharynx
funnel-shaped organ that connects the nasal cavity and the mouth superiorly to the larynx and esophagus inferiorly
Nasopharynx
posterior to the nasal cavity, inferior to the sphenoid bone, superior to the level of the soft palate; part of the pharynx serving only as an air passageway
Pharyngeal tonsil
AKA adenoids; traps and destroys pathogens entering the nasopharynx in air
Oropharynx
part of the pharynx lying posterior to the oral cavity & continuous with it through an archway (isthmus of fauces)
Isthmus of fauces
archway continuous with the oropharynx
Palatine tonsils
paired tonsils embedded in the lateral walls of the oropharyngeal mucosa just posterior to the oral cavity
Lingual tonsil
tonsil covering the posterior surface of the tongue
Laryngopharynx
serves as a passageway for food and air; lined with a stratified squamous epithelium; directly posterior to the upright epiglottis and extends to the larynx, where the respiratory and digestive pathways diverge
Larynx
voice box; extends for 5cm from the level of the 3rd to the 6th cervical vertebra
Thyroid cartilage
large, shield-shaped cartilage formed by the fusion of 2 cartilage plates
Laryngeal prominence
midline; marks the fusion point of 2 cartilage plates; obvious externally as the Adam’s Apple
Cricoid cartilage
ring-shaped cartilage perched atop and anchored to the trachea inferiorly
Arytenoid, cuneiform, & corniculate cartilages
3 pairs of small cartilages that form part of the lateral and posterior walls of the larynx
Epiglottis
9th cartilage; flexible, spoon-shaped structure; composed of elastic cartilage and is almost entirely covered by a taste bud-containing mucosa
Vocal ligaments
ligaments that attach they arytenoid cartilages to the thyroid cartilage; composed largely of elastic fibers; form the core of mucosal folds (vocal cords)
Vocal folds (true vocal cords)
mucosal folds, appear pearly white because they lack blood vessels; vibrate, producing sounds as air rushes up from the lungs
Glottis
the vocal folds and the medial openings between them through which air passes
Vestibular folds (false vocal cords)
superior to the vocal folds is a similar pair of mucosal folds; play no direct part in sound production but help to close the glottis when we swallow
Laryngitis
inflammation of the vocal folds
Valsalva’s Maneuver
the vocal folds acting as a sphincter that prevents air passage; during abdominal straining associated with defecation, the glottis closes to prevent exhalation and the abdominal muscles contract, causing the intra-abdominal pressure to rise; these events help empty the rectum and can also splint/stabilize the body trunk when lifting a heavy load
Trachea
windpipe; descends from the larynx through the neck and into the mediastinum; ends by dividing into the 2 main bronchi at midthorax
Submucosa
connective tissue layer deep to the mucosa containing seromucous glands that help produce the mucus sheets within the trachea
Adventitia
outermost layer of connective tissue of the trachea
Trachealis
the open posterior parts of the cartilage rings of the trachea, which abut the esophagus; connected by smooth muscle fibers of this & by soft connective tissue
Carina
spar of cartilage as the last tracheal cartilage is expanded; projects posteriorly from the inner face of the trachea; marks the point where the trachea branches into 2 main bronchi
Heimlich maneuver
procedure in which air in the victim’s lungs is used to expel an obstructing piece of food
Bronchial tree
the air passageways in the lungs branch again and again (about 23 times overall) in a pattern called this
Right and left (primary) bronchi
the trachea divides to form these passageways; approximately at the level of T7 in an erect/standing person
Lobar (secondary) bronchi
once inside the lungs, each main bronchus subdivides into these passageways, 3 on the right and 2 on the left, each supplying one lung lobe
Segmental (tertiary) bronchi
the lobar bronchi branch into 3rd order segments, which divide repeatedly into smaller and smaller bronchi
Bronchioles
passages smaller than 1mm in diameter
Terminal bronchioles
smallest of the passages in the lungs; less than 0.5mm in diameter
Alveoli
thin-walled air sacs
Respiratory bronchioles
the respiratory zone begins as the terminal bronchioles feed into these passages within the lungs
Alveolar ducts
the respiratory bronchioles lead into these winding ducts, whose walls consist of diffusely arranged rings of smooth muscle cells, connective tissue fibers, and outpocketing alveoli
Alveolar sacs/saccules
the alveolar ducts lead into these terminal clusters of alveoli
Type I alveolar cells
the walls of the alveoli are composed primarily of as single layer of these squamous epithelial cells, surrounded by a flimsy basement membrane
Respiratory membrane
the capillary and alveolar walls and their fused basement membranes form this 0.5 micrometer thick blood air barrier that has blood flowing past on 1 side and gas on the other
Type II alveolar cells
cells that secrete a fluid containing a detergent-like substance called surfactant that coats the gas-exposed alveolar surfaces
Alveolar pores
openings connecting adjacent alveoli that allow air pressure throughout the lung to be equalized and provide alternate air routes to any alveoli whose bronchi have collapsed due to disease
Alveolar macrophages
phagocytes that crawl freely along the internal alveolar surfaces
Lungs
pair of structures that occupy all of the thoracic cavity except the mediastinum, which houses the heart, great blood vessels, bronchi, esophagus, and other organs
Root
each cone-shaped lung is surrounded by pleurae and connected to the mediastinum by vascular & bronchial attachments, collectively called this
Costal surface
the anterior, lateral, and posterior lung surfaces lie in close contact with the ribs and form this continuously curving surface
Apex
narrow superior tip of the lung, just deep to the clavicle
Base
concave, inferior surface of the lung that rests on the diaphragm