Respiratory System Flashcards
(165 cards)
Upper respiratory tract
Sphenoidal sinus, frontal sinus, nasal cavity, and pharynx
Lower respiratory tract
Larynx, trachea, bronchi, and lungs
Respiration
Exchange of O2 and CO2 to and from the blood
Only occurs at the lowest portion of the respiratory tract
Conducting portion
Cleans and humidifies air and provides a conduit for
air movement to and from the alveoli. A combination of cartilage, collagen and elastic fibers, and smooth muscle provides structural support and the necessary flexibility and extensibility. Mostly pseudostratified ciliated columnar epithelium.
Nasal cavities
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Terminal bronchioles
Respiratory portion
Provides the sites for the exchange of O2 and CO2
between air and blood.
Respiratory bronchioles
Alveolar ducts
Alveoli are small, air-filled, saclike structures that make up most of the lung
structure.
Nasal cavities
The two nasal cavities (separated by the nasal septum) have pseudostratified columnar epithelium (= respiratory epithelium).
The conchae, or turbinate bones, are three bony shelflike projections extending from each lateral wall of the nasal cavity.
Mucosa (or mucous membrane)
One or more layers of epithelial cells that secrete
mucus, and an underlying layer of loose connective tissue (lamina propria).
Mucosa covering the conchae functions
Releases heat to warm that air.
The air is humidified
Remove particulate and gaseous air impurities.
Contain immunoglobulin A (IgA) from plasma cells.
Respiratory epithelium
The classic example of
pseudostratified ciliated
columnar epithelium.
Two most important cell types:
Ciliated columnar cells
Mucus-secreting goblet cells
Olfactory Epithelium
The olfactory mucosa covers the superior conchae bilaterally and sends axons from throughout its entire 10 cm2 area to the brain via small openings in the cribriform plate of the ethmoid bone. The olfactory cells are bipolar
olfactory neurons; Their dendrites are at the luminal end and have cilia specialized with many membrane receptors for odor molecules.
Anosmia
The loss or reduction of the ability to smell caused by traumatic damage to the ethmoid bone (e.g., severe broken nose) that severs olfactory nerve axons
Hyposmia
The loss or reduction of the ability to smell caused by damage to the olfactory epithelium caused by intranasal drug use.
Pheromones
Secreted substances that alter social behavior;
e.g., alarm pheromones, food trail pheromones, sex
pheromones.
Vomeronasal organ
A second “smell” organ, in the nasal passageway of many animals.
It is a pheromone receptor in most other primates and other mammals. However, in humans and chimps the organ does not appear to
be functional
Paranasal Sinuses
Bilateral cavities in the frontal, maxillary, ethmoid,
and sphenoid bones.
They are lined with a thinner respiratory epithelium having fewer goblet cells producing mucus.
Pharynx from nose to throat
Nasopharynx, oropharynx, and laryngopharynx
Larynx
The larynx is a short (4 cm × 4 cm) passage for air between the pharynx and the trachea. Its rigid wall
is reinforced by hyaline cartilage (in the thyroid, cricoid, and the inferior arytenoid cartilages) and
smaller elastic cartilages (in the epiglottis, cuneiform, corniculate, and the superior arytenoid cartilages), all of which are connected by ligaments. In addition to maintaining an open airway, movements of these cartilages by skeletal muscles participate in sound production during
phonation.
Epiglottis
A flattened structure projecting from the upper rim of the larynx, prevents swallowed food or fluid from entering that passage.
Vocal cords
Vocal ligament (fold) + conus elasticus + vocalis muscle + thyroarytenoid muscle
Laryngitis
Typically due to viral
infection and is usually accompanied by edema of the lamina propria. This changes the shape of the vocal folds or other parts
of the larynx, producing hoarseness or complete loss of voice.
Trachea
Lined with respiratory
mucosa which contains
seromucous glands producing watery mucus.
A series with about a dozen C-shaped rings of hyaline cartilage reinforces the wall and keeps the tracheal lumen open.
Bronchial Tree
The trachea divides into two primary bronchi that
enter each lung at the hilum
After entering the lungs,
the primary bronchi give rise to three secondary
(lobar) bronchi in the right lung and two in the left lung, each of which supplies a pulmonary lobe.
These lobar bronchi again divide, forming tertiary
(segmental) bronchi.
The tertiary bronchi give rise to smaller bronchi, whose branches are called bronchioles. These are
important in bronchoconstriction and bronchodilation.
Each bronchiole branches to form five to seven
Bronchioles
The smallest branches of the bronchial
They lack both mucosal glands and cartilage.
Bronchi epithelium
Respiratory