Respiratory- Dennis Flashcards
Conducting Portion
Collects & warms air • Transmits air to respiratory portion • Nasal cavity, paranasal sinuses, nasopharynx, trachea, • Primary, secondary, & tertiary bronchi • Bronchioles, terminal bronchioles
Respiratory portion:
• Passes air to alveoli with the
purpose of gaseous exchange
• Respiratory bronchioles, alveolar
ducts, alveolar sacs
Respiratory Epithelium
Pseudostratified columnar ciliated
epithelium
• Lamina propria has a rich, vascular
network with a complex set of
capillary loops
• Confined to airways of the
respiratory system
Nasal cavities divided by
nasal septum and has three regions:
Nasal vestibule
Respiratory region
Olfactory region
Nasal vestibule
just inside the
nostrils, lined by skin
Respiratory region
inferior 2/3 of
nasal cavities, lined with respiratory
mucosa
Olfactory region
located at the
apex (upper 1/3), lined by
specialized olfactory mucosa
function of nasal cavities
adjusts temperature &
humidity of inspired air
• Enhanced by large surface area
provided by the turbinate bones
Olfactory Mucosa
- Contains receptors for sense of smell
- Pseudostratified ciliated columnar epithelium (10 cm2 area)
- Olfactory glands → serous secretions that dissolve odorant molecules
Olfactory receptor cells
• Have single dendritic process • Specialized, nonmotile cilia w/ odorant receptors • Ligand binding causes signals to be sent to olfactory bulb
Basal cells
stem cells for olfactory receptor & supporting cells
Brush cells
Ciliated, columnar epithelial cells
Supporting/sustentacular cells
provide mechanical & metabolic support to
olfactory receptor cells
Trachea
• Short, flexible, air tube that serves as
a conduit for air
• Extends from the larynx & divides into
the main/primary bronchi
• Lumen of the trachea remains open
because of stacked cartilaginous rings
Four layers
Mucosa
composed of a ciliated,
pseudostratified epithelium and an
elastic, fiber
-rich lamina propria