Respiration Lecture 15: Histology Flashcards
respiratory tract
tubular system that extends from nares to lungs
Functions of resp. tract
1) warm/moisten air
2) detect odorant molecules
3) conduct air to lungs
4) gas exchange with blood
5) minimize entry of ingested food and fluid
6) produce vocalizations
7) trap/eliminate foreign particles
8) combat microbes
Type of epithelium in vestibular region
nonkeratinized stratified squamous epithelium
2 types of epithelium in respiratory region
respiratory + olfactory ep.
4 main components of nasal cavity
1) vestibular region
2) respiratory region
3) paranasal sinuses
4) vomeronasal organs
philtrum
area between nostril and mouth
respiratory epithelium =
pseudostratified ciliated columnar epithelium
4 main cell types found in resp. ep.
goblet, ciliated, basal, and brush cells
olfactory epithelium =
pseudostratified ciliated columnar epithelium
3 main cell types found in olfactory ep.
sustentacular, olfactory, and basal cells. NO GOBLET CELLS
where are Bowman’s glands found and what do they do?
Beneath olfactory epithelium; secretion dissolves odor-producing substances
Paranasal sinuses fx
provide thermal and mechanical protection to orbits, nasal and cranial cavities; add resonance to vocalizations
T or F: pig has more extensive paranasal sinus than dog
T
What is paranasal sinus lined by?
Resp. ep.
What is vomeronasal organ lined by?
Resp. and Olf. ep., cartilage
vomeronasal organ fx
detect pheromones involved in social and mating behaviors
What is nasopharynx lined by?
resp. ep. (pseudostratified ciliated columbar ep.) Is around the soft palate
What is larynx lined by?
stratified squamous and resp. ep.
Epiglottis is lined by:
Non-keratinized stratified squamous epithelium that interdigitates with the lamina propria
Epithelium in trachea
respiratory ep.
where is trachealis m. in dog vs. ox?
dog-outside smooth muscle ring; ox-inside ring
Tunic layers from inside to outside of tubular organ (4)
1) Tunica mucosa (lines lumen)
2) Tunica submucosa (often contains glands)
3) Tunica muscularis
4) Tunica serosa or adventitia
Main secretory cell type in tracheal epithelum of domestic mammals
goblet cells
lamina muscularis mucosae in trachea contains
elastic fibers
muscularis externa in trachea contains
joining of trachealis m. and cartilage
conducting airways of bronchial tree
trachea + extrapulmonary bronchus
transitional/respiratory bronchioles
char. by direct attachment of alveoli; not present in all species. Between terminal bronchioles and alveolar ducts. Participate in gas exchange
Granular (Type II Pneumonocytes)
Thicker and less numerous than Type I. Secrete surfactant. Aka septal cells
Membranous (Type I) pneumonocytes
squamous cells that line alveolar wall. Thin cells, where gas exchange takes place. Surround capillaries
2 kinds of macrophages in lung tissue
septal (remains w/n connective tissue septa) and alveolar (on alveolar lining, or free in lumen). Scavenge for particulates and move them upward and out via cilia
Passage of air from bronchiole to alveoli
bronchiole –>alveolar duct –>atrium –> alveoli
air-blood barrier components
1) surfactant
2) alveolar membrane
3) interstitial fluid
4) basal laminae of pneumonocyte and enothelium
5) endothelial cell
6) blood plasma
7) red blood cell
what does bronchial artery supply?
resp. structures
What vessels supply gas exchange system?
pulmonary a., alveolar capillaries, pulmonary vein
What innervates resp. system?
Parasympathetic –> vagus (bronchoconstriction)
Sympathetic –> T2-T4 (bronchodilation)
respiratory distress syndrome
lungs collapse and fail to expand
Immotile cilia (Kartagener’s) syndrome
leads to chronic resp. infections
Tracheal hypoplasia
narrowed airway due to abnormal devel. of cartilage rings
T or F: avian hyaline cartilage rings are complete
T
Which components of avian resp. system are lined with resp. epithelium?
Trachea primary bronchi, mesobronchus
Where is lymphatic tissue located in resp. system of birds?
lamina propria of bronchi
avian ventilation circuit
bronchus –> caudal sac –> lung –> cranial sac –> out
Syrinx
where trachea forks into lungs in birds. Where sound is produced via vibrations of typmaniform membrane and pessulus
theory of gastric CO2 prod. and ventilation
during resp. acidosis, excess CO2 travels from gastric artery to stomach and out esophagus
