Avian Respiration Flashcards
Describe the flow through the upper respiratory system the lungs and the air sacs
Inhalation
Sternum forward and down, ribs cranially, Lower pressure, air sacs expand
Air moves through the nasal cavity past the larynx (passing through URS). The air flows into the caudal air sacs from the trachea.
Exhalation
Sternum back and up, ribs caudally, decrease volume, forces air out of air sacs
Air is forced into the lungs where has exchange takes place in tubular capillaries rather than alveoli
Inhalation
Air sacs expand drawing up the air from the lungs into the cranial air sacs
Exhalation
Air sacs contract expelling air through the trachea
Describe the structure of the avian lung
Firmly attached to the thoracic wall and remains constant in volume during both phases of respiration.
The primary bronchus enters the lung, giving off at the branching into 4 sets of secondary bronchi before it enters the abdominal air sac
Parabronchi are primarily responsible for continuous gas exchange using a counter current system ato oxygenate and remove waste from the blood
Describe the structure and function of the avian air sac system
Act like reservoirs
Poorly vascularized, no gas exchange
9 (or sometimes 8) air sacs
Connected with pneumatic bones
Evaporative heat loss
Sound production
Describe the role of the skeletal system in avian respiration
Pneumatic bones: Reduce weight
- skull - humerus - clavicle - keel (sternum) - pelvic girdle - vertebrae