circulation and respiration Flashcards
Q 10 effects
enzymatic activity of the body increases 10x for every 2-3 degree increase in temperature; metabolically expensive; increased reaction time, muscle speed power and endurance, and habitat use
air movement in birds
nares > nasal cavity > trachea > paired bronchi > posterior air sacs > para bronchi of the lungs > anterior air sacs > bronchi > trachea > outside
respiratory adaptations
dense system: more oxygen in less space
compact lungs to reduce weight with unidirectional airflow
typically 9 air sacs and valves
no diaphragm
water maintaining mechanisms
2 breath cycle
1st inhalation: air moves to posterior air sacs
1st exhalation: air moves over lung
2nd inhalation: air moves to anterior air sacs
2nd exhalation: air moves out
intraclavicular air sac
9th unpaired air sac included in the anterior air sacs, involved in singing and displays
efficiency of avian respiration
decreased amount of used air in the lungs
increased oxygen extraction
reduced negative effects of hyperventilation
cross current blood flow
blood flows perpendicular to the lungs and passes over multiple times to collect as much oxygen as possible
air sacs
between 6 and 12, typically 9 in 4 pairs and 1 unpaired
fercula
plays an important role in respiration with compression from flapping causing respiration rates to sync with wing beats
avian heart
41% larger than in similar sized mammals; high cardiac output due to increased stroke volume; ventricles fill and empty more completely
heart rate
larger metabolic scope (HR range) than in mammals, high in activity but low resting heart rates due to increased stroke volume; extremely high blood pressure
heart muscle fibers
more fibers than in similar mammals, thinner muscle fibers rich in mitochondria to increase oxygen acquisition and aerobic capacity
