BIOD33H3 Lecture Notes - Lecture 3: Myofibril, Leucine, Basal Metabolic Rate
Document Summary
Bar-headed geese can fly at faster speeds, at not an increased metabolic cost. Bigger maintenance cost to pay (have to maintain more feathers, etc. ) Due to the increased capacity to ventilate lungs. When total ventilation increases, co2 is purged from the blood (easier for it to diffuse out: bring in huge amounts of fresh air into the lungs, making it easier for co2 to leave to body. Co2 levels drop: as oxygen levels drop, this stimulates an increase in ventilation, this decreases blood levels of co2, and chemoreceptors then try to suppress ventilation. Co2 acts as an acid in the blood (alters ph) Bar-headed geese may have more or less sensitive chemoreceptors. Poikilocapnic - capnic refers to carbon dioxide, poikilo refers to varaiable: did not control blood co2 levels. Isocapnic - iso refers to same: held blood co2 levels constant. When others birds increase total ventilation, they do it largely by increasing breathing frequency (10bpm to 30bmp)
