ZOO 2090 Lecture Notes - Lecture 16: Buccal Pumping, Intercostal Muscle, Keratin

• School: University of Guelph
• Department: Zoology
• Course: ZOO 2090
• Professor: Jinzhong Fu

Document Summary

Cutaneous respiration in amphibians: cutaneous respiration is important in amphibians. Can increase surface area in different ways: percent of total gas exchange varies between terrestrial and aquatic amphibians. Tetrapod lungs: mammal top, reptile middle, amphibian bottom, trend toward increased compartmentalization associated with increased body size and metabolic rate. Faveolar lung faveolar lung does not equal unidirectional flow. Tetrapod circulation: for most air breathing tetrapods, blood passes through the heart twice during each circuit. Interatial septum and spiral valve reduced or absent in lungless salamanders. Heart of birds and mammals: 4 chambered hearts with similar design, bt different origins, absence of cardiac shunt probably an adaptation to allow different arterial pressure in lungs vs body in active animals. Response to special need of organs: thermoregulation: keep blood to brain not too hot, not too cold: nasal rete, reduce heat loss from limbs, vascular counter-current exchanger: rete.