unit 2 - ka3: metabolic rate

• Metabolic rate can be measured using respirometers, oxygen probes, carbon dioxide probes and calorimeters.
•  Measurement of oxygen consumption, carbon dioxide and heat production to compare metabolic rates.
• Organisms with high metabolic rates require more efficient delivery of oxygen to cells.
• Birds and mammals have higher metabolic rates than reptiles and amphibians, which in turn have higher metabolic rates than fish.
• Comparative anatomy and physiology of heart chambers and circulatory systems in amphibians, reptiles, mammals and birds, and heart and circulation in fish.
• Birds and mammals have a complete double circulatory system consisting of two atria and two ventricles. Amphibians and most reptiles have an incomplete double circulatory system consisting of two atria and one ventricle. Fish have a single circulatory system consisting of one atrium and one ventricle.
• Complete double circulatory systems enable higher metabolic rates to be maintained. There is no mixing of oxygenated and deoxygenated blood and the oxygenated blood can be pumped out at a higher pressure. This enables more efficient oxygen delivery to cells.