What are the metabolic waste products produced when animal cells use each of the macromolecules (carbohydrates, proteins, lipids) in aerobic respiration? Related to this question, why are fishes able to extract more energy from proteins than mammals or birds? Please be specific in your responses!

Metabolic stuff made once animal cells use carbohydrates are greenhouse gas and H2O, lipids - greenhouse gas and H2O, macro-molecule - carbamide and acid. Fish would like macro-molecule principally for growth. Fish eat to satisfy their energy demands. if the energy state of diet is a smaller amount, they waste macro-molecule to fulfill the metabolic desires, if energy state is high, it'll cut back the intake of food.