Final answer:
Carbon dioxide (CO2) is the blood gas produced from the metabolism of carbohydrates, lipids, and proteins, released as a byproduct of ATP generation in metabolic pathways.
Step-by-step explanation:
The blood gas produced from the metabolism of carbohydrates, lipids, and proteins is carbon dioxide (CO2). Metabolism of these macronutrients involves complex pathways where carbohydrates are broken down through glycolysis and the Krebs cycle, lipids through ß-oxidation and also the Krebs cycle, and proteins by way of deamination. During these metabolic processes, the ATP is generated, and CO2 is produced as a waste product. For instance, when glucose from carbohydrates undergoes glycolysis, it eventually leads to the creation of pyruvate that enters the Krebs cycle producing CO2.
Similarly, the breakdown of fats into glycerol and fatty acids or the deamination of amino acids during protein metabolism yields molecules that enter various metabolic cycles also producing ATP and CO2.