You might see the word alloy described as a mixture of metals, but that's a little bit misleading because some alloys contain only one metal and it's mixed in with other substances that are nonmetals (cast iron, for example, is an alloy made of just one metal, iron, mixed with one nonmetal, carbon).
Energy substrates in the human body are either carbohydrates, fat or proteins. Protein degradation yields amino acid residues which can be converted to carbohydrates and used in energy production. Carbohydrates (sugars) and amino acids from proteins give approximately 4 kcal/gram dry weight when burned in the body.
coenzymes are organic molecules that are required by certain enzymes to carry out catalysis. They bind to the active site of the enzyme and participate in catalysis but are not considered substrates of the reaction.coenzymes often function as intermediate carriers of electrons, specific atoms or functional groups that are transfered in the overall reaction.hey bind to the active site of the enzyme and participate in catalysis but are not considered substrates of the reaction. coenzymes often function as intermediate carriers of electrons, specific atoms or functional groups that are transfered in the overall reaction.