Question: what are the 4 by-products (metabolites) of krebs cycle?
Answer: Products of the first turn of the cycle are one GTP (or ATP), three NADH, one QH2 and two CO2. Because two acetyl-CoA molecules are produced from each glucose molecule, two cycles are required per glucose molecule. Therefore, at the end of two cycles, the products are: two GTP, six NADH, two QH2, and four CO2.