Final answer:
The Krebs (TCA) cycle takes place in the matrix of the mitochondria, and almost all of its enzymes are soluble and located there, except for succinate dehydrogenase, which is embedded in the inner mitochondrial membrane. The cycle creates energy carriers that fuel the electron transport chain in the mitochondrion's inner membrane.
Step-by-step explanation:
The correct answer to the question 'All enzymes of the Krebs (TCA) cycle except ……………… are located ………………?' is 'Enzyme B, in the mitochondria'.
The Krebs cycle, also known as the citric acid cycle or tricarboxylic acid (TCA) cycle, takes place in the matrix of the mitochondria. It is a series of redox and decarboxylation reactions that generate energy-carrying molecules like ATP, NADH, and FADH₂. With the solitary exception of the enzyme succinate dehydrogenase, which is integral to the inner mitochondrial membrane, all other enzymes in the Krebs cycle are soluble and located in the mitochondrial matrix. The energy from the NADH and FADH₂ produced is transferred to the electron transport chain, which is located in the inner membrane of the mitochondrion and is essential for aerobic respiration.
This transfer is vital because without it, the citric acid cycle would not proceed. However, it's important to note that the cycle itself does not directly use oxygen nor does it produce a significant amount of ATP directly. Instead, it produces molecules that are then used in the electron transport chain to produce ATP through oxidative phosphorylation, also occurring in the mitochondria.