Which of the following statements regarding metabolism is false? Heat may be released in both anabolic and catabolic reactions. Atp is formed in catabolic reactions. Adp is formed in anabolic reactions. anabolic reactions are degradative.
The Correct Answer and Explanation is:
The false statement is: “Anabolic reactions are degradative.”
Explanation:
Metabolism refers to all the chemical reactions in the body that are involved in maintaining life, and it can be broken down into two main categories: catabolism and anabolism.
- Catabolic Reactions (Degradative Reactions):
- These reactions break down complex molecules into simpler ones, releasing energy in the process. This energy is often captured in the form of ATP (adenosine triphosphate).
- For example, the breakdown of glucose during glycolysis and cellular respiration to produce ATP is a catabolic process.
- Heat is often released during these reactions as a byproduct because they involve the breakdown of high-energy bonds in larger molecules, such as proteins, fats, and carbohydrates.
- Anabolic Reactions (Biosynthetic Reactions):
- Anabolic reactions, in contrast, are constructive, meaning they build complex molecules from simpler ones, requiring energy input to occur.
- These reactions include processes such as protein synthesis, where amino acids are linked together to form proteins, and DNA replication, where nucleotides are linked to form the DNA molecule.
- Since these processes require energy, they typically use ATP (not ADP) to drive the reaction. Therefore, the statement that “ADP is formed in anabolic reactions” is inaccurate; anabolic reactions consume ATP rather than produce ADP.
- Anabolic reactions are not degradative, they are synthetic, requiring energy to create larger, more complex molecules.
- Energy Transfer:
- ATP, which is synthesized during catabolic reactions, is used as the energy currency for anabolic reactions. ATP contains high-energy bonds between its phosphate groups, which, when broken, release energy.
- The release of heat in both anabolic and catabolic reactions is due to the release of energy as chemical bonds are broken or formed, but the energy profile differs in terms of whether it is used (anabolism) or released (catabolism).
Thus, the false statement in the question is “anabolic reactions are degradative,” as anabolic reactions are constructive and require energy input, in contrast to catabolic reactions, which are degradative and release energy.