Final Answer:
The given statement "The Krebs cycle takes place in five main steps" is false because the Krebs cycle, also known as the citric acid cycle or tricarboxylic acid (TCA) cycle, actually consists of eight main steps. Thus the correct option is B. False.
Step-by-step explanation:
The Krebs cycle, also known as the citric acid cycle or tricarboxylic acid (TCA) cycle, actually takes place in eight main steps, not five. This cycle is a crucial part of cellular respiration, occurring in the mitochondria of eukaryotic cells. It involves a series of chemical reactions that ultimately contribute to the production of ATP, the cell's primary energy currency.
In the first step of the Krebs cycle, acetyl-CoA (a two-carbon molecule derived from the breakdown of glucose) combines with oxaloacetate (a four-carbon molecule), forming citrate (a six-carbon molecule).
The subsequent steps involve a series of enzyme-catalyzed reactions that result in the regeneration of oxaloacetate, allowing the cycle to continue. Throughout these reactions, carbon atoms are released as carbon dioxide, and high-energy electrons are transferred to electron carriers.
The misconception of the Krebs cycle occurring in five steps might arise from a simplified understanding or confusion with other metabolic processes. Understanding the correct number of steps is crucial for grasping the complexity and significance of cellular respiration. The accurate knowledge of these processes is fundamental for students and professionals in biology, biochemistry, and related fields.
The given statement "The Krebs cycle takes place in five main steps" is false. Thus the correct option is B. False.