How many ATP molecules are typically produced by one turn of the Krebs cycle?

Study for the DAT Quantitative Reasoning Test with multiple choice questions and detailed explanations. Hone your skills and get ready for your exam!

In one turn of the Krebs cycle, typically 1 ATP molecule is produced directly. This is achieved through substrate-level phosphorylation, where a phosphate group is transferred from a molecule to ADP, forming ATP. However, it’s important to note that while only one ATP is produced in terms of direct synthesis, the cycle also generates additional energetic compounds.

Specifically, during each turn of the Krebs cycle, 3 NADH and 1 FADH2 are produced as well. These two energetic molecules are crucial because they are later used in the electron transport chain, where they contribute to the generation of a significantly higher ATP yield through oxidative phosphorylation. Each NADH can produce approximately 2.5 ATP, and each FADH2 approximately 1.5 ATP when processed in the electron transport chain.

Thus, while the correct answer regarding direct ATP production per turn of the Krebs cycle is indeed 1 ATP, when considering the eventual ATP yield from NADH and FADH2, the broader context of ATP production reveals the cycle's importance in cellular respiration and energy production. This holistic view is crucial when studying the Krebs cycle in relation to overall cellular metabolism.

Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy