Identify each pathway as anabolic or catabolic
b. citric acid cycle

Verified step by step guidance

1. Understand the definitions of anabolic and catabolic pathways: Anabolic pathways involve the synthesis of complex molecules from simpler ones, requiring energy input. Catabolic pathways involve the breakdown of complex molecules into simpler ones, releasing energy.
2. Recall the purpose of the citric acid cycle (also known as the Krebs cycle or TCA cycle): It is a central metabolic pathway that breaks down acetyl-CoA into carbon dioxide while generating high-energy molecules like NADH and FADH2.
3. Analyze the process: The citric acid cycle involves the degradation of acetyl-CoA, which is a complex molecule, into simpler molecules (CO2) and the production of energy-rich compounds.
4. Determine the classification: Since the citric acid cycle is primarily involved in breaking down molecules and releasing energy, it is classified as a catabolic pathway.
5. Conclude that the citric acid cycle is a catabolic pathway based on its role in energy production and molecular breakdown.

Key Concepts

Anabolic Pathways

Anabolic pathways are metabolic processes that build larger molecules from smaller ones, requiring energy input. These pathways are essential for growth, repair, and the synthesis of complex biomolecules like proteins, nucleic acids, and lipids. An example of an anabolic process is protein synthesis, where amino acids are linked together to form proteins.

Catabolic Pathways

Catabolic pathways are metabolic processes that break down larger molecules into smaller ones, releasing energy in the process. This energy is often captured in the form of ATP, which cells use for various functions. An example of a catabolic process is cellular respiration, where glucose is broken down to produce energy.

Citric Acid Cycle

The citric acid cycle, also known as the Krebs cycle, is a key metabolic pathway that plays a central role in cellular respiration. It is primarily catabolic, as it breaks down acetyl-CoA derived from carbohydrates, fats, and proteins into carbon dioxide and high-energy electron carriers. These carriers then enter the electron transport chain to produce ATP, highlighting the cycle's importance in energy production.