Final answer:
The correct answer is that in the glyoxylate cycle, two acetyl CoA molecules are used to generate succinate. This cycle differs from the citric acid cycle by bypassing the decarboxylation steps and is used by plants and bacteria to convert fats into carbohydrates.
Step-by-step explanation:
The student asked which statement accurately describes the citric acid cycle and the glyoxylate cycle. The correct answer is C) In the glyoxylate cycle, two acetyl CoA molecules are used to generate succinate. This cycle bypasses the decarboxylation steps of the citric acid cycle, allowing organisms, especially plants and bacteria, to convert fats into carbohydrates.
The citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, operates in the matrix of mitochondria and goes through a series of redox, dehydration, hydration, and decarboxylation reactions. The cycle is a closed loop that culminates in the regeneration of oxaloacetate, which combines with acetyl CoA to begin the cycle again. Each turn of the citric acid cycle generates GTP/ATP, and electrons are transferred to NADH and FADH₂ for use in oxidative phosphorylation.
The glyoxylate cycle is a variation present in plants and bacteria, which allows the conversion of fatty acids into carbohydrates. The cycle bypasses the two decarboxylation steps of the citric acid cycle where CO₂ is produced, resulting in net carbohydrate synthesis. Only one of the statements provided (C) correctly addresses the glyoxylate cycle's unique feature of using two acetyl CoA molecules to generate succinate without the loss of carbon as CO₂.