It looks like this is a question about the products of the citric acid cycle (Krebs cycle), specifically the reductive (counterclockwise) path. The blanks currently filled with "FDA+" and "GTP" are incorrect. Here are the correct answers: - FADH₂ → succinate + **FAD** (not FDA+) - + 2 NAD⁺ + 2 H₂O + **ATP** (not GTP, though sometimes GTP is produced and then converted to ATP) So, the correct answers should be: 1. FAD (instead of FDA+) 2. ATP (instead of GTP) Let me know if you need an explanation of these steps!

Certainly! Here's a detailed two-step explanation with the correct answers and reasoning: **Step 1: Understanding the Reductive Path of the Citric Acid Cycle** In the Krebs cycle, specific steps involve reduction of coenzymes. The step involving FAD is the conversion of FAD to FADH₂ when succinate is oxidized to fumarate. This is a key point in the cycle's reductive pathway. **Explanation:** - When succinate is oxidized to fumarate, FAD acts as an electron acceptor, becoming FADH₂. - The reaction produces **FAD** (as the oxidized form), which is used to generate FADH₂ during the process. **Corrected Blank:** - **FAD** (not FDA+) --- **Step 2: Final Energy Product** In the cycle, substrate-level phosphorylation occurs during the conversion of succinyl-CoA to succinate, producing GTP, which can be readily converted to ATP. **Explanation:** - The direct product of this step is **GTP** (or sometimes ATP, depending on the organism). - Since the question emphasizes the reductive path and mentions ATP, it’s acceptable to note that GTP can be converted into ATP in the cell. **Corrected Blank:** - **ATP** (instead of GTP) --- **Final Answer:** 1. **FAD** 2. **ATP** This clarifies that the reductive (counterclockwise) pathway involves the formation of FADH₂ from FAD and the production of ATP via substrate-level phosphorylation.