Fatty acids enter cellular respiration as

Options

A. one carbon fragment
B. two carbon fragments
C. three carbon fragments
D. long chain of 16 to 20 carbon atoms

Answer

**Step-by-Step Solution:**

1. **Understanding Fatty Acid Breakdown**: Fatty acids are components of fats and oils. When the body needs to utilize fats for energy, these fatty acids undergo a process called beta-oxidation.

2. **Beta-Oxidation Process**: During beta-oxidation, fatty acids are broken down in the mitochondria of cells. This process involves the removal of two-carbon units from the fatty acid chain.

3. **Formation of Acetyl CoA**: Each two-carbon fragment that is produced during beta-oxidation is converted into a molecule called Acetyl Coenzyme A (Acetyl CoA). This is a crucial step as Acetyl CoA is the molecule that enters the citric acid cycle (Krebs cycle) for further energy production.

4. **Entry into Cellular Respiration**: The Acetyl CoA then enters the citric acid cycle, where it is further oxidized to produce ATP, NADH, and FADH2, which are essential for cellular respiration.

5. **Conclusion**: Therefore, fatty acids enter cellular respiration as two-carbon fragments in the form of Acetyl CoA.

**Final Answer**: Fatty acids enter cellular respiration as **two-carbon fragments**.

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