| 1. | If fatty acids were to be respired they would first be degraded to acetyl CoA and enter the respiratory pathway. |
| 2. | Glycerol would enter the respiratory pathway after being converted to PGAL |
| 3. | Proteins and amino acids cannot enter the respiratory pathway |
| 4. | Because the respiratory pathway is involved in both anabolism and catabolism, it would hence be better to consider the respiratory pathway as an amphibolic pathway rather than as a catabolic one. |