Carnitine, a zwitterionic compound derived from lysine, is involved in fatty acid metabolism and is required at which two points in the transport of fatty acids from the cytoplasm to the mitochondria (see Figure 3-5)
A: A and E
B: A and C
C: B and C
D: B and D
E: E and D
A: A and E
B: A and C
C: B and C
D: B and D
E: E and D
举一反三
- In fatty acid biosynthesis, which compound transports acetyl groups from the mitochondria into the cytoplasm？（） A: Coenzyme A B: Carnitine C: ACP D: Citric acid
- The synthesis of fatty acids USES carnitine to transport acetyl-CoA from the mitochondria to the cytoplasm.（）
- Some athletes believe that dietary carnitine supplements will enhance their ability to perform aerobic exercise. Which statement BEST describes the “scientific” basis of this belief? A: Carnitine is required in the transport of medium and long-chain fatty acids into the mitochondrial matrix, and so increasing the amount of carnitine will increase the rate of transport. B: Carnitine activates carnitine-acyl transferase-1 (CAT-I) thereby increasing the rate of transport of fatty acids into the mitochondrial matrix. C: Carnitine levels in the cytoplasm are reduced when large amounts of fatty acyl carnitine are transported into the mitochondrial matrix. D: Carnitine enhances the activation of fatty acids to fatty acyl-CoA, thereby increasing the rate of their transport into the mitochondrial matrix.
- Synthesis of fatty acids from acetyl CoA A: need NADPH B: need NAD+ C: produce malonyl CoA in the first step D: occur in mitochondria E: It's the reverse reactions of fatty acid oxidation
- What would be the consequences of inhibiting the carnitine shuttle which transports fatty acids into the mitochondria? A: accumulation of fat droplets in liver and muscle. B: Increase in blood glucose concentration. C: Increase in fatty acid synthesis in the liver. D: Low levels of long chain free fatty acids in the blood.