This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Link reaction, Subject name: Biochemistry
Malate shuttle is impoant in: 
Select and explain. 
A. Liver and Hea, B. Brain and Hea, C. Brain and Skeletal muscle, D. Liver and Skeletal muscle
A: Liver and Hea
Answer: A: Liver and Hea 
Explanation: Malate shuttle is more impoant in the liver and cardiac muscles as these organs require a continuous supply of energy. Whereas Glycerol-P-shuttle is a shoer shuttle and provides a quick source of ATPs as compared to the Malate shuttle. So it is present in brain & skeletal muscles, where energy is needed quickly in case of an emergency.