This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
The mechanism by which cytosol pyruvate is transported to mitochondria is 
Select and explain. 
A. Chloride antiport, B. Proton symport, C. ATP dependent antiport, D. Facilitated uniport
B: Proton symport
Answer: B: Proton symport 
Explanation: Pyruvate is formed from glucose oxidation (glycolysis) in cytosol.
It is transported into the mitochondria along with Er (proton) symport by a monocarboxylate carrier.