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
Ammonia in brain is trapped by 
Select and explain. 
A. Alanine, B. Glutamine, C. Ornithine, D. Aspaate
B: Glutamine
Answer: B: Glutamine 
Explanation: Ans. is 'b' i.e.,Glutamine The brain is a rich source of glutamine synthase and predominantly detoxifies ammonia by synthesis of glutamine.Glutamate + NH4 - Glutamine sythetase - Glutamine