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
Amino acid absorption is by- 
Select and explain. 
A. Facilitated transpo, B. Passive transpo, C. Pinocytosis, D. Active transpo
D: Active transpo
Answer: D: Active transpo 
Explanation: Free amino acids are absorbed across the intestinal mucosa by sodium-dependent active transpo. There are several different amino acid transpoers, with specificity for the nature of the amino acid side-chain. Transpoers of Amino Acids. For Neutral Amino Acids For Basic Amino acids and Cysteine For Imino Acids and Glycine For Acidic Amino Acids For Beta Amino Acids (Beta Alanine) Meisters Cycle For absorption of Neutral Amino acids from Intestines, Kidney tubules and brain. The main role is played by Glutathione. (GSH) For transpo of 1 amino acid and regeneration of GSH 3 ATPs are required.