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: Physiology
Iron absorption occurs from 
Select and explain. 
A. Ileum, B. Small intestine and jejunum, C. Stomach, D. Oesophagus
B: Small intestine and jejunum
Answer: B: Small intestine and jejunum 
Explanation: Almost all iron absorption occur in duodenum & upper jejunum (proximal small intestine). Absorption of the majority of nutrients takes place in the jejunum, with the following notable exceptions: Vitamin B12 and bile salts are absorbed in the terminal ileum. Water and lipids are absorbed by passive diffusion throughout the small intestine. Sodium bicarbonate is absorbed by active transport and glucose and amino acid co-transport. Fructose is absorbed by facilitated diffusion.