Answer: Binding to intrinsic factor secreted by gastric parietal cells.
- A Direct transport coupled to sodium-glucose cotransporters
- B Conjugation with bile salts in the duodenum
- C Binding to intrinsic factor secreted by gastric parietal cells
- D Hydrolysis by pancreatic amylase before uptake
Correct answer: C. Binding to intrinsic factor secreted by gastric parietal cells
Explanation: Vitamin B12 must bind intrinsic factor, secreted by gastric parietal cells, to form a complex that is recognized and absorbed by specific receptors in the ileum.
The human digestive system. Image: LadyofHats (Mariana Ruiz), Public Domain, via Wikimedia Commons.
Concept context
The digestive tract, digestive enzymes, hormonal control of digestion, and liver function. High NEET weightage.