Which one of the following statements regarding bile secreted by liver is not correct?
- A.Bile contains enzymes for digestion of lipids.
- B.Bile facilitates emulsification of fats.
- C.Bile neutralizes the acidic pH of the food coming from stomach.
- D.Bile makes the pH of the food alkaline and facilitates action of pancreatic enzymes.
Correct answer
Explanation
The correct answer is A, Bile contains enzymes for digestion of lipids. Bile has no digestive enzymes at all; it only prepares fats for digestion by other enzymes.
Bile is made by the liver, stored and concentrated in the gall bladder, and poured into the duodenum through the bile duct. It contains water, bile salts, bile pigments (bilirubin and biliverdin), cholesterol and phospholipids, but no enzymes. Bile salts break large fat globules into tiny droplets, a process called emulsification, which gives the enzyme lipase from the pancreas a much larger surface to act on. Bile is also alkaline, which helps neutralise the acid coming from the stomach.
B is wrong: bile does emulsify fats, its main job, so this statement is correct.
C is wrong: bile is alkaline and helps neutralise the acidic food from the stomach, so this statement is correct.
D is wrong: by making the food alkaline, bile provides the medium pancreatic enzymes need, so this statement is correct.
Exam tip: bile = liver-made, gall bladder-stored, no enzymes; emulsifies fats for pancreatic lipase.
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