For the digestion of carbohydrate, protein and fat, enzymes such as amylase, trypsin and lipase are required. It is secreted into the duodenum through:
- A.Bile
- B.Plasma
- C.Lymph
- D.Pancreatic juice
Correct answer
Explanation
The correct answer is D, Pancreatic juice. The pancreas pours amylase, trypsin and lipase into the duodenum in its juice, so all three classes of food are digested there.
The pancreas is both an endocrine gland (insulin and glucagon) and an exocrine gland. Its exocrine part makes pancreatic juice, which reaches the duodenum through the pancreatic duct, joining the bile duct at the hepatopancreatic ampulla. The juice is alkaline because of bicarbonate, which neutralises the acid coming from the stomach. Pancreatic amylase turns starch into maltose, trypsin (secreted as inactive trypsinogen and activated by enterokinase) breaks proteins into peptides, and lipase splits fats into fatty acids and glycerol.
A is wrong: bile from the liver has no digestive enzymes; its salts only emulsify fats.
B is wrong: plasma is the liquid part of blood and does not enter the duodenum.
C is wrong: lymph is tissue fluid in the lymphatic system, not a digestive secretion.
Exam tip: pancreatic juice is the only juice that digests carbohydrates, proteins and fats; bile emulsifies fat but has no enzyme.
Practice Questions
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- C.tin
- D.aluminium
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- A.Hydrometer
- B.Hygrometer
- C.Hypsometer
- D.Pycnometer
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- A.Magnesium
- B.Iron
- C.Calcium
- D.Copper
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1. Detection of car crash/collision which results in the deployment of airbags almost instantaneously
2. Detection of accidental free fall of a laptop towards the ground which results in the immediate turning off of the hard drive
3. Detection of the tilt of the smartphone which results in the rotation of display between portrait and landscape mode
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- A.Only one
- B.Only two
- C.All three
- D.None
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1. Carbon fibres are used in the manufacture of components used in automobiles and aircrafts.
2. Carbon fibres once used cannot be recycled.
Which of the statements given above is/are correct?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
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