UPSC Prelims 2003 Q129: Science & Technology – Biology
With reference to normal human beings, consider the following statements:
1. In response to the presence of HCl, secretin is produced from the duodenum
2. Enterogastrone is produced in the small intestine in response to the presence of fatty acids
Which of these statements is/are correct?
- (a) Only 1
- (b) Only 2
- (c) Both 1 and 2
- (d) Neither 1 nor 2
Answer: (c) Both 1 and 2
Explanation
Digestive hormones
| Statement | Verdict |
|---|---|
| 1. Secretin is produced from the duodenum in response to HCl | True |
| 2. Enterogastrone is produced in the small intestine in response to fatty acids | True |
Both statements are correct: secretin from the duodenum stimulates pancreatic juice in response to acid, and enterogastrone (gastric inhibitory hormone) is released by fats.
Answer: (c) Both 1 and 2.
Why each option is right or wrong
- (a) Incorrect. Statement 2 is also correct.
- (b) Incorrect. Statement 1 is also correct.
- (c) CORRECT. Both statements are correct.
- (d) Incorrect. Both statements are correct.
Key point
Secretin: acid, bicarbonate; CCK: fats, enzymes; gastrin: stomach acid; enterogastrone: inhibits gastric secretion.
Remember
HCl in the duodenum triggers secretin.
Common mistakes
- Placing secretin in the stomach.
- Mixing enterogastrone with gastrin.
- Forgetting about CCK from the duodenum.
Exam tip
Secretin was the first hormone discovered (1902).
Sources
- NCERT Class XI Biology — Digestion and Absorption
- John E. Hall — Guyton and Hall Textbook of Medical Physiology (Secretory Functions of the Alimentary Tract)