Question 19M.3.HL.TZ2.20c
| Date | May 2019 | Marks available | [Maximum mark: 3] | Reference code | 19M.3.HL.TZ2.20c |
| Level | HL | Paper | 3 | Time zone | TZ2 |
| Command term | Outline | Question number | c | Adapted from | N/A |
Most stomach ulcers are caused by a bacterium that lives under the mucus lining of the stomach wall.
This organism causes the production of reactive compounds which result in oxidation. This makes the ulcer progress and, consequently, healing is more difficult. A study was carried out to compare the effect of the drug nizatidine (N) alone or combined with the antioxidants vitamin E and thioctic acid.
[Source: Effect of Helicobacter Pylori Eradication Therapy and some Antioxidants on Ulcer Healing Rates
in Patients with Helicobacter pylori-associated Duodenal Ulcer, Ahmed M Ali, 2013, http://www.rroij.com/
open-access/effect-of-helicobacter-pylori-eradication-therapy-and-some-antioxidants-on-ulcer-healingrates-
in-patients-with-helicobacter-pylor-.php?aid=34774, licensed under a
Creative Commons Attribution 4.0 International License]
Components of gastric juice have been thought to aggravate the development of ulcers. Outline the role of nerves in the secretion of gastric juices.
[3]
a. sight/smell of food stimulates brain ✔
b. food entering stomach stimulates chemoreceptors/stretch receptors to send impulses/signals to brain ✔
c. impulse/signal from brain causes cells in stomach lining/parietal cells to secrete acid/HCl/gastric juice ✔
d. brain sends impulses/signals «via vagus nerve» to endocrine cells in wall of stomach to release gastrin ✔
e. gastrin stimulates «more» production of acid/HCl/gastric juice ✔
The majority had a good idea about factors that would increase gastric juice secretion, but a large number bypassed the role of the brain or the nerves in their answer, limiting themselves to the various stimuli and responses.
