DP Chemistry (last assessment 2024)
Question 19N.3.sl.TZ0.16c
Date | November 2019 | Marks available | [Maximum mark: 1] | Reference code | 19N.3.sl.TZ0.16c |
Level | sl | Paper | 3 | Time zone | TZ0 |
Command term | Outline | Question number | c | Adapted from | N/A |
c.
[Maximum mark: 1]
19N.3.sl.TZ0.16c
Body fluids have different pH values.
(c)
Outline how ranitidine reduces stomach acidity.
[1]
Markscheme
blocks/binds to H2-histamine receptors «in cells of stomach lining»
OR
prevents histamine molecules binding to H2-histamine receptors «and triggering acid secretion»
OR
prevents parietal cells from releasing/producing acid ✔
NOTE: Do not accept “antihistamine” by itself.
Accept “H2-receptor antagonist/H2RA” OR “blocks/inhibits action of histamine”.
Accept “blocks receptors in parietal cells «from releasing/producing acid»”.
Do not accept “proton pump/ATPase inhibitor”.
