| Date | May 2017 | Marks available | 2 | Reference code | 17M.3.SL.TZ2.19 |
| Level | Standard level | Paper | Paper 3 | Time zone | Time zone 2 |
| Command term | Outline | Question number | 19 | Adapted from | N/A |
Question
The diagram shows a cell in the lining of the stomach.
Outline the importance of the proton pumps in the digestion of foods.
[2]
a.
Explain the use of proton pump inhibitors to treat patients complaining of stomach pain.
[3]
b.
Markscheme
a. pumps protons/H+ into the stomach
b. allows for the production of «hydrochloric» acid
c. «hydrochloric» acid accelerates digestion/activates enzymes
d. gives optimal pH for pepsin/enzyme digestion
a.
a. proton pump is a «transmembrane» protein
b. proton pump inhibitors bind to the proton pump
c. hydrogen ions are not sent into stomach lumen
OR
reduction of «gastric» acid production
d. increase in pH of stomach
e. relieve symptoms of acid reflux/gastritis/ulcers
b.
Examiners report
[N/A]
a.
[N/A]
b.
