DP Chemistry (last assessment 2024)
Question 19N.3.hl.TZ0.a
Date | November 2019 | Marks available | [Maximum mark: 2] | Reference code | 19N.3.hl.TZ0.a |
Level | hl | Paper | 3 | Time zone | TZ0 |
Command term | Explain | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 2]
19N.3.hl.TZ0.a
Changes in physiology can impact living creatures.
The graph shows the change in oxygen partial pressure in blood, measured at different pH values.
Explain the effect of changing pH on the percentage saturation of hemoglobin at a given partial pressure of oxygen.
[2]
Markscheme
as pH decreases, protons/CO2 bind to allosteric sites
OR
as pH decreases, protons/CO2 act as non-competitive inhibitor
OR
active/binding site changes shape ✔
saturation decreases
OR
more oxygen released
OR
affinity to oxygen decreases ✔
