DP Biology (first assessment 2025)
Question 22M.2.HL.TZ1.5c
| Date | May 2022 | Marks available | [Maximum mark: 2] | Reference code | 22M.2.HL.TZ1.5c |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | Describe | Question number | c | Adapted from | N/A |
c.
[Maximum mark: 2]
22M.2.HL.TZ1.5c
(c)
Describe the movements in ions that occur during time t.
[2]
Markscheme
Na+/sodium ions diffuse into the axon (in the first part/half of t);
K+ /potassium ions diffuse out of the axon (in the second half/part of t)
Do not accept the name of the element without indication that it is an ion.
Examiners report
Some candidates talked about ion movement but with no reference to a specific ion; some described the Na+/K+ pump here and received no marks.
