DP Biology (last assessment 2024)
Question 20N.3.HL.TZ0.c
| Date | November 2020 | Marks available | [Maximum mark: 1] | Reference code | 20N.3.HL.TZ0.c |
| Level | HL | Paper | 3 | Time zone | TZ0 |
| Command term | Suggest | Question number | c | Adapted from | N/A |
c.
[Maximum mark: 1]
20N.3.HL.TZ0.c
The image on the left shows a developing neuron on the first day of culture (day 1). The image on the right shows the same neuron after one day (day 2).
[Source: The establishment of polarity by hippocampal neurons
in culture, CG Dotti, CA Sullivan and GA Banker, Journal of Neuroscience 1 April 1988, 8 (4) 1454–1468;
DOI: https://doi.org/10.1523/JNEUROSCI.08-04-01454.1988, Copyright ©1988 Society for Neuroscience.]
Suggest what can happen to neurons that are unused in the nervous system.
[1]
Markscheme
a. neural pruning;
b. neurons are destroyed / apoptosis
Examiners report
The vast majority of candidates correctly suggested neural pruning.
