Question 21M.2.HL.TZ2.2a.iii
| Date | May 2021 | Marks available | [Maximum mark: 1] | Reference code | 21M.2.HL.TZ2.2a.iii |
| Level | HL | Paper | 2 | Time zone | TZ2 |
| Command term | Label | Question number | a.iii | Adapted from | N/A |
Cholinergic synapses use acetylcholine as their neurotransmitter. They are widespread in the body, passing on signals to muscle cells. These synapses are affected by neonicotinoid pesticides.
The diagrams, which are not drawn to scale, show the synapse between two neurons and a detail of the synaptic cleft.
On the diagrams, label with a letter P a location where a neonicotinoid pesticide could bind.
[1]
any receptor protein on post synaptic membrane marked ✔
For 2 a, i, ii and iii, accept letters written on the structure even if a line is not drawn.
Award the mark if the full word is used to label the structure.
Must unambiguously be pointed to a receptor on the synapse side. Accept labels of acetylcholinesterase.
Both receptor proteins and acetylcholinesterase were accepted as proteins to which acetylcholine can bind. The markscheme did not accept locations other than on the synaptic side.
