Question 21M.2.HL.TZ2.2a.i
| Date | May 2021 | Marks available | [Maximum mark: 1] | Reference code | 21M.2.HL.TZ2.2a.i |
| Level | HL | Paper | 2 | Time zone | TZ2 |
| Command term | Label | Question number | a.i | 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 H the hydrophilic end of a phospholipid.
[1]
hydrophilic end of phospholipid shown ✔
For 2a, 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. Labels must be unambiguous.
There were numerous examples of ambiguous labels, for example, an H without an arrow placed beside the membrane making it unclear whether the student was indicating the hydrophobic or hydrophilic part of the membrane.
