Question 19M.3.HL.TZ2.8
| Date | May 2019 | Marks available | [Maximum mark: 6] | Reference code | 19M.3.HL.TZ2.8 |
| Level | HL | Paper | 3 | Time zone | TZ2 |
| Command term | Discuss | Question number | 8 | Adapted from | N/A |
Discuss the effect of endorphins on the central nervous system (CNS) and in pain relief.
[6]
a. pain receptors/ends of sensory neurons send impulses to cerebral cortex creating sensation of pain ✔
b. endorphins interfere with neural transmission between areas of pain perception and CNS ✔
c. endorphins produced/secreted «primarily» by pituitary gland ✔
d. endorphins secreted during times of physical exercise/emotional stress ✔
e. endorphins bind to «opiate» receptors at «pre/post»synaptic membrane ✔
f. prevent neurotransmitters binding to postsynaptic membrane/cell ✔
g. decrease transmission at postsynaptic membrane
OR
are inhibitory neurotransmitters ✔
h. effects have slow onset but last long time «minutes/hours» ✔
i. act as natural painkiller
OR
produce feeling of euphoria ✔
Many had a vague idea about the effect of endorphins and limited their answers to a few memorized elements, not thinking about expanding their answer to their understanding of the nervous system at the cell or synapse level. A few excellent and extensive answers were nevertheless seen.
