List the functions of the liver (60% marks).
Discuss the metabolism of paracetamol in toxicity and the pharmacologic management of this overdose (40% marks).
A good response to this question required an ordered and well structured response. There are numerous important functions that the liver undertakes (eg bile formation, immunological, protein, lipid, glucose metabolism, storage, endocrine, etc), yet most candidates could not generate a sufficient list. In relation to paracetomol toxicity, a good response required candidates to mention that normal conjugating reactions in the liver are saturated and metabolism diverts to mixed function oxidases, which generate toxic metabolites. These in turn are inactivated by conjugation with glutathione. However when glutathione is depleted, toxic metabolites react with cellular nuclear material, thus causing liver necrosis. Toxic compound depletes sulphydril groups and also causes direct damage via lipid peroxidation. Regeneration of sulphydril groups and glutathione depends on availability of cysteine, thus the need to administer acetylcysteine.
You have a maximum of six minutes to list all the functions of the liver, which is probably why "most candidates could not generate a sufficient list". Considering that the highest possible rate of writing legible handwritten characters is approximately 190 characters per minute (by a 1980s police interviewer, a group widely held to be the fastest handwriters in the universe), this limits the list to a maximum of 1,140 characters, excluding blank spaces. Working within this framework, the absolutely maximally comprehensive answer to the first part of this question should look something like this:
That's 146 words, or 1,140 characters. Now: to paracetamol.
Kuntz, Erwin, and Hans-Dieter Kuntz. "Biochemistry and functions of the liver." Hepatology Textbook and Atlas: History· Morphology Biochemistry· Diagnostics Clinic· Therapy (2008): 35-76.
Ozougwu, Jevas C. "Physiology of the liver." International Journal of Research in Pharmacy and Biosciences 4.8 (2017): 13-24.