I've done a couple of past papers and only seen it come up once or twice but I think they usually ask you to state one of them and maybe explain how it works.
my school skips these entirely for prelims so depending on the school it might not be that deep. maybe 1 question worth a few marks. in past papers i have seen questions that describe how a traditional practise of the ATSI peoples is done and ask what chemistry principles allow it to occur or smth like that. but then again they give you info and ask you to interpret it so even for that you might not need a deep understanding