Date | May 2010 | Marks available | 3 | Reference code | 10M.3.HL.TZ1.14 |
Level | Higher level | Paper | Paper 3 | Time zone | Time zone 1 |
Command term | Compare | Question number | 14 | Adapted from | N/A |
Question
Define hormones.
State one type of hormone, giving an example.
Compare gastric juice and pancreatic juice.
Outline the reason for one named substance found in food not being digested and absorbed by humans.
Markscheme
chemical messengers secreted by endocrine glands/specialized cells directly into the blood/body fluid (and transported to specific target cells);
steroid hormone e.g. testosterone / peptide hormone e.g. insulin / tyrosine derivatives e.g. thyroxine;
Award [1] for each pair.
cellulose / lignin;
cellulase not present / no enzymes for digesting lignin;
Accept any other reasonable substance.
Examiners report
Most gave an incomplete definition of a hormone in (i) and therefore did not get the mark.
Part (ii) was often well-answered although some indicated the type of hormone as a sex hormone rather than stating it was a steroid hormone.
This was very poorly done by the majority of candidates. Those candidates that did know some facts about the two digestive juices did not make point by point comparisons despite the table provided. The table did seem to discourage better candidates from giving a similarity which would be expected for a comparison of two things. This was not penalized.
Many were able to get the 2 marks here for cellulose and lack of cellulose.