| Date | November 2016 | Marks available | 1 | Reference code | 16N.3.HL.TZ0.20 |
| Level | Higher level | Paper | Paper 3 | Time zone | TZ0 |
| Command term | Outline | Question number | 20 | Adapted from | N/A |
Question
The diagram demonstrates the action of steroid and peptide hormones in a section of cell and adjacent capillary.
On the diagram, label a
(i) second messenger.
(ii) gene regulatory protein.
Outline one characteristic of steroid hormones that allows them to readily diffuse through cell membranes
Compare and contrast the mechanisms of action of peptide and steroid hormones.
Markscheme
(i) a. second messenger correctly labelled
(ii) b. gene regulatory protein correctly labelled
Do not accept steroid hormone/protein complex.
a. lipid-soluble/non-polar/hydrophobic molecules «that readily diffuse through cell membranes»
b. small enough to diffuse through membrane
Since the questions asks to “outline” a brief account is necessary to gain the mark.
Answers do not need to be presented as a table. Award marks for pairs of corresponding elements on the same line of this table.
