LIFE SCIENCES Paper 2 Memo (Eng) November 2009

Life Sciences/P2 11 DoE/November 2009NSC – MemorandumNOTE:If the wrong type of graph is drawn:- Marks will be lost for ‘correct type of graph’- Marks will be lost for ‘joining of points’If graphs are not drawn on the same system of axes:- Mark the first graph only using the given criteriaIf axes are transposed:- Marks will be lost for labelling of ‘X-axis’ and ‘Y-axis’4.2 4.2.1 Lives in shallow waterDoes not need expensive fishing equipmentEasy to removeSessile/don't move(Mark first TWO only) any (2)4.2.2 - Limit the number caught- Only licensed fishermen may catchperlemoen- Stipulate minimum size of perlemoen thatcan be caught- Impose seasonal limitations- Heavy penalties/fines for those whocontravene regulations- Declare as a protective species- Patrol all beaches where perlemoen isfound- Improve education/awareness- Encourage perlemoen farming/mariculture- Establish marine protected areas(Mark first TWO only)- Introducestrictlegislationany(2)4.2.3 The perlemoen is a herbivore/occupies the second trophic levelIf the number of perlemoen is reduced:Energy at the first trophic level /algae that the perlemoen feedson, will increasebecause of decreased demand for algae / food by perlemoen.There will also be a decrease in the energy at the third trophiclevel/ organisms feeding on perlemoenbecause of decrease in food supply (perlemoen) available tothem.The energy flow through the habitat will thus be reducedany (3)(7)Copyright reservedPlease turn over