Life Sciences Grade 11 P2 Eastern Cape November 2015 Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 11 NOVEMBER 2015 LIFE SCIENCES P2 MEMORANDUM MARKS: 150 TIME: 2½ hours This memorandum consists of 9 pages.

Downloaded from hlayiso.com 2 LIFE SCIENCES P2 (EC/NOVEMBER 2015) SECTION A QUESTION 1 1.1 1.1.1 A  1.1.2 A  1.1.3 B  1.1.4 C  1.1.5 D  1.1.6 D  1.1.7 C  1.1.8 D  1.1.9 D  1.1.10 B  (10 x 2) (20) 1.2 1.2.1 Symmetrical /bilaterally symmetrical / radially symmetrical 1.2.2 Sporangia / sporangium 1.2.3 Mesoglea  1.2.4 Deforestation  1.2.5 Ozone  1.2.6 Cephalisation  1.2.7 Binary fission  1.2.8 Mesoderm  1.2.9 Biodegradable  1.2.10 Erosion  (10 x 1) (10) Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) LIFE SCIENCES P2 3 1.3 1.3.1 B only  1.3.2 Both A and B  1.3.3 B only  1.3.4 Both A and B  1.3.5 B only  1.3.6 A only  1.3.7 A only  1.3.8 A only  (8 x 2) (16) 1.4 1.4.1 (a) 2014  (1) (b) 1994  (1) 1.4.2 (a) 9 – 10  (1) (b) 17 – 18  (1) TOTAL SECTION A: 50 Copyright reserved Please turn over

Downloaded from hlayiso.com 4 LIFE SCIENCES P2 (EC/NOVEMBER 2015) SECTION B QUESTION 2 2.1 2.1.1 Wind  (1) 2.1.2 - Produces large amount of pollen  to increase the chances of pollination. - Pollen grains are light, smooth  and dry to allow them to float. - Anthers are attached to their filaments in such a way that they are easily moveable with wind.  - Stigma is large, feathery and sticky to trap as much pollen as possible. - Large anther - Small flowers without colourful petals. - Absence of petals / calyx for better exposure of pollen to wind. - Reduced scent and nectar. (Any 3 x 1) (3) 2.2 2.2.1 - It generates genetic variety.  (1) 2.2.2 - (120 – 90 = 30)  (30/120 x 100 = 25%)  (2) 2.2.3 (a) They survive unfavourable periods./Testa protects the embryo.  (b) Provides food for the growing embryo  until the plant starts to make food by means of photosynthesis. (2) 2.3 2.3.1 Algae  (1) 2.3.2 Angiosperms  (1) 2.3.3 Gymnosperm  Angiosperm  (2) 2.4 2.4.1 - In low income group it remained the same  - Low middle income group it remained the same  - Upper middle income group it increased by 10 per 1 000 000  - High income group it decreased by 3 per 1 000 000  (4) 2.4.2 - Overcrowded living space  - Poorly ventilated living space  - Poor diet /malnourished - Poor health / more diseases like HIV / less immunity - Homelessness / poverty - Medical treatment more difficult to access.  - Lack of awareness / Lack of education (Any 3 x 1) (3) Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) LIFE SCIENCES P2 5 2.5 2.5.1 - Carbon dioxide  and methane  (2) 2.5.2 - It traps sufficient heat to sustain life. / keeps temperature at favourable range. - Radiant energy is used for various life processes, such as photosynthesis.  (2) 2.5.3 - Burning fossil fuels  - Land clearing / deforestation (Accept any sensible answer) (Any 1 x 1) (1) 2.5.4 - Natural greenhouse effect releases more infrared rays  into the atmosphere than enhanced greenhouse effect.  OR - Natural greenhouse effect has less greenhouse gases  surrounding the atmosphere than enhanced greenhouse effect.  (2) 2.6 2.6.1 - Faecal coliforms,  nitrates  phosphates  (3) 2.6.2 - Not functioning properly,  because the level of faecal coliforms increased greatly from sample A to sample B,  indicating that untreated wastewater is being released into the river.  (3) 2.6.3 - Cholera,  typhoid,  hepatitis,  gastroenteritis, dysentery  / diarrhoea ect. (Any 2 x 1) (2) 2.6.4 - More acidic.  (1) 2.6.5 - Drainage of highly acidic water  from old mine shafts to the surface of the land.  (2) 2.6.6 - Toxic levels of salts (sodium and chloride)  - Reduced oxygen levels  caused by the decomposition of water plants that grew rapidly due to eutrophication. - pH level dropping / water too acidic for fish to survive. (Any 2 x 1) (2) [40] Copyright reserved Please turn over

Downloaded from hlayiso.com 6 LIFE SCIENCES P2 (EC/NOVEMBER 2015) QUESTION 3 3.1 3.1.1 - To find out which method of drying is better – air blowing or towel drying.  OR - To investigate the effect of two different methods of drying hands, after washing, on the number of bacteria on the skin of the hands.  (1) 3.1.2 - The atmospheric temperature / humidity in the testing venue.  - The time of wiping and exposure to the hot air.  - Using the same people for both methods.  - Using the same conditions for washing (e.g. amount of soap, amount of water, time rinsing, etc.)  (Any 3 x 1) (3) 3.1.3 - Air-dried skin samples have a far greater number of bacteria compared to towel-dried skin samples.  OR - Towel drying is better than air blow drying.  (1) 3.1.4 Graph showing number of bacteria on four samples of towel dried skin 1.2 1.11 Number of bacteria (x108/cm2) 1.02 0.98 1 0.8 0.6 0.42 0.4 0.2 0 1 2 3 4 Sample Guideline for the assessing of the graph Correct type of graph 1 Title of graph 1 Correct label and scale of x-axis 1 Correct label and scale of y-axis 1 Plotting of bars 1 : 1 to 3 bars plotted correctly 2 : all 4 bars plotted correctly (6) NOTE: If axes are transposed, marks will be lost for labelling X- axis and Y-axis. Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) LIFE SCIENCES P2 7 3.2 3.2.1 (a) photosynthesis  (1) (b) respiration  (1) 3.2.2 - Leads to an increase in the temperature of the atmosphere  (1) 3.2.3 - Global warming  (1) 3.2.4 - Something that absorbs carbon dioxide from the atmosphere.  (1) 3.2.5 - Green plants  - Trees / timber - Forests  (Any 1 x 1) (1) 3.2.6 - Levels of carbon dioxide in the atmosphere would rise.  (1) 3.3 3.3.1 - Harvesting from a different section of the harvest area each time.  (1) 3.3.2 - Gives the plant a chance to grow  (1) 3.3.3 - Rotational harvesting is a more sustainable method of harvesting Devil’s Claw.  OR - Regular harvesting is more sustainable  method of harvesting Devil’s Claw / both are equally  sustainable.  (2) 3.3.4 Rotational harvesting Regular harvesting 2007 8 9 2008 9 4 *Correct heading of columns = 1 *Correct heading of rows = 1 *Correct entering of data = 2 (4) 3.3.5 - Rotational harvesting is sustainable  regular harvesting is not. / rotational harvesting is more sustainable.  (2) 3.4 3.4.1 - Cnidaria  (1) 3.4.2 - Radial symmetry (1) 3.4.3 - It can catch prey / sense danger from all directions, because they are sedentary / sessile. (2) 3.4.4 - Chordata;  Arthropoda;  Annelida  (3) 3.5 3.5.1 - Antibodies  (1) Copyright reserved Please turn over

Downloaded from hlayiso.com 8 LIFE SCIENCES P2 (EC/NOVEMBER 2015) 3.5.2 - Antibodies remain in the body / are not weakened / last for a long time or are not destroyed / body continues to make antibodies / cause an increase in the number of antibodies / person has made own antibodies. (Any 1 x 1) (1) 3.5.3 - Antibodies are weakened after a short time / antibodies are made in an animal body / they are not human antibodies / person has not made own antibodies. (Any 1 x 1) (1) 3.5.4 - So that more antibodies are made / to keep antibody count high / so body keeps making antibodies for a long time. (Any 1 x 1) (1) 3.5.5 - Injection of ready-made antibodies / does not have to wait for antibody formation / has large amount of antibody quickly available / antibodies start working straight away. (Any 1 x 1) (1) [40] TOTAL SECTION B: 80 SECTION C QUESTION 4 4.1 Food security. - The state of having reliable access  to a sufficient quantity of affordable, nutritious food.  (2) Poor crop farming practices - monoculture  planting the same crop over and over  - because it is cost effective , but - it attracts more pests  and it - reduces quantity of crop produced  - this makes food more expensive to buy / less affordable - pest reduce the quality of crop  making - it necessary to use more pesticides,  more money spent - pesticides / insecticides kill useful crops also  - pesticides are bad for human health / affects nerves - they also cause pollution  and it - also reduces biodiversity  - monoculture causes top soil erosion,  leading to - more fertilisers to be used  - over fertilisation causes oxygen deprived soil  - leads to less production of crops  in future - and also produces greenhouse gases  - poor irrigation / poor infrastructure used due to - lack of awerness / education / experience / motivation Max. (10) Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) LIFE SCIENCES P2 9 Genetically modified food - genes for desired traits are removed  from one plant and - introduced into another plant  to make better crop - examples of desired traits – resistance to diseases  - short maturity  - higher yield  - cheaper food  - increases nutritional value  - longer shelf life  - bigger and more attractive food, etc. - helps poor / starving / famine people  - to make food accessible and available  Max. (5) (17) Relevance (R) Logical Sequence (L) Comprehensive (C) All information provided Ideas are arranged in a In the body of the are relevant to the logical manner i.e essay, minimum 6 essay i.e only the 3 starting with food relevant points out of points are discussed. security followed by the 10 for poor farming poor crop farming practices and a practices followed by minimum of 3 points for genetically modified genetically modified food. food are obtained. Synthesis (3) TOTAL SECTION C: 20 GRAND TOTAL: 150 Copyright reserved Please turn over