11 . G11 LifeSciences DigitalSupport web Practice Examination Paper 2 Memo

Study & Master Support Pack | Grade 11 CAPS Life Sciences Practice examination: Paper 2 memo This support pack consists of a memorandum of answers for Paper 2 of the Life Sciences Grade 11 CAPS curriculum so that you or the learners can check their answers and asses their readiness for the examinations. You have permission to print or photocopy this document or distribute it electronically via email or WhatsApp. Cambridge University Press Africa is a proudly South African publisher. For more information on our Study & Master CAPS-approved textbooks and valuable resource materials, visit www.cambridge.org Brighter thinking | Better learning Practice Examinations Paper 1: Memo www.cambridge.org

Life Sciences Examination: Exemplar Paper 2 2.1.3 a b A and C (2) Both antibiotics A and C do not destroy any bacteria, Memorandum of answers which you can see because there is no clear area without bacterial growth. (2) Marks: 150 2.1.4 a Fungal spores could act like an antibiotic. Time: 2 ½ Hours (2) b Fungal spores could cause fungal diseases. (2) [13] Section A 2.2 QUESTION 1 2.2.1 • Wear rubber gloves when taking the samples so as not to 1.1 get contaminated with germs 1.1.1 c • Samples should be taken by using a container/bottle 1.1.2 a attached to a string to avoid stepping too close to 1.1.3 c the river bank/prevent drowning/falling into water/ 1.1.4 b contamination (4) 1.1.5 c 2.2.2 Temperature of the human body at which the bacterium 1.1.6 c normally lives/E. coli normally lives in large intestinal 1.1.7 b (7 × 2) [14] of humans/human body temperature is 37 ˚C/ to allow bacteria to reproduce (2) 1.2 2.2.3 River Y (1) 1.2.1 cephalisation 2.2.4 The chemical indicator changed to a cloudy yellow 1.2.2 prokaryote colour, which indicates the presence of E. coli/which 1.2.3 pathogen is a positive test for E. coli (2) 1.2.4 mycelium 2.2.5 Lack/absence of proper sewage systems/poor hygiene/ 1.2.5 thallus bacteria in water results in faeces getting into water (2) 1.2.6 mutualism [11] 1.2.7 capsid 1.2.8 through gut 2.3 1.2.9 fruit 2.3.1 Hydra sp. – radial symmetry 1.2.10 spore Planaria sp. – bilateral symmetry (2) 1.2.11 rhizome 2.3.2 • sessile organism (11 × 1) [11] • does not go in search of food • mouth centrally situated 1.3 • tentacles in a ring all around 1.3.1 Both a and b • sensory cells all around 1.3.2 b only • these detect and capture food from all sides (3) 1.3.3 b only 2.3.3 Hydra sp. 1.3.4 b only • diploblastic 1.3.5 a only • rapid diffusion of food (5 × 2) [10] • many phagocytic cells all over endoderm • distribution made easier. 1.4 Planaria sp. 1.4.1 A, B, H, I, K • diverticulated gut that branches throughout the body 1.4.2 C, E • caeca present 1.4.3 G • all cells close to food supply 1.4.4 J • flattened form makes diffusion easier 1.4.5 B, H, I, K • phagocytic cells all over gut lining. (6) 1.4.6 I, K 2.3.4 • yes – earthworm has a through gut [10] • no mixing of food to be ingested and egested • gut has become specialised 1.5 • parts e.g. crop, gizzard perform specific functions 1.5.1 C – Petal /corolla • systemic processing of food. (5) D – Anther [16] E – Stigma (3) 2.4 1.5.2 B (1) 2.4.1 Logistic growth form (1) 1.5.3 B (1) 2.4.2 A = lag/establishment phase [5] B = exponential /geometric/accelerating/log/ logarithmic phase Total section A: [50] C = equilibrium/stationary/stabilising/constant phase (3) 2.4.3 B (1) QUESTION 2 2.4.4 • Environmental resistance increased 2.1 • causing the carrying capacity of the area to be reached 2.1.1 Antibiotic B is more effective in destroying bacteria than • leading to increased competition antibiotic F or antibiotic B has a larger area without • resulting in the death rate increasing to equal the birth bacterial growth compared to antibiotic F. (2) rate 2.1.2 a E (1) • or resulting in increased emigration that balances with b Antibiotic E is the next most effective antibiotic after immigration (3) antibiotic B, which you can see from the second largest zone of no bacterial growth. (2) Practice Examinations Paper 1: Memo

2.4.5 • Population is acclimatising/adapting to its new Drawing of the graphs 1: 1 to 8 points plotted correctly environment 2: 9 to 15 points plotted correctly • Few pairing partners 3: all 16 points plotted accurately • Time required for producing offspring is relatively long (12) • Not all individuals are sexually mature Note: (mark TWO only) (2) If the wrong type of graph is drawn: [10] • 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: Total question 2: [50] • mark the first graph only using the given criteria If axes are transposed: QUESTION 3 • marks will be lost for labelling of x-axis and y-axis 3.1 3.2.2 Herring population shows a sharp decline from year 3.1.1 Africa (1) 1 to 2 and then a steady decline until year 7 and then 3.1.2 547 793 × 100 small increase any (4) 3 084 746 1 3.2.3 Any two of: = 17,8 accept (17,7–17,8) (3) • Limit the size of fish caught 3.1.3 Trees used for: • Limit the number/quotas of fish caught • fuel/fire • Limit the fishing area • building houses • Licence to fish • space for human settlements/farming/livelihood • Develop legislation to regulate fishing • furniture • Heavy penalties for flouting the legislation • medicinal purposes (any two) (2) • Scientific research to inform legislation 3.1.4 • Loss of habitat results in death of organisms/ • Minimal or no fishing during breeding season/limited extinction of species/migration of species fishing season • The balance of gases/carbon dioxide/oxygen • Education and awareness of endangered species will be disturbed because of the loss of plants • Encourage mariculture/sea farming for photosynthesis • Discouraging illegal market by government selling it • Disturb food chains/species migrate/dying out at lower price • Habitat degradation which will result in • Stricter monitoring (2) increased soil erosion reduces fertility [18] of soil (any 2 × 2) (4) 3.3 3.1.5 • Introduce legislation to prevent the removing of trees 3.3.1 Semi-desert (1) • Impose heavy fines/penalties to discourage repeated 3.3.2 Any two of: acts of deforestation • indigestion • Educate people about the negative effects of the • minor infections deforestation/ about the importance of trees • obesity (2) • Research new technologies to find other material 3.3.3 • Indigenous people were the first to use the plant for for building/furniture/fuel (any 3 × 2) (6) suppressing appetite. [16] • Royalty must be paid for their intellectual property. (3) 3.2.1 Annual catches of herring and cod over 8 years [6] 400 3.4 350 3.4.1 • Obtain permission to catch fish/use dam 300 • Conduct training to identify the Tilapia sparrmanii Catches Herring 250 • Decide when to do the investigation 200 • (thousands of tons) Cod Decide on the tags/markers/apparatus to be used 150 • Decide on the method of catching 100 • Determine the sample size/number of repeat samples 50 • Determine the period between the two successive 0 captures 1 2 3 4 5 6 7 8 9 • Decide on how to record the results Year (mark FOUR only) (4) Rubric for the mark allocation of the graph 3.4.2 Number of Tilapia sparrmanii (P) = (15 × 150) Correct type of graph 1 10 Title of graph (both variables) 1 = 225 (3) Correct label for x-axis 1 [7] 3.5 Graphs labelled/key provided 1 3.5.1 a Resource/spatial/niche partitioning for 2 graphs b Intraspecific competition Correct label for y-axis including 1 c Competitive exclusion principle/interspecific unit competition [3] All points joined for graph A 1 All points joined for graph B 1 Total Question 3: [50] Appropriate scale for x-axis 1 Total Section B: [100] TOTAL: [150] Appropriate scale for y-axis 1 Practice Examinations Paper 1: Memo