Life Sciences Grade 12 Paper 2 NSC June 2013 Memo

Downloaded from hlayiso.com basic education Department: Basic Education REPUBLIC OF SOUTH AFRICA SENIOR CERTIFICATE EXAMINATION BIOLOGY P2 2013 POSSIBLE ANSWERS | STANDARD GRADE | | i J} MARKS: 150 ndum consists of 10 pages. Copyright reserved Please turn over

Downloaded from hlayiso.com Biology/SG/P2 2 DBE/2013 SCE — Memorandum PRINCIPLES RELATED TO MARKING HG & SG BIOLOGY 2013 This document should be attached fo alf memoranda after the question paper has been written and made available to ALL Life Sciences/Biology teachers. 1. If more information than marks allocated is given Stop marking when maximum marks are reached and put a wavy line and ‘max’ in the right-hand margin. 2. If, for example, three reasons are required and five are given “Mark the first three irrespective of whether all or some are correct/incorrect. 3. If whole process is given when only part of it is required Read all and credit relevant part. 4. tf comparisons are asked for and descriptions are given Accept if differences / similarities are clear. 5. If tabulation is required but paragraphs are given Candidates will lose.marks for not tabulating. 6. If diagrams are given with annotations when descriptions are required Candidates will lose marks. Ue If flow charts are given instead of descriptions Candidates will lose marks. 8. If sequence is muddled and links do not make sense Where sequence and links are correct, credit. Where sequence and links are incorrect, do not credit. If sequence and links becomes correct again, resume credit. 9. Non-recognised abbreviations Accept if first defined in answer. If not defined, do not credit the unrecognised abbreviation but credit the rest of answer if correct. 10. Wrong numbering If answer fits into the correct sequence of questions but the wrong number is given, it is acceptable. 11. If language used changes the intended meaning Do not accept. 12. Spelling errors If recognisable ac cept provided it does not mean something else in Biology or if it Bomiition flames given in terminology Accept provi pted at this memo discussion. 9013 -08- 05 2 < C1140 Copyrig) es: oi eo Please turn over FMDWiese External Moderator Unralusi

Downloaded from hlayiso.com Biology/SG/P2 3 DBE/2013 14. 15. 16. 17. 18. 19. 20. 21. SCE - Memorandum If letter only is asked for and name only is given (and vice versa) No credit. If units are not given in measurements Candidates will lose marks. Memorandum will allocate marks for units separately. Be sensitive to the sense of an answer, which may be stated in a different way. Caption All illustrations (diagrams, graphs, tables, etc.) must have a caption. If you have doubts consult the other language memo. If you still have doubts ask the Provincial Internal Moderator to contact the National Internal Moderator or the External Moderator(s). Code-switching of official languages (terms and concepts) A single word or two that appears in any official language other than the learners’ assessment language used to the greatest extent in his/her answers should be credited, if it is correct. A marker that is proficient in the relevant official language should be consulted. This is applicable to all official languages. No changes may be made to the marking memoranda without consulting the Provincial Internal Moderator who in turn will consult with the External Moderator(s). Only memoranda bearing the signatures of the UMALUSI moderators and distributed by the National Department of Education via the Provinces may be used. : Copyright reserved . Please turn over FSM. Wiese External Moderator” Umatusi

Downloaded from hlayiso.com Biology/SG/P2 4 SCE - Memorandum SECTION A QUESTION 1 1.1 111 Cvv 112 Dvv 113 Dvv 114 Cvv 115 BYY 116 Avvw (6x2) = (12) 1.2 1.2.1 Guard cells ¥ 1.2.2 HydathodesY 1.23 Synapsv 1.2.4 Hormone ¥ 41.2.5 Loop of Henle ¥ (5) 13 13.1 Evv 13.2 Gvv a3 ive, 134 Avv 135 FYY (5x2) (49) 1.4 1.4.1 (a) Dust ¥ (b) Nose ¥ (c) SneezingY (d) Reflex action ¥ (4) Copyright reserved Please turn over External Moderator imatus}

Downloaded from hlayiso.com Biology/SG/P2 5 SCE — Memorandum 1.4.2 - The ciliary muscles relaxY - ciliary body moves further away “from the lens - suspensory ligaments become taut ¥ - lens becomes less convex “ - to focus light rays on retina ¥ 1.5 1.5.1 - Increases¥ - More light enters eye v‘to form clear image . (2) 1.5.2 - Decreases¥ - So that blood supply to strategic parts increasesY” a 1.6 1.6.1 100 vcm?v (2) 1.6.2 (400 cm? + 500 cm® + 1500 cm®) v = 2400 vem? v (3) 16.3 400 Vv cm® (2) 1.7 1.7.1 Water loss/ transpiration/ absorption “ (1) 1.7.2 - Make sure the apparatus is air tight” V/Use a rubber stopper - Insert the twig in water vv to prevent plant from dying out before the investigation is completed - Cut the twig under watery’ v to prevent air bubbles from entering the xylem - Use a sharp knife to prevent VY damage of xylem tissue (Mark first answer only) = (2) 1.7.3. - To move water upwards/ from the roots to the leaves/ for photosynthesis Vv OR - Evaporation of water has a cooling ¥ OR - To move mineral salts to the leaves¥ (Mark first answer only) (1) (4) TOTAL SECTION A: 50 Copyright reserved GM. Wiese Please turn over External Moderator mafusi

Downloaded from hlayiso.com | DEPARTMENT GF BASIC : E Biology/SG/P2 6 DUCATION SCE — Memorandum 2013 -06- 05 SECTION B PRIVATE BAG X 110 PRETORIA 0001 QUESTION 2 PUBLIC EXAMINATIONS 2.1 2.1.1. - The water diffused” into the cell mode! “/water was taken up through osmosis (2) 2.1.2 -80%4 (compulsory mark) (1) - because the cell model did not increase in mass VW” - because the cell model did not changevY - according to the table, when the mass of the cell model is 10g, the concentration of water outside the cell model is 80% Vv (this would be the same as the concentration of water inside the cell model) (Any1x2) (2) 2.1.3. - Repeat the investigation several times Vv OR - Use more than one cell model for each concentration of water WY” (any1x2) (2) (7) 2.2 2.2.1 Osmosis / diffusion ¥ (1) 2.2.2 Toolargev (1) 2.2.3 } +. j u v A | A’B 28 B f Av | A a i Bp a TA A container showing distribution of molecules A and B after net movement of these molecules v Marking guidelines: allocate marks for: - Heading ¥ - Showing molecules AY equal v in each compartment / (three A’s) - Quality of drawing (neat and clear) W - Molecules B only on the right hand side “ (5) (7) Copyright reserved Please turn over I M,Wiese External Modesotor matuss

Downloaded from hlayiso.com Biology/SG/P2 7 DBE/2013 SCE —- Memorandum i DERARTMENT OF BASIC i EDUCATION 23 i i 2.3.1 Vacuole ¥ i 2013 -06- 05 (1) i i PRIVATE BAG X 110 aed ead j PRETORIA 0001 () i 2.3.3. plasmolysis ¥ / exosmosis 1_PUBLIC EXAMINATIONS (1) 2.3.4 cell membrane) Vacuole fluid v cell wall v A plasmolysed cell Marking guidelines: The diagram must show that: - The cell membrane has been pulled away from cell wall/ has shrunkY¥” (see diagram) - Caption/neadingY - Any correct label” (4) (7) 2.4 2.4.1 - So that solution A does not mix with solution B Vv// no leakage (2) 2.4.2 - To make sure that there is no sugar solution on the outside of the dialysis tubingv¥ (2) (4) [25] Copyright reserved Gt Wee. a) Please turn over Enero! Moderator Imatust

Biology/SG/P2 & DBE/2013 QUESTION 3 i EDUCATION 3.1 i | 2013 -06- 05 3.1.1 A-Epidermis ¥ { ST Trepe B — Dermis V/ adipose tissue / fat layer \ Beate Cea gland ““SOGLIc EXAMINATIONS 3.1.2 Secretes sweat Vv sweat released on the surface of the skin’ sweat evaporates V evaporation causes Cooling” of the skin 3.1.3. - Forms sweat W - that evaporates” - to cool down the body ” (Any 2) 3.1.4 Hairv OR Fat tissue V 3.1.5 Dilated v 3.1.6 - More blood is brought to the skin v - thus more heat brought to the skin W - from where heat is lost to the atmosphere ” - This reduces the body temperature further “ (Any 3) 3.2 - Marine mammals have a thick layer of blubber v‘that insulate their bodies 3.3 3.3.1 Thyroid gland¥ 3.3.2 Straddling the trachea, Y below the larynx W 3.3.3. - Controls body growth Vv - Control metabolic rate / Increases metabolism VY - Increases blood glucose VW - Development of the nervous system / brain vv” (Any 2 x 2) 3.3.4 lodine is needed to make thyroxin Vv“ Copyright reserved ‘7° Please turn over dl SM. Wiese Downloaded from hlayiso.com SCE — Memorandum DEPERTMENT OF BASIC Externol Moderator Umolusi 3) (4) (2) (1) (1) (3) (14) (2) (1) (2) (4) (2) (25)

Downloaded from hlayiso.com Biology/SG/P2 9 | ___ ERUCATIOND as 2640- SCE -— Memorandum 2013 -06- 05 QUESTION 4 PRIVATE BAG X 110 41 PRETORIA 0004 , PUBLIC EXAMINATIONS 4.1.1 D: Renal vein ¥ E: (Renal) pelvis Vv F: (Renal) calyx ¥ 4.1.2 Bcontains the glomeruli” “/more capillariesv “/Malpighian bodies VW” C contains no glomeruli” / Malpighian bodies” “/ fewer capillariesY “ 4.1.3 A- (Renal) capsule “ Protects vv inner parts of kidney 4.1.4 To keep kidney in place~ / protects kidney against injury /shock absorber/ insulates the kidney 4.2 4.2.1 ADHY 4.2.2 Hypothalamus” / Hypophysis / Pituitary gland 4.2.3 ADH causes water reabsorption v (at the kidneys); Which increases blood volume / more water in the blood; ¥ Greater blood volume contained within closed vessels; Increased blood volume returning to heart ¥ heart has to work harder “ (Any 2) 4.3 4.3.1 (18,0 + 1,5) ¥ = 19,5 v gv 4.3.2 - No need to cool down the body on a cold dayY - hence less sweat formed¥ - more blood is diverted to the internal organs V - and excess water lost as urinew (any 3x1) 4.3.3. - Waste substances are continuously formed” - and must be transported in dissolved state” 43.4 Hot¥ 4.3.5 - Person sweats more on a hot day¥ - to cool down the bodyY - hence more water lost as sweat” - more ADH ~secreted - more water is reabsorbed “ - and less water in the urine ¥ (Any 3) Copyright reserved : Please turn over External Moderator malusi (2) (3) (1) (9) (1) (1) (2) (4) (3) (3) (2) (1) (3) (12) (25)

Downloaded from hlayiso.com DEPARTMENT OF BABIG,5 Biology/SG/P2 10 SCE - Memorandum EDUCATION QUESTION 5 2013 -06- 05 RIVATE BAG X 110 5.1 ° PRETORIA 0001 §.1.1 122-124V cmv PUBLIC EXAMINATIONS 2) §.1.2 12-13.5” yearY (2) 5.1.3 55-58¥ cmv (2) 5.1.4 Increased heightv v / larger / get bigger / taller / weight / mass / number of cells (2) 5.1.5 Number of cells “~/ mass / weight / bigger/size (2) (10) 5.2 5.2.1 - 20 ¥cm (1) 5.2.2 - Between 10 and 20 years of age, the reaction time of males and females is almost the same Vv - The reaction time of older people is longer than that of younger people” - Reaction time of males between 30 and 50 years is faster than that of females of the same ageY” (Any 1 x 2) (2) §.2.3 -20~ years. (1) 5.2.4 - Test more males and females in each age group.v¥W” (2) 5.2.5 -Eyev (1) (7) 5.3 5.3.1. - Conjunctiva. ~ (1) 5.32 (a) -EY (1) (b) -Av (1) (c) -BY (1) dd) -FY (1) (e) -Dv (1) 5.3.3 G-Retinav - receives light stimulusv/ changes stimulus into an impulse. (2) (8) (25) TOTAL SECTION B: 100 GRAND TOTAL: 150 Copyright te] Wau. as ee SA, Wiese Eternal Moderatoy / i ans pol Fos ol.