Life Sciences Grade 11 P1 Eastern Cape November 2016 Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 11 NOVEMBER 2016 LIFE SCIENCES P1 MEMORANDUM MARKS: 150 This memorandum consists of 11 pages.

Downloaded from hlayiso.com 2 LIFE SCIENCES P1 (NOVEMBER 2016) PRINCIPLES RELATED TO MARKING LIFE SCIENCES 2016 1. If more information than marks allocated is given. Stop marking when maximum marks is 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. If 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. 7. 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. Copyright reserved Please turn over

Downloaded from hlayiso.com (NOVEMBER 2016) LIFE SCIENCES P1 3 12. Spelling errors. If recognisable accept provided it does not mean something else in Life Sciences or if it is out of context. 13. If common names given in terminology. Accept provided it was accepted at the provincial memorandum discussion meeting. 14. If only letter is asked for and only name is given (and vice versa). Do not credit. 15. If units are not given in measurements. Candidates will lose marks. Memorandum will allocate marks for units separately. 16. Be sensitive to the sense of an answer, which may be stated in a different way. 17. Caption. All illustrations (diagrams, graphs, tables, etc.) must have a caption. 18. 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. 19. Changes to the memorandum No changes must be made to the marking memoranda without consulting the provincial internal moderator. Copyright reserved Please turn over

Downloaded from hlayiso.com 4 LIFE SCIENCES P1 (NOVEMBER 2016) SECTION A QUESTION 1 1.1 1.1.1 D  1.1.2 D  1.1.3 A  1.1.4 A  1.1.5 A  1.1.6 D  1.1.7 C  1.1.8 A  1.1.9 C  1.10 C  (10 x 2) (20) 1.2 1.2.1 Carrying capacity  1.2.2 Chloroplasts  1.2.3 Culling  1.2.4 Intraspecific competition 1.2.5 Nephron 1.2.6 Egestion/Defaecation  (6 x 1) (6) 1.3 1.3.1 B only  1.3.2 B only  1.3.3 A only  1.3.4 Both A and B  1.3.5 A only  1.3.6 A only  1.3.7 A only  (7 x 2) (14) Copyright reserved Please turn over

Downloaded from hlayiso.com (NOVEMBER 2016) LIFE SCIENCES P1 5 1.4 1.4.1 To demonstrate that light energy  is necessary for photosynthesis.  (2) 1.4.2 The presence/absence of starch  (1) 1.4.3 (Dilute) iodine solution  (1) 1.4.4 (a) No colour change / remain reddish brown  (1) (b) Turns blue-black  (1) 1.4.5 (a) Carbohydrases  (1) (b) Salivary glands  (1) 1.4.6 (a) Oxygen / O2 (1) (b) Oxygen  / O2 (1) TOTAL SECTION A: 50 Copyright reserved Please turn over

Downloaded from hlayiso.com 6 LIFE SCIENCES P1 (NOVEMBER 2016) SECTION B QUESTION 2 2.1 2.1.1 Graph C  (1) 2.1.2 Due to a lower carbon dioxide concentration.  (1) 2.1.3 Temperature  (1) 2.1.4 The graph will show a steady increase in the rate up to 40 ºC  and a further increase in temperature will let it fall dramatically.  (2) 2.1.5 - At higher temperatures, the enzymes become completely denatured / functionless. - When the temperature is increased to 40 ºC, the temperature is optimum for maximum photosynthesis.  (Max. 1) (1) 2.2 2.2.1 (a) Waterplants are structurally adapted to perform photosynthesis under water.  (1) (b) Addition of small amounts of sodium bicarbonate increases the concentration CO2 to bring about a steady rate of photosynthesis. (1) 2.2.2 By counting the number of bubbles released in a minute (unit time)  (1) 2.2.3 - As the intensity of light increases  - the rate of photosynthesis increases proportionately up to a certain point.  - A further increase in light intensity  - will cause no further increase in the rate of photosynthesis.  (Any 3 x 1) (3) 2.2.4 - When the light intensity increases  - the temperature increases proportionately  which - limits the performance of various enzymes  and - hence limit the rate of photosynthesis.  (4) 2.3 2.3.1 3 – Lacteal/ Lymph fluid  Absorption and transport of fatty acids and glycerol.  (2) 2.3.2 Part Labelled 1  (1) 2.3.3 Diffusion/Active transport  (1) Copyright reserved Please turn over

Downloaded from hlayiso.com (NOVEMBER 2016) LIFE SCIENCES P1 7 2.3.4 - It is only one cell thick / thin  so the nutrients can pass through quickly and easily.  - It is richly supplied with mitochondria  - to supply energy for the active transport of many nutrients.  - It also secretes mucus  - that serves as a carrier-fluid for nutrients  - Moist membrane  - to enhance the diffusion of nutrients.  - It has microvilli  - that further increases the surface area for absorption.  (Any 3 x 2) (6) 2.4 2.4.1 It is the cellular imbalance between the supply of nutrients and energy  and the body’s demand for them to ensure growth, maintenance, and specific functions.  (2) 2.4.2 Kwashiorkor  (1) 2.4.3 - Gastric glands in the stomach  - secretes gastric juices which  - contains the enzyme proteases.  - The enzyme proteases hydrolyse/digest  - proteins into polypeptides/peptones  - and eventually into amino acids.  - Protease only function best in an acidic medium.  (5) 2.5 - A large surface area  for maximum exchange of gases  - Thin and permeable  for a rapid and easy diffusion process  - Moist surface  so that gases can dissolve to form a solution  - Must be well-ventilated  to bring fresh air to the exchange surface  - Well-protected  against mechanical damage and drying out.  (Any 3 x 2) (6) [40] Copyright reserved Please turn over

Downloaded from hlayiso.com 8 LIFE SCIENCES P1 (NOVEMBER 2016) QUESTION 3 3.1 3.1.1 A – trachea  B – bronchi  (2) 3.1.2 - The volume in the bell jar increases  which will cause the - pressure in the bell jar to decrease  and the elastic balloons - will expand  increasing their volume and reducing the - pressure within them.  The pressure in the balloons are less - than the atmospheric pressure  therefore air will flow in - through the Y-tube  which will equalise the pressure.  (Any 3 x 1) (3) 3.1.3 The sides of the model are immovable  but in the human chest the rib cage can move upwards and outwards.  (2) 3.2 3.2.1 A – renal vein  B – ureter  C – Inferior vena cava  (3) 3.2.2 The kidney has the important function in the removal of nitrogenous wastes/excess salts from the blood.  (1) 3.2.3 No* (compulsory mark) - If the person suffers from diabetes, there would be a certain - percentage of glucose in the content of structure B.  - A diabetes sufferer will have an abnormal glucose content in the blood  - because his insulin secretion is abnormal.  - Therefore glucose is not converted to glycogen  - hence the glucose is excreted through urine.  (1 compulsory mark + Any 3 x 1) (4) 3.2.4 Glucose,  amino acids and proteins as they get reabsorbed into the blood and do not end up in B to be excreted.  (4) 3.3 3.3.1 - Must all be of the same species  - live in a define area  - and be able to interbreed easily.  (3) 3.3.2 Predator – prey  / predation (1) 3.3.3 64 000 – 66 000 (1) 3.3.4 The lynx population increased*  - on the graph the rabbit population increased. - this result in more food for the lynx  - allowing them to survive and their birth rate to rise.  (1 Compulsory mark + Any 1 x 1) (2) Copyright reserved Please turn over

Downloaded from hlayiso.com (NOVEMBER 2016) LIFE SCIENCES P1 9 3.4 (a) Mutualism is the symbiotic relationship between two organisms of different species where both the individuals derive mutual (nutritional) benefit.  (2) (b) Commensalism is the symbiotic relationship between two organisms in which one organism benefits  while the other neither benefits, nor is it harmed.  (2) 3.5 3.5.1 A – Lag/establishment phase  B – Accelerating/exponential growth phase / geometric growth phase D – Equilibrium/stationary phase (3) 3.5.2 B (1) 3.5.3 - As the size of the population reaches closer to the carrying capacity  - the competition for scarce resources increases  - as a result of environmental resistance  (e.g. shortage food, oxygen, space etc.) - causing an unfavourable condition for rapid reproduction.  (Any 2 x 1) (2) 3.5.4 - The size of human population has nearly reached the carrying capacity of planet earth - resulting severe competition for scarce resources  and - unprecedented exploitation of natural resources  - leading to rapid pollution of air, water and land  - causing further decrease of carrying capacity  - causing increased competition  - and eventually will lead to the *extinction  of mankind. (*Compulsory point) (1 compulsory point + Any 1 x 1) (2) 3.6 - Pioneer species stage  - Intermediate species stage  - Climax community  (Mark only the first two.) (Any 2 x 1) (2) [40] TOTAL SECTION B: 80 Copyright reserved Please turn over

Downloaded from hlayiso.com 10 LIFE SCIENCES P1 (NOVEMBER 2016) SECTION C QUESTION 4 *Process of Glycolysis  - Occurs in the cytoplasm (cytosol)  - it involves phosphorylation  (i.e., addition of energy from ATP) - of energy-rich glucose molecule  - The activated glucose molecule is then broken down into two molecules pyruvic acid.  - Energised hydrogen atoms  releases energy in the process. - This energy is used to form ATP.  - Each step in the process is catalysed by a highly specific enzyme. - No oxygen is required. (*Compulsory mark 1 + 3) (4) *Krebs’ cycle  - Occurs only if oxygen is present.  - Pyruvic acid produced during glycolysis - enters the mitochondria  - where it is used in a cycle series of reactions. - The energised hydrogen atoms - and CO2are released during these reactions. - co-enzymes  transfer the hydrogen atoms. (*Compulsory mark 1 + 3) (4) *Oxidative phosphorylation  / Terminal oxidation / hydrogen transfer system - Occurs in the mitochondria.  - The energised hydrogen atoms (from glycolysis and Kreb’s cycle) are transferred  from one co-enzyme carrier to another. - At each transfer, little energy is given off from the energised hydrogen - until gradually all the energy is drained  from the hydrogen atoms. - This energy is used to combine with ADP + P to form ATP.  - Finally the hydrogen combines with oxygen  - to form water  - The majority of ATP molecules are producing during this stage. (*Compulsory mark 1 + 3) (4) Homeostatic control of CO2 - Receptor cells in the carotid artery in the neck are stimulated  - to send impulses to the medulla oblongata  in the brain. - The medulla oblongata stimulates breathing muscles  (intercostal muscles and diaphragm) - and heart.  - Breathing muscles contract more actively  - increasing the rate and depth of breathing.  - The heart beats faster  - and more CO2 is taken to and exhaled from the lungs.  (Any 5 x 1) (5) Copyright reserved Please turn over

Downloaded from hlayiso.com (NOVEMBER 2016) LIFE SCIENCES P1 11 ASSESSING THE PRESENTATION OF THE ESSAY Criterion Relevance (R) Logical sequence (L) Comprehensive (C) Generally All information Facts are arranged in All aspects required by provided is a logical/ sequential the essay have been relevant to the order. sufficiently addressed. question. In this Only information Events leading up to Learner has scored at essay relevant to the the final production of least: process of ATP and the reduction - Glycolysis (3) respiration and of high levels of CO2 - Krebs’ cycle (3) the homeostatic back to normal level - Terminal oxidation (3) control of CO2 is are provided in the - Homeostatic control of discussed. correct sequence. CO2 (3) (There is no irrelevant information.) MARK 1 1 1 Synthesis (3) TOTAL SECTION C: 20 GRAND TOTAL: 150 Copyright reserved Please turn over