LIFE SCIENCES JUNE EXAMINATION GRADE 11

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1 SPINE ROAD HIGH SCHOOL LIFE SCIENCES DEPARTMENT LIFE SCIENCES JUNE EXAMINATION EXAMINER: T. GABRIELS MODERATOR: Z. SHADE GRADE 11 TIME: 2½ HOURS MARKS: 150 INSTRUCTIONS AND INFORMATION Read the following instructions before answering the questions 1. Answer ALL the questions. 2. Write ALL the answers on the answer sheet provided. 3. Start the answers to EACH question at the top of a new page. 4. Number the answers correctly according to the numbering system used in this question paper. 5. Present your answer according to the instructions of each question. 6. Make ALL drawings in pencil and label them in blue or black ink. 7. Draw diagrams, tables or flow charts only when asked to do so. 8. The diagrams in this question paper are NOT necessarily drawn to scale. 9. Do NOT use graph paper. 10. You must use a non programmable calculator, protractor and compass where necessary. 11. Write neatly and legibly. 1 LIFE SCIENCES JUNE EXAMINATION GRADE 11

2 SECTION A QUESTION Various options are provided as possible answer to the following questions. Choose the correct answer and write only the letter (A to D) next to the question number (1.1.1 to ) on your answer sheet, example A Nutrition in humans includes three process called A. secretion, digestion and absorption B. ingestion, digestion and secretion C. secretion, digestion and excretion D. ingestion, digestion and absorption If all the green plants in the world were destroyed, the atmospheric gas that would increase would be. A. oxygen B. nitrogen C. carbon dioxide D. hydrogen Which of the following shows peristaltic movement? i small intestine ii tongue iii oesophagus iv stomach A. i, and iii B. ii and iii C. iii and iv D. ii and iv The breakdown of glucose in the presence of oxygen in living cells is called A. aerobic respiration B. breathing C. anaerobic respiration D. gaseous exchange 2 LIFE SCIENCES JUNE EXAMINATION GRADE 11

3 1.1.5 Which of the following is responsible for an increase in the concentration of carbon dioxide in human blood? A. hydrolysis B. photolysis C. cellular respiration D. low blood pressure The hormone which regulates the concentration sodium ions in the body. A. Aldosterone B. Antidiuretic hormone C. Adrenalin D. Thyroxin The process in the functioning of the kidney that occurs in the Malpighian body. A. tubular excretion B. glomerular filtration C. tubular reabsorption D. tubular secretion Which of the following is the correct sequence that occurs during kidney functioning? A. pressure filtration excretion re absorption B. re absorption pressure filtration excretion C. excretion pressure filtration re absorption D. pressure filtration re absorption excretion The resource partioning observed in an ecosytem effectively reduces A. the ability of closely related species to interbreed B. competition between closely related species by reducing overlap of ecological niches. C. predatory insinct of related species D. the wastage of food resources 3 LIFE SCIENCES JUNE EXAMINATION GRADE 11

4 Which of the following is a density dependent factor? A. drought B. temperature C. predation D. fire [10 X 2 = 20] 1.2 Give the correct Biological term for each of the following descriptions. Write only the term next to the question number (1.2.1 to ) on your ANSWER SHEET The protective membrane surrounding the lungs The process of filtering the accumulated waste products of the metabolism from the blood of a patient of whose kidneys are not functioning properly The one way movement of the organisms into an area where they become established The type of competition that takes place between individuals of the same species The specific role each species plays in a community Small flap that closes the opening to the trachea during swallowing The organelle concerned with the production of ATP molecules during cellular respiration The structure in the leaf through which gaseous exchange with the environment takes place The part of the lung where gaseous exchange takes place An organic acid that accumulates in the muscle fibres of humans when the supply of oxygen is insufficient. [10 X 1 = 10] 4 LIFE SCIENCES JUNE EXAMINATION GRADE 11

5 1.3 Indicate whether each of the statements in COLUMN I applies to A only, B ONLY, BOTH A and B or NONE of the items in COLUMN II. Write A only, B only, BOTH A and B or NONE next to the question number (1.3.1 to ) COLUMN I The inherent ability of a population to increase in size The part of the air passage in humans that contain c shape cartilage rings The type of epithelium that forms the walls the alveolus The part of the brain that assists with homeostatic control of breathing An example of social organisation that increases the chances of survival COLUMN II A natality B mortality A bronchiole B bronchus A endothelium B squamous epithelium A medulla oblongata B hypothalamus A division of labour in bees B a herd of zebras Has a high concentration of carbon dioxide A pulmonary artery B pulmonary vein The tube that transports urine to the exterior A ureter B urethra The gland in the body that has both an endocrine and exocrine function A liver B pancreas The renal tubes of the kidney that act a sodium pump to maintain sodium level in the medulla A duct of Bellini B loop of henle Process of glycolysis A stroma B granum [10 X 2 = 20] SECTION A: 50 5 LIFE SCIENCES JUNE EXAMINATION GRADE 11

6 SECTION B QUESTION Study the diagram below of the chloroplast in which photosynthesis takes place and answer the questions that follow. A C 1 B D Name the raw materials A and B respectively. (2) Explain why part labelled 1 and 2 assists with the process of photosynthesis. (2) What is the name of the gas C.? (1) Describe how the gas mentioned in Question is formed in the chloroplast. (6) [11] 6 LIFE SCIENCES JUNE EXAMINATION GRADE 11

7 2.2 The diagram below represents a set of apparatus used in an investigation. Study the diagrams and questions based on it. Bell jar Destarched potted plant Plastic bag Sodium DIAGRAM 1 hydroxide solution DIAGRAM 2 Destarched potted plant Sodium bicarbonate solution State a possible hypothesis for this investigation. (2) State the dependent variable for this investigation. (1) What is the purpose of having two sets of apparatus, namely diagram 1 and 2? (2) Explain how the plants in diagram 1 and 2 were destarched. (1) As a precaution plastic paper is placed on the soil. Explain why it important to seal the soil with plastic. (2) Name ONE environmental factor that must remain constant in this investigation. (1) What is the reason for using sodium bicarbonate solution? (2) Explain the possible results for plant in the investigation after testing for starch. (2) [13] 7 LIFE SCIENCES JUNE EXAMINATION GRADE 11

8 2.3 The diagram below represents cellular respiration in a plant cell. Study the diagram and answer the questions. Y Z Identify the phases 2 and 3 respectively. (2) Name the substance labelled X and Z respectively. (2) Identify the products 1 and 3 formed. (2) Explain the process that would happen to compound Y if no oxygen is present. (5) [11] 8 LIFE SCIENCES JUNE EXAMINATION GRADE 11

2.4 Study the diagrams below and answer the questions that follow. DIAGRAM 1 DIAGRAM 2 QUESTION 2: 40 thoracic cavity lungs 2.4.1 Which diagram (1 or 2) illustrates the process of exhalation? (1) 2.4.2 Name the TWO muscles that are involved in the breathing process.

9 2.4 Study the diagrams below and answer the questions that follow. DIAGRAM 1 DIAGRAM 2 QUESTION 2: 40 thoracic cavity lungs Which diagram (1 or 2) illustrates the process of exhalation? (1) Name the TWO muscles that are involved in the breathing process. (2) Describe the relationship between the pressure and volume in diagram 2. (2) [5] QUESTION 2:40 9 LIFE SCIENCES JUNE EXAMINATION GRADE 11

10 QUESTION Read the passage below and answer the questions that follow. Too hungry, too destructive, too many: South Africa to begin elephant cull An elephant herd at Kruger National Park has elephants, more than is sustainable, according to park officials. The South African government decided to lift a suspension on the culling of the native elephant to cope with its booming population. Ecologists say the animals' huge appetites and fondness for "habitat re-engineering" - reducing forests to flatland by uprooting trees and trampling plants as they feed and roam - threaten the biodiversity in the Kruger National Park. But some conservationists argue the environmental impact is less severe than is being claimed, while animal rights campaigners, however killing some of them may disrupt the complex social relationships amongst animals and this is likely to cause a great deal of suffering to the surviving elephants. A conservation director at WWF in South Africa said that the country's rapid elephant population growth of 6% - mainly due to the absence of natural predators of mature animals - was unsustainable. If unchecked, wildlife officials say the elephant count will top by Adapted from The Guardian (26 February 2008) State ONE reason, from the text that is regarded as the contributor to the rapid increase of elephant population in the Kruger National Park. (1) Describe how the increase of the elephant population affects the environment. (2) State TWO reasons derived from the text for the culling of elephants. (2) Besides culling, suggest TWO other methods that could be used to control elephant numbers. (2) Suggest TWO reasons against the culling of elephants. (2) [9] 10 LIFE SCIENCES JUNE EXAMINATION GRADE 11

3.2 The table below represents a certain kind of ecological interaction between two wild animals in a game reserve. Study the table of data and answer the questions that follow.

11 3.2 The table below represents a certain kind of ecological interaction between two wild animals in a game reserve. Study the table of data and answer the questions that follow. YEARS HARE POPULATION LYNX POPULATION Draw a line graph to show the relationship between the Hare and Lynx population. On the same set of axis. (7) From the graph, identify the growth phase representing the Lynx population between 1975 and (1) Provide any TWO reasons for the shape of the graph mentioned in Question (2) Briefly explain the interaction between the Hare and Lynx population. (3) Calculate the percentage decrease of the Hare population between Show ALL your calculations. (3) [16] 3.3 Study the diagram below and answer the questions that follow. G Name the organ represented in the diagram. (1) Give TWO functions of the organ named in Question (2) 11 LIFE SCIENCES JUNE EXAMINATION GRADE 11

3.3.3 Identify the region C and part B. (2) 3.3.4 Give the function of each of the following parts: (a) E (1) (b) G (1) 3.3.5 Explain how the functioning of the above diagram will be affected if part F is blocked by large kidney stone.

Organism A Organism B Organism C 3.4.1 Identify the respiratory organ of organism C. (1) 3.4.2 List THREE important factors that these respiratory organs in the above diagrams have in common for them to be an efficient gaseous exchange surface.

12 3.3.3 Identify the region C and part B. (2) Give the function of each of the following parts: (a) E (1) (b) G (1) Explain how the functioning of the above diagram will be affected if part F is blocked by large kidney stone. (2) [9] 3.4 The three organisms shown below all have a different mechanism by which they get oxygen from the surrounding environment. Study the diagrams and answer the questions that follow. Organism A Organism B Organism C Identify the respiratory organ of organism C. (1) List THREE important factors that these respiratory organs in the above diagrams have in common for them to be an efficient gaseous exchange surface. (3) Explain why the respiratory organ used by organism A would not be a suitable respiratory organ for organism B. (2) [6] QUESTION 3:40 TOTAL SECTION B: LIFE SCIENCES JUNE EXAMINATION GRADE 11

13 SECTION C QUESTION Breakfast is the most important meal of the day. It provides you with the energy and it also helps to maintains your blood glucose level throughout the day. Explain how the human body regulates the blood glucose levels after a breakfast of maize meal porridge. Content: 17 marks Synthesis (Relevance, the logical sequence and comprehension of facts):3 marks NOTE: No marks will be awarded for answers in the form of tables, flow charts or diagrams. TOTAL SECTION C: 20 GRAND TOTAL: LIFE SCIENCES JUNE EXAMINATION GRADE 11

14 SPINE ROAD HIGH SCHOOL LIFE SCIENCES DEPARTMENT LIFE SCIENCES JUNE EXAMINATION 2017 MEMORANDUM EXAMINER: T. GABRIELS MODERATOR: Z. SHADE GRADE 11 TIME: 2½ HOURS MARKS: 150 INSTRUCTIONS AND INFORMATION Read the following instructions before answering the questions 1. Answer ALL the questions. 2. Write ALL the answers on the answer sheet provided. 3. Start the answers to EACH question at the top of a new page. 4. Number the answers correctly according to the numbering system used in this question paper. 5. Present your answer according to the instructions of each question. 6. Make ALL drawings in pencil and label them in blue or black ink. 7. Draw diagrams, tables or flow charts only when asked to do so. 8. The diagrams in this question paper are NOT necessarily drawn to scale. 9. Do NOT use graph paper. 10. You must use a non programmable calculator, protractor and compass where necessary. 14 LIFE SCIENCES JUNE EXAMINATION GRADE 11

15 11. Write neatly and legibly. SECTION A QUESTION D C A A C A B D B C [10 X 2 = 20] Pleura / pleural membrane Dialysis Immigration Intra specific competition Ecological niche / niche Epiglottis Mitochondria Stomata Alveoli Lactic acid [10 X 1 = 10] A ONLY NONE B ONLY A ONLY BOTH A AND B A ONLY B ONLY B ONLY B ONLY NONE [10 X 2 = 20] QUESTION 1: LIFE SCIENCES JUNE EXAMINATION GRADE 11

16 SECTION B QUESTION A CO 2 / H 2 O B H 2 O / CO 2 (2) ribosome produces enzymes which control the process of the light independent phase of photosynthesis. 2 Grana traps light which is important for the light dependent phase of photosynthesis. (2) O 2 (1) Light dependent phase { Mark only the first 6 facts} It takes place in the grana of the chloroplast. Chlorphyll molecules traps/ absorbs radiant energy. Radiant energy is converted into chemical energy. Chemical energy is used to form ATP and to split the water molecule by the process of photolysis into hydrogen and Oxygen. (6) [11] In the presence of CO 2 plants will produce starch during photosynthesis. OR In the absence of CO 2 plants will not be able to produce starch during photosynthesis. OR CO 2 has no effect on the rate of photosynthesis. (2) Amount of starch produced. (1) One set serves as a control to compare the results of the experiment. (2) It was placed in a dark place for 48hours to destarch the leaves. (1) Micro organism in the soil when decomposing organic matter release CO 2, which will make carbon dioxide available for the set up in diagram 1. [Mark first two only] (2) Light intensity, temperature and water {Any 1} (1) To increase CO 2 available for photosynthesis (2) 16 LIFE SCIENCES JUNE EXAMINATION GRADE 11

17 2.2.8 When tested for the presence of starch, the leaves of diagram 1 and will be negative while those of diagram 2 will be positive. (2) [13] Phase 2 Kreb cycle 3 Oxidative phosphorylation (2) X Glucose Z Oxygen (2) Carbon dioxide 3 Water (2) Process of Alcoholic Fermentation : Only glycolysis occurs Glucose is broken down Pyruvic acid is formed Small amounts of energy is released Pyruvic acid is broken down further Carbon dioxide is released and alcohol is formed. [Any 5] (5) [11] Diagram 2 (1) External intercostal muscle and diaphragm (2) The decrease of the volume of the thoracic cavity results in the lungs will cause an increase in the pressure lungs. OR The increase of the volume of the thoracic cavity results in the lungs will cause a decrease in the pressure lungs. OR Pressure is indirectly proportional to the volume. (2) [5] QUESTION 2:40 QUESTION They have no natural predator for mature animals. (1) They reduce forest to flatland by uprooting and trampling on plants as they feed threatening the biodiversity (ANY TWO) (2) Their population size is increasing unsustainably With their huge appetites they are a threat to biodiversity (2) Contraception Translocation / Trans frontier parks (ANY TWO) (2) 17 LIFE SCIENCES JUNE EXAMINATION GRADE 11

18 3.1.5 It is inhumane / against God It may disrupt the social structure of the elephants leading to a great suffering by the surviving ones (MARK first TWO) (2) [9] (7) Lag phase (1) 18 LIFE SCIENCES JUNE EXAMINATION GRADE 11

19 3.2.3 Slow growth Predators are still getting use to the environment. Seeking mating partners Predators have not reached sexual maturity. (Any TWO) (2) By feeding on the Hare population, the lynx population reduces the numbers of their prey. - As the number of Hare population drops - More competition among lynx population occurs - Thus resulting in a decrease in the predator numbers. - An increase in the Hare population and increase in the lynx population, Finally the predator prey population stabilizes around the carrying capacity resulting in a stable population. (Mark first 3) (3) ( ) X 100 = 150 = 37,5% (3) [16] Kidney (1) Excretion of nitrogenous waste Regulates the salt content in the blood Regulates the water content (osmoregulation) in the blood Regulates the ph of the blood. [ANY TWO] (2) C Medulla B Renal pyramid (2) a) Protects the kidney. (1) b) Transports deoxygenated blood purified from metabolic waste away from the kidney. (1) Urine will not be able to flow from the renal pelvis to the bladder because the ureter is blocked. The urine will be pushed back into the kidney. (2) [9] Gills (1) Large surface area, richly supplied by blood, moist, good ventilation and well protected. {any 3} (3) The surface area to the volume ratio in humans is too small. The skin would not be able to absorb enough oxygen to meet the demands of the body. (2) [6] QUESTION 3: LIFE SCIENCES JUNE EXAMINATION GRADE 11

20 SECTION C SECTION B: 80 QUESTION 4 Maize porridge is rich in carbohydrates. Carbohydrates (starch) is digested into simpler substances such glucose. In the mouth the saliva containing amalyse acts on the maize porridge (starch) which breaks down the starch into glucose. The porridge then undergoes chemical digestion in the stomach. The absorption of glucose takes place in the small intestines by the villi. The glucose is then taken to the liver and assimilation takes place. The absorption of glucose into the blood causes the glucose in the blood to increase The pancreas is then stimulated, which causes the islets of langerhans of the pancreas to secrete insulin. Insulin inhibits the secretion of glucagon, this known as negative feedback Glucagon stimulates the conversion of glycogen into glucose Insulin travels in the blood to the liver In the liver insulin stimulates the conversion of excess glucose into glycogen The glucose concentration in the blood decreases and returns to normal Glycogen is then stored in the liver [ 17 facts] Content: (17) Synthesis: (3) Criterion Relevance (R) Logical sequence (L) Comprehensive (C) Generally All information provided is relevant to the homeostatic control of high blood Contents of breaking down of the porridge. Comprehends the absorption of glucose, lowering blood sugar level to normal glucose levels Mark TOTAL SECTION C: 20 GRAND TOTAL: LIFE SCIENCES JUNE EXAMINATION GRADE 11

GRADE 11 NOVEMBER 2013 LIFE SCIENCES P1

GRADE 11 NOVEMBER 2013 LIFE SCIENCES P1 NTIONL SENIOR ERTIFITE GRE 11 NOVEMER 2013 LIFE SIENES P1 MRKS: 150 TIME: 2½ hours This question paper consists of 14 pages. 2 LIFE SIENES P1 (NOVEMER 2013) INSTRUTIONS N INFORMTION Read the following