SPINE ROAD HIGH SCHOOL

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1 SPINE ROAD HIGH SCHOOL LIFE SCIENCES DEPARTMENT LIFE SCIENCES SEPTEMBER 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 answers on the answer sheet provided 3. Start the answers to EACH questions at the top of a new page 4. Number the answers correctly according to the number system used in this question paper. 5. Present your answer according to the instructions of each question 6. Make ALL drawings in pencil and labels in blue or black ink 7. Draw diagrams, tables or flow charts only when asked to do so 8. The diagrams in this question are NOT necessarily drawn to scale 9. DO NOT use graph paper 10. You must use non programmable calculator, protractor and compass where necessary 11. Write neatly and legibly. 1 LIFE SCIENCES _ SEPTEMBER EXAMINATION

2 SECTION A QUESTION Various options are provided as possible answers 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 1.1.8) in your ANSWER BOOK, for example D A virus consists of A. RNA, DNA and a protein coat B. proteins, cell membrane and RNA C. RNA or DNA and a protein coat D. RNA or DNA and a cell membrane During the dominant stage of their life cycle, ferns are visible as A. haploid gametophyte B. haploid sporophyte C. diploid gametophyte D. diploid sporophyte The use of antibiotics is an effective treatment for A. bacterial and viral infections B. bacterial infections only C. viral infections only D. neither bacterial nor viral infections Which of the following is NOT TRUE of genetically modified crops? A. increase in genetic diversity B. reduced reliance on pesticides C. withstand long periods of droughts D. increasing crop yield 2 LIFE SCIENCES _ SEPTEMBER EXAMINATION

3 1.1.5 Which of the following is present in Bryophytes? A. seeds B. xylem C. spores D. flowers Which ONE of the following represents a positive human impact in the environment? A. pollution B. conservation C. environment degradation D. population explosion Greenhouse gases that traps the most heat and leads to global warming A. methane B. water vapour C. nitrous oxide D. carbon dioxide In which of the following plant groups do male gametes depend on water to swim towards the ovum? A. pteridophytes and gymnosperm B. pteridophytes and angiosperm C. bryophytes and gymnosperm D. bryophytes and pteridophytes (8 X 2) [16] 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 ) in your ANSWER BOOK A term used to describe organism that cause disease Process by which bacteria break organic matter into simple nutrients which are then returned to the soil. 3 LIFE SCIENCES _ SEPTEMBER EXAMINATION

4 1.2.3 The symbiotic relationship between two organisms where both benefit A single crop species that is planted on the same piece of land for consecutive years The mass of hyphae constitutes the vegetative body of a fungus The planting of trees for commercial purposes The cells that fuse together to form a zygote The female reproductive organs of mosses A measure of the total greenhouse gas emissions by an individual, company or a country per year Root like structure in moss plants. 4 LIFE SCIENCES _ SEPTEMBER EXAMINATION (10 X 1) [10] 1.3 Indicate whether each of the descriptions 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 1.3.7) in your ANSWER BOOK. COLUMN I COLUMN II Carbon footprint can be reduced by A: Recycling B: Reusing Site constructed to dispose of waste A: Reservoir B: Land Fill Factors decreasing water availability A: Alien plants B: Indigenous plants Yeast is a unicellular fungus used in A: Cheese traditional technology to make B: Yogurt Plants without true roots, stems and A: Angiosperm leaves B: Thallus Dominant generation in A: Sporophyte Pteridophytes B: Gametophyte When biological productivity is A: Desertification reduced and conditions become desert like B: Deforestation (7 X 2) [14]

5 1.4 Chloroflurocarbon (CFC) has unfortunately caused considerable damage to the ozone layer, resulting in the formation of big holes. Study the graph below showing the extent of the damage in the Antarctic ozone layer and answer the questions that follow During which year was the hole in Antarctic area the: (a) Largest? (1) (b) Smallest? (1) What was the area of the hole (millions km 2 ) in the years: (a) 2000 (1) (b) 2005 (1) [4] 5 LIFE SCIENCES _ SEPTEMBER EXAMINATION

6 1.5 The diagram below shows a part of the fungi s life cycle. Study the diagram below and answer the questions that follow. D Identify the parts that have the following functions: (a) Produces spores. (1) (b) Anchors the fungus on the substrate. (1) Identify the parts that represent the sporangiophore and stolon. (2) Give TWO examples of fungal diseases that affect humans. (2) [6] TOTAL QUESTION 1: 50 TOTAL SECTION A: 50 6 LIFE SCIENCES _ SEPTEMBER EXAMINATION

7 SECTION B QUESTION The diagram below is that of a bacterial cell. Study the diagram and Answer the questions based on it. Plasmid Provide the labels for parts numbered 1 and 7 respectively. (2) State the functions of the part labelled 4. (1) Explain how the Plasmid in a bacterium cell can be used in the manufacturing process to make insulin for diabetics. (5) [8] 7 LIFE SCIENCES _ SEPTEMBER EXAMINATION

8 2.2 A group of grade 11 Life Sciences learners at Spine Road High carried out an experiment to find out what factors help mould to grow on bread. They took 4 slices of white bread and put different substances on each slice of bread as follows: Slice 1: Was left dry Slice 2: 20 ml of tap water Slice 3: 20 ml of lemon juice Slice 4: 20 ml sugar water Each slice of bread was placed in a Ziploc bag and kept in a dark cupboard at a temperature of about 25 o C for two weeks. They observed the growth of mould on the four slices of bread and worked out he percentage area of the bread covered by mould. The results are shown in the graph below State a hypothesis for this investigation. (2) Name the independent variable. (1) Explain why mould did not grow well on bread sprinkled with lemon juice? (2) Why was dry bread included in the experiment? (2) 8 LIFE SCIENCES _ SEPTEMBER EXAMINATION

9 2.2.5 Use the information in the graph and represent the data in a table. (5) Describe the ideal conditions to promote the development of mould on the bread. (2) [14] 2.3 Read the following extract and answer the questions that follows To which group of micro organism does the malaria parasite belong? (1) State any TWO ways to avoid contracting malaria. (2) Describe how the malaria parasite is passed from one human to another. (2) Explain how an increase in the number of malaria infections would affect the South African economy. (2) Give ONE reason why a person with malaria cannot be treated by using an antibiotic. (2) [9] 9 LIFE SCIENCES _ SEPTEMBER EXAMINATION

10 2.4 Study the diagram below showing the life cycle of a fern plant and answer the questions that follow. A Figure 2 B C Figure 1 D E G F Figure Which generation is represented by figure 3? (1) Explain why the generation represented in figure 3 has a short lifespan. (2) Give the NAME of the label that represents the female sex organs in figure 3. (1) Which of the figures above form part of the dominant generation in a fern? (2) What is the function of the part labelled C in figure 2? (1) Briefly explain why water is necessary for fertilisation to occur. (2) [9] TOTAL QUESTION 2: 40 QUESTION 3 10 LIFE SCIENCES _ SEPTEMBER EXAMINATION

11 3.1 The graph below shows a comparison of the percentage of water stored in dams in each province in South Africa between October 2014 and October Answer the questions below on the data shown in the graph Comment on the comparison of water stored in the country s dams between October 2014 and October 2015 in general. (2) Which province experienced the sharpest decrease in water storage over the year? (1) Account for this notable decrease in water storage in the Province mentioned in QUESTION (2) Briefly discuss TWO ways in which the construction of a dam can be disadvantageous. (4) [9] 3.2 Despite a great increase in the demand for food, only 7% more land is now used for farming. One of the reasons for this is increased productivity, that is a higher yield per hectare, 11 LIFE SCIENCES _ SEPTEMBER EXAMINATION

12 due to GMOs as well as the use of pesticides and fertilisers. In the last 30 years, people have become more aware of the use of chemicals in farming. Some people are concerned about the effects of these on their health and choose to buy organically grown produce. Farmers who use organic methods produce food do not use chemicals on their crops Give ONE reason for an increase in the demand for food over the years. (1) State ONE way in which the use of each of the following helps increase productivity: (a) Pesticides (1) (b) Fertilisers (1) Explain how the use of pesticides could destroy food chains. (2) Explain why GMOs can be considered to be a threat to food security. (2) Explain how farmers who use organic methods protect their crops if they do not use chemicals. (2) [9] 3.3 The graph below shows South African Rhino poaching statistics using data published by the South African Department of Environmental Affairs (2016). Study the graph and then answer questions which follow. 12 LIFE SCIENCES _ SEPTEMBER EXAMINATION

13 3.3.1 Define the term poaching. (1) Give THREE reasons why animals such as rhino are poached. (3) Calculate the percentage increase in the number of rhino poached between 2013 and Show all your calculations. (3) Suggest THREE ways in which the poaching of rhino can be reduced. (3) [10] 3.4 Deforestation is the large scale removal of trees, which eventually destroys forests. The table below shows statistics related to deforestation in different regions during the last decade. Region Total land area Total forest cover (hectare) Forest cover (%) Africa ,8 0,8 Asia X 0,1 North and Central America ,7 0,1 Oceania and Australia ,3 0,2 Deforestation rate (%) What region had the highest rate of deforestation in the 10 year period? (1) Calculate the percentage forest cover of Asia indicated by X. (2) 13 LIFE SCIENCES _ SEPTEMBER EXAMINATION

14 3.4.3 Explain how deforestation impacts the earth s water table. (3) Give THREE ways to decrease deforestation. (3) Describe THREE negative consequences of deforestation on the natural environment. (3) [12] TOTAL QUESTION 3: 40 TOTAL SECTION B: 80 SECTION C QUESTION Describe how reproduction in Bryophytes takes place and explain how Pteridophytes are more terrestrially adopted than bryophytes. Content: Synthesis (RLC): 17 marks 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 _ SEPTEMBER EXAMINATION

15 SPINE ROAD HIGH SCHOOL LIFE SCIENCES DEPARTMENT LIFE SCIENCES SEPTEMBER EXAMINATION EXAMINER: T. GABRIELS MODERATOR: Z. SHADE GRADE 11 MEMORANDUM TIME: 2½ HOURS MARKS: 150 INSTRUCTIONS AND INFORMATION Read the following instructions before answering the questions 1. Answer ALL the questions 2. Write ALL answers on the answer sheet provided 3. Start the answers to EACH questions at the top of a new page 4. Number the answers correctly according to the number system used in this question paper. 5. Present your answer according to the instructions of each question 6. Make ALL drawings in pencil and labels in blue or black ink 7. Draw diagrams, tables or flow charts only when asked to do so 8. The diagrams in this question are NOT necessarily drawn to scale 9. DO NOT use graph paper 10. You must use non programmable calculator, protractor and compass where necessary 11. Write neatly and legibly. 15 LIFE SCIENCES _ SEPTEMBER EXAMINATION

16 SECTION A QUESTION C A B A C B D D [16] Pathogen Decomposition / nutrition recycling Mutualism Monoculture Mycelium Afforestation Gametes Archegonium Carbon foot print Rhizoid [10] Both A and B B only A only None B only A only A only [14] (a) 2014 (b) 1994 (1) (1) (a) 9 10 (1) (b) (1) [4] 16 LIFE SCIENCES _ SEPTEMBER EXAMINATION

17 1.5.1 (a) A (1) (b) C (1) B and D (2) Thrush, athletes foot or ringworm (any 2) (2) [6] TOTAL SECTION A: 50 QUESTION Ribosome 7 Flagellum (2) Protects the bacterium against dehydration. (1) Using the Plasmid in bacterium cell to manufacture insulin: A plasmid (ring shaped DNA) is removed from the E. coli bacteria Restriction enzymes are used to cut the plasmids A human gene of insulin is inserted into the plasmid The plasmid and human gene of insulin joins to re form a plasmid of recombinant DNA. The recombinant DNA is placed back into the E. coli bacteria. The E.coli bacteria accept the new gene as part of its genetic material. The E.coli bacteria starts to reproduce to produce many insulin producing bacteria The insulin is extracted, purified and sold to treat diabetes. [ Any 5 facts] Sugar water helps mould grow more than other factors on bread. OR Tap water/ lemon juice has the least mould growth than sugar water on bread. OR Factors (tap water/ lemon juice/ sugar water) has no influence on growth of mould on bread (2) (5) [8] Type of nutrients substance on bread (1) 17 LIFE SCIENCES _ SEPTEMBER EXAMINATION

18 2.2.3 Lemon juice is acidic which will hinder the growth of fungi. (2) To act as the control to compare results without the independent variable. (2) Percentage of mould growth using different substances Different substances Percentage of mould on bread Dry white bread 0 Tap water on bread 2,0 Lemon juice on bread 1,0 Sugar water on bread 4,0 1 mark table and 2 marks for filling the data in the table (5) Moist and dark environment (2) [14] Protista (1) Take anti malarial drugs Use insect repellents on exposed skin Sleep under mosquito nets Sleep in long sleeve sleepwear Empty areas of standing water to prevent breeding of mosquitoes [Mark first TWO only] (2) The Anopheles mosquito bites an infected person the parasite is sucked in and develops further in the vector and the mosquito bites another person transferring the parasite (Any TWO) (2) The economy will be negatively affected as the cost for malarial treatment is high / decreased work production (2) Antibiotics can only be used to treat disease caused by bacteria and malaria is transmitted by a protist. (2) [9] 18 LIFE SCIENCES _ SEPTEMBER EXAMINATION

19 2.4.1 Gametophyte generation (1) It disappears after one cycle of gamete formation and fertilisation (2) Archegonia (1) Figure 1 AND figure 2 (2) It stores and produces spores. (1) Sperm cells from the antheridia need water to swim to the egg cells in the archegonia. (2) [9] TOTAL QUESTION 2: 40 QUESTION There has been a decrease in stored water in country s dam between October 2014 and October 2015 OR The Eastern Cape experienced a 2% increase in stored water (2) Western Cape (1) A very dry summer season being followed by a drier than normal winter which usually occurs when this region received rains and its dams fill up (2) People and their livelihoods are affected as they may have to relocate due to a shortage of water. - Natural balance/ flow of the river is upset and reduces biodiversity - Large surface area increase the amount of water lost by evaporation (2X2) (4) [9] 19 LIFE SCIENCES _ SEPTEMBER EXAMINATION

20 3.2.1 There has been a rapid increase in the human population (1) (a) Pesticides kill the pest which destroy the crops (1) (b) Fertilisers increases nutrient content in the soil (1) Secondary consumers such as birds can eat the pests with the poison which can kill the birds there by decreasing the population size of the birds. OR Pest can become extinct and the secondary consumers feeding on would decrease in numbers due to a shortage of food. (2) Loss of Flora and Fauna biodiversity by inbreeding of GMOs Entire species could be wiped out if exposed to disease (2) They make use of biological control to control the pest and make use of natural compost to fertilise the soil (2) [9] Illegal hunting and killing of animals/ illegal removal of plants (1) Meat serves as food - Parts are used for making muti - Rhino horns are used as aphrodisiac - Illegal trade brings in lots of money (ANY 3) (3) (3) (3) Stricter law enforcement - Tracking device inserted in the rhino horns - Treating the horns with a dye - Legal harvesting by authorities (Any THREE) (3) [10] 20 LIFE SCIENCES _ SEPTEMBER EXAMINATION

21 3.4.1 Africa (1) X 100/ = 17,75 or 17,8% (2) There is no plants/ trees to take in the water through their roots excess would not evaporate from the leaves and so no condensation to form clouds which no precipitation would have occurred decreasing the earths water table (3) Implement laws to prevent deforestation Educate people about the effects of deforestation Promote afforestation Find alternative material then using wood in construction Refurbish old furniture [Any THREE] (3) Leads to a loss of biodiversity Habitat loss Decreases the earth s water table Reduces the water cycle Affects photosynthesis [Any THREE] (3) [12] TOTAL QUESTION 3: 40 TOTAL SECTION B: LIFE SCIENCES _ SEPTEMBER EXAMINATION

22 SECTION C QUESTION 4 Reproduction in Bryophytes: Gametophyte plants produce gametes (sperm and egg cells) by mitosis for sexual reproduction. Water is required to transport the sperm cell (antheridium) to the egg cell (archegonium). The sperm and egg cell fuse to form a diploid zygote during fertilization The zygote represents the new SPOROPHYTE GENERATION Zygote (sporophyte) develops a foot, seta and sporangium with a calyptra covering it. Sporophyte lives semi parasitically off the gametophyte for nutrients made during PHOTOSYNTHESIS Sporophyte undergoes meiosis to form a haploid spore. The calyptra falls off and spores are released. The spore germinates and forms a protonema (baby moss plant). The protonema then develops into an adult moss plant which represents the new GAMETOPHYTE GENERATION. [Any 13 Facts] How Pteridophytes are more terrestrially adopted than bryophytes: Bryophytes must grow and in water / damp environment and pteridophytes can survive in a shady environment Pteridophytes have true roots stems and leave and Bryophytes are thallus. Pteridophytes have xylem and phloem tissue whereas this is absent in Bryophytes [2X2 = 4] Content: (17) Synthesis (3) Criterion Relevance (R) Logical sequence (L) Comprehensive (c) Generally All information Ideas are arranged in a Comprehend the topic. provided is relevant to the topic logical sequenc Mark TOTAL SECTION C: 20 GRAND TOTAL: LIFE SCIENCES _ SEPTEMBER EXAMINATION

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