HERZLIA MIDDLE SCHOOL

Transcription

1 NAME TEACHER S COMMENT TEACHER CLASS MARK PERCENTAGE HERZLIA MIDDLE SCHOOL GRADE 7 NATURAL SCIENCE FINAL EXAMINATION 28 NOVEMBER 2014 TIME: 90 Minutes MARKS: 150 1

2 EXAMINERS: MR B.TSHADO & MRS J. AVIS MODERATOR MR B. FRAUENKNECHT INSTRUCTIONS: 1. There are 22 pages including: the cover page, Answer Sheet, a blank page, a page with graph paper and a coloured page. Make sure you have all of them. Pull off the coloured page (flowers) and use it to answer Question Answer all questions in blue or black ink. 3. Read each question carefully before answering it. 4. Pay attention to the mark allocation. 5. Plan your time carefully. 6. All the diagrams should be done in pencil and labelled in blue or black ink. 7. Write neatly and legibly. 8. Use the Answer Sheet for Question Write in full sentences. No one word answer will be accepted. 10. Do not shade or colour or use highlighters on graphs. 2

3 MULTIPLE CHOICE ANSWER SHEET NAME: CLASS: Multiple Choice (use pencil only) Choose the answer, which you consider most appropriate and cross the corresponding letter on this Answer Sheet. E.g. If your answer to 1.3 is D, indicate your choice like this: 1.3 A B C D If more than one cross appears in any line, the answer will be marked wrong. 1.1 A B C D 1.2 A B C D 1.3 A B C D 1.4 A B C D 1.5 A B C D 1.6 A B C D 1.7 A B C D 1.8 A B C D 1.9 A B C D 1.10 A B C D 1.11 A B C D 1.12 A B C D 1.13 A B C D 1.14 A B C D 1.15 A B C D 3

4 SECTION A (LIFE & LIVING; MATTER & MATERIALS; ENERGY & CHANGE) 50 QUESTION 1: MULTIPLE CHOICE Four questions are provided as possible answers to the following questions. Each question has only one correct answer. Write only the letter (A-D) next to the question number ( ) on the Answer Sheet provided. 1.1 Which of the following is not a renewable source of energy? (2) A. Coal B. Uranium C. Solar D. Petrol 1.2 Energy that travels from the Sun to Earth is by (2) A. convection B. radiation C. absorption D. a miracle 1.3 Which of the following is a non-renewable source of energy? (2) A. Tidal power B. Biomass C. Geothermal D. Uranium 1.4 Factor that is changed by the investigator in an experiment: (2) A. dependent variable B. independent variable C. controlled variable D. hypothesis 4

5 1.5 Factor that remains constant in an experiment: (2) A. dependent B. independent C. controlled D. hypothesis 1.6 The energy of the air conditioner in summer is transferred in the school classrooms by (2) A. Radiation B. Convection C. Conduction D. Absorption 1.7 Which South African company generates 98% of South Africa s electricity? (2) A. B. C. Eskom Sasol D. South Africa Wind Energy 1.8 Which is the best reason why tidal or wave power is not suitable for South Africa? (2) A. Waves are usually too strong B. There are no waves usually, except at Jeffrey s Bay C. Huge propellers on long stands are needed D. The rise and fall of tides is not sufficient to meet the demand of South Africa s electricity grid 5

6 1.9 Which of the following is a mixture? (2) A. gold B. pure water C. air D. table salt (compound sodium chloride) The following diagram is required for 1.10 and The female parts of the flower are: A. A, B, C, D and E (2) B. A, B, C, D C. C, D, E D. Only C 1.11 The part that will develop into the seed is: (2) A. A B. E and C C. C D. D 1.12 The following seeds are dispersed by: (2) A. wind B. dogs C. birds D. water 6

7 1.13 The part of the flower that protects the developing bud is the: (2) A. ovary B. petal C. sepal D. anther 1.14 The part of the flower that produces the pollen is the: (2) A. ovary B. petal C. sepal D. anther 1.15 Which of the following is not part of the innermost whorl of the flower? (2) A. stamens B. style C. pistil D. stigma 15 x 2 = 30 7

8 QUESTION 2: TERMINOLOGY Give the correct term for each of the following descriptions. 2.1 The scientific name given to the flowering plant group. (1) 2.2 Source of energy that cannot be used up. (1) 2.3 Fuels that were made from living organisms millions of years ago. (1) 2.4 Solid that does not dissolve in liquid. (1) 2.5 Process of changing a liquid to a gas. (1) 2.6 Mixture that consists of a solid and a liquid. (1) 2.7 Transfer of pollen from the male parts of a flower to the female parts. (1) 2.8 The part of the flower that develops into the fruit. (1) 2.9 Fusion of the male sex cell with the female sex cell. (1) 2.10 Process when a seed starts to grow. (1) 1 x 10 = 10 8

9 QUESTION 3: MATCH THE COLUMNS Choose the word/phrase from COLUMN B that BEST matches the word/phrase/ in COLUMN A. Write only the letter (A-M) next to the question number ( ). CORRECT ANSWER COLUMN A COLUMN B 3.1 insulator A waste from plants and animals 3.2 coconut B pigments 3.3 Joule C allows the flow of heat easily 3.4 organic waste D unit for measuring energy 3.5 chromatography E does not allow heat to pass through easily 3.6 Liebig condenser F salt 3.7 zygote G waste from plastics, glass and metal 3.8 disperse H separating sand and water 3.9 unisexual I distillation 3.10 filtration J floats on sea water K L scatter fertilized egg M separate male and female plants 1 x 10 = 10 9

10 SECTION B: LONG QUESTIONS(LIFE & LIVING; ENERGY & CHANGE) 100 QUESTION Classify each of the following energy sources as either renewable or non-renewable and list the type of energy shown in each picture. (4) A B Koeberg C D Renewable or Non- Renewable Type of Energy After the recent load shedding Eskom is investigating increasing the amount of renewable energy for the Western Cape. Imagine that they have asked you to be on the advisory committee. Decide on the best renewable energy source for the Western Cape. Give reasons for your choice. (4) 10

11 4.2.2 For each of the following sources of energy give one advantage and one disadvantage of the source: (10) Biomass Advantage: Disadvantage: Geothermal Advantage: Disadvantage: Fracking Advantage: Disadvantage: Hydroelectricity Advantage: Disadvantage: Coal Advantage: Disadvantage: 11

12 QUESTION 5 31 Explain the three ways in which heat energy is being transferred in the example of a pot placed on a stove to boil water. metal 5.1 (2) 5.2 (2) 5.3 (2) 5.4 What is the main way that energy is transferred in the water? (1) What is a convection current? (3) 12

13 5.5.2 What chemical did we use in class to see the convection current? (1) What is the method of heat transfer used in a geyser to heat water? (1) 5.6 Barbara Bloch cooked soup for her family s Shabbat dinner in the pot on page Why did she burn her hand? (1) Suggest a solution to Barbara s problem for her meal the following Friday. (1) 13

14 5.7 Four years ago a South African entrepreneur invented the wonder box during a power cut. This is a bean bag filled with small beads made out of polystyrene. The food is heated in a pot to boiling point. Then a lid is placed on the pot and then the pot is placed in the wonderbox. cardboard box bean bag filled with many polystyrene beads Eskom had load shedding one Friday afternoon, but Lois Kaimowitz was not concerned even though she had a lot of people coming for dinner as she had just bought a wonderbox. Explain how this allowed her to continue cooking the food. (2) For the next Shabbat meal, Lois replaced the beads in the same bean bag with the same size metal beads. She cooked exactly the same meal Do you think the meal would cook faster or slower than the previous Friday? Explain your answer. (3) What is the independent variable in Lois s investigation? (1) What is the dependent variable in Lois s investigation? (1) Name one controlled variable in Lois s investigation. (1) 14

15 5.8 The Grade 7s did investigation to compare how different materials conduct heat. They used a metal, glass, wood and polystyrene mugs/cups. The same volumes of boiled water were added to each mug/cup and each student put their palm around each mug/cup. Their results were recorded in the table below. Table 1: Table showing the results of an Insulation experiment 12/11/2014 Mug/Cup Materials Degree of heat determined by feeling Metal (no enamel coating) Very hot Polystyrene Slightly warm Thick wood Cool no heat felt Glass Hot Give the aim of the investigation. (1) Give three variables that must be controlled in this investigation. (3) Give the independent variable in this investigation. (1) Which material is the best insulator? Explain your answer. (2) Define the term conductor. (2) 15

16 QUESTION Define the terms: Energy (2) Potential energy (1) Kinetic energy (1) 6.2 Complete the table below for potential energy. (6) Type of Potential Energy Gravitational Potential Energy Explanation Example Energy trapped in chemicals Stretching an elastic band 6.3 What type of potential energy is used in the following examples: A wind-up toy car. (1) 16

17 6.3.2 A boy blowing a vuvuzela. (1) 6.4 Study the diagrams below and answer the questions that follow If the roller coaster is still, what form of energy does it contain? (1) If it is moving, what type of energy does it possess? (1) If this light is off, what type of energy does it have? (2) If switched on, what energy does it have? (1) 17

18 QUESTION 7 34 Constantin Eick and Ryan Lipman photographed flowers in the Herzlia Middle school fynbos garden. Some of these are on the coloured sheet on the last page of this exam. Use this sheet to help you answer the following questions. 7.1 Divide flowers A to F into two groups insect or bird pollinated. Explain how you made your choices. (5) Insect: Bird: Explanation: 7.2 What are the black markings called on Flower C and what is their function? (2) 7.3 Use the blank page (page 19) provided to draw a scientific diagram of the flower of Pelargonium graveolens. Ensure that you follow the diagram rules. (10) 18

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20 7.4 The boys recorded the pollinators they saw in the table below. Table 2: Pollinators sighted in the Fynbos Garden on 11 August 2014 Type of Pollinator Number Butterflies 9 Bees 3 Wasp Use the graph paper on page 21 to draw a bar graph to show this information. Ensure that you follow the rules for drawing graphs. (10) What is a pollinator? (2) Why are pollinators so important to plants? (2) If the number of bees in the Western Cape decreased, how would this affect humans? Give three points. (3) 20

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