Half Yearly Exam 2016

Transcription

1 GOZO COLLEGE Secondary School KULLEĠĠ TA GĦAWDEX Skola Sekondarja Half Yearly Exam 2016 Year 8 Levels: 5-8 SCIENCE Time: 1:30min Name: Class: Year 8 Instructions to Candidates Answer all twenty questions. Write only on this paper. Do not spend too much time on any one question only. Good English and orderly presentation are important. Information to Candidates The mark of each question is written beside or at the end of each question. Each correct answer carries one mark. The total mark scored will be given as a percentage mark. Question Maximum Mark Question Paper total Maximum Final mark 100% Mark X 0.67 =

2 Q1. Look at the pictures. Then answer the questions on nutrients. (10 marks) fish pork chop butter walnut olive oil corn (Use examples from the pictures above) a) Name two foods rich in proteins. i. and ii.. b) Why are proteins important in our diet?. and.. c) Sugar and starch are rich in which nutrient?. d) Name two foods rich in fat. i. ii. e) Why are fats important in our diet?.. f) What are the hazards of too much fat in our diet? g) What do you understand by a balanced diet? Q2. People do not always eat a balanced diet. (3 marks) Draw one line from each fact about a person s diet to the organ it harms. Draw three lines Fact about the diet Not enough calcium Not enough fibre Too much fat Organ harmed heart intestine lung bones Q3. The table shows the mass of water, fat, fibre and vitamin C in 100 g of potato cooked in three different ways. (4 marks) Water in Fat in Fibre in Vitamin C g g g in mg 100g of chips a100 g of boiled potatoes 100g of potatoes baked in its skin Hardly any Hardly any a. Use the table to fill the blanks. i. Chips are crisper than boiled potatoes because chips contain less ii. Most of the fibre in a baked potato is in the.... Integrated Science Year 8 Track 5-8 February 2016 Page 2 of 12

3 b. Use the information in the table to work out how much vitamin C there is in: i. 200g of chips.... mg ii. 200g of potatoes baked in its skin.... mg Q4. People in different countries eat different amounts of starch. A scientist compared the amount of starch that people ate to the number of people with cancer of the large intestine. (5 marks) The scatter graph below shows her results. Look at the scatter graph China 300 Amount of starch eaten Finland Ireland Britain Netherlands United States Number of people, per , with cancer of the large intestine (a) (i) Which country had the greatest proportion of people with cancer of the large intestine?.. (ii) What conclusion could you come to about the effect of eating starch on getting cancer of the large intestine? (b) (i) Starch is a carbohydrate. Which two of the following foods are good sources of starch? Tick the two correct boxes. bread cheese fish chicken tomatoes pasta (ii) What other type of nutrient, needed as part of a balanced diet, keeps the intestine working well and prevents constipation? Tick the correct box. fat fibre minerals protein vitamins Integrated Science Year 8 Track 5-8 February 2016 Page 3 of 12

4 Q5. Fill in the blanks with the given key words. (7 marks) bones cereals constipation iron scurvy teeth vegetables a. is a mineral important in making red blood cells. b. Calcium is important for healthy and. c. Two foods rich in fibre are and. d. Fibre is important in our diet as it prevents. e. Vitamin C prevents a condition known as. Q6. a. Use the given key words to label the digestive system. (6 marks) anus - gullet - large intestine - mouth - small intestine - stomach A B E C F D b. Digestion can be mechanical (physical) or chemical. Mark the type of digestion represented by each function. (6 marks) Organ mouth stomach Small intestine Function teeth grind food saliva changes starch to sugar acids allow enzymes to break down food food mixed and squeezed Enzymes from pancreas complete digestion Bile from liver breaks fat into small drops Type of Digestion Mechanical Chemical Integrated Science Year 8 Track 5-8 February 2016 Page 4 of 12

5 Q7. a. Micro-organism can cause infections in the body. (10 marks) Draw straight lines to match each disease to the micro-organism which causes it and to the way the disease is spread. The first one has been done for you. Microbe Disease How disease is spread Bacteria Common flu Eating infected food Virus Food poisoning Coughing and sneezing Virus Athlete s foot Close contact Fungus Chicken pox Public showers Bacteria Tuberculosis Blood contact Virus AIDS Coughing and sneezing b. The body can defend itself against disease in a variety of ways. Draw straight arrows to match up each method of defence to the correct description from those listed below: (4 marks) Body defences Clotting of blood Skin Immune system Stomach acid Description chemical that kills most microbes made up of white blood cells that kills microbes stops most microbes from entering the body seals wounds quickly to prevent entry of microbe Q8. This question is about micro-organisms. Tick the correct box. (4 marks) i. Which is the smallest type of microbe? bacteria fungus virus ii. Which type of microbes are seen in the diagram? bacteria fungus virus iii. Which type of microbes are usually made up of branched threads? bacteria fungus virus iv. Which of the following micro-organisms help the bread to rise in baking? yoghurt starch yeast salt Integrated Science Year 8 Track 5-8 February 2016 Page 5 of 12

6 Q9. a) Micro-organisms can be useful to us. Name two useful types of microbes and write what they are these used for? (2marks) Name of useful microbe Where it is used b) Are antibiotics effective against influenza? Explain why. (2marks).. c) How can you lessen the risk of getting salmonella when you cook food which was frozen? (1 mark) d) Name two situations where you need to wash your hands: (2 marks) i.. ii.. e) Scurvy is a disease that sailors often got on long voyages. It was discovered that scurvy could be prevented by eating oranges and lemons. This suggests that scurvy is a disease caused by: tick the correct box. (1 mark) a microorganism exposure to sea air lack of exercise a nutritional deficiency Q10. The diagram shows part of the breathing system. Use the given key words to name the parts labelled A, B, C and D. (5 marks) alveolus diaphragm lung rib trachea E Q11. a. Crossmatch organ found in a human body system with function. (4 marks) Organ nose lungs diaphragm gas exchange Function muscle that controls breathing moistens and filters air Integrated Science Year 8 Track 5-8 February 2016 Page 6 of 12

7 b. Which human body system performs these functions? Tick the correct box. skeletal circulatory digestive respiratory c. The diagram below shows one alveolus and its blood supply. (3 marks) (i) Gas A enters the blood from the alveolus. Gas B leaves the blood and enters the alveolus. What are the names of gases A and B? Gas A is Gas B is (ii) Give one reason why it is easy for gases to pass across the wall of an alveolus Gas B Gas A Alveolus (air sac) tiny blood vessel d. The diagram below shows a nicotine molecule. It contains atoms of three elements. Nicotine in tobacco smoke enters the blood through the alveolus. (4 marks) (i) Nicotine is a compound. How does the diagram show this?. (ii) When nicotine in a cigarette is burned in air, nitric oxide is formed from the nitrogen in the nicotine. Look at the elements in nicotine. Give the names of two other compounds formed when nicotine burns in air. a... and b... (iii) Name one reason why smoking is a dangerous habit to health. Q12. Fill in the gaps with the given key words. (13 marks) atom carbon dioxide compound equation formula metals mixture molecule nitrogen non-metals Periodic simpler symbol Substances that cannot be broken down into anything are called elements. These are made up of only one type of. Each element is represented by a chemical. All the elements are shown in Integrated Science Year 8 Track 5-8 February 2016 Page 7 of 12

8 the table. The elements on the left side of this table are known as whilst those on the right are. When two or more elements chemically join together, a new type of substance is formed. Such a substance is called a and is represented by a. The smallest particle of a compound is called a. A chemical reaction can be shown by a word. A is made up of different substances NOT chemically combined together. For example, in air there are three gases mixed together: oxygen and are elements whilst is a compound. Q13. The diagram shows part of the Periodic Table. (7 marks) Use the symbols on the diagram to answer the following questions. a) Give the symbols for two metals.... and... b) Give the symbols for two non-metals.... and... c) Give the symbol for an element that is a gas.... d) Give the symbols for two elements that react to make lithium chloride.... and... Q14. a. The oldest coin in the world is nearly 3000 years old. Very old coins are often made from pure gold. What type of substance is pure gold? Tick the correct box. (1 mark) An element Compound Solvent A mixture This is a list of the properties of gold. A Shiny appearance B Very unreactive C Good electrical conductivity D Yellow colour Au Gold Integrated Science Year 8 Track 5-8 February 2016 Page 8 of 12

9 b. Use the letters A, B, C and D to answer the following questions. (3 marks) i) Which property explains why gold coins are not affected by oxygen in the air?... ii) Which two properties are true for all metals?. and. iii) Draw lines to match each metal to its symbol. Use the information in the table to help you. (3 marks) Element sodium iron lead Symbol Pb Na Fe iv) Silver has the symbol Ag. Suggest why the symbol for silver is not Si.... (1 mark) v) Circle the names of two other metals. (2 marks) sulphur zinc aluminium carbon nitrogen Q15. Three balloons are filled with three different gases. (10 marks) a) The diagrams show the particles of gas in each balloon. How do the arrangements of particles in the balloons show that they are gases?.... b) Tick the balloon which does not contain any molecules? argon oxygen carbon dioxide c) Tick the balloon which contains molecules of an element? argon oxygen carbon dioxide d) Tick the balloon which contains molecules of a compound? argon oxygen carbon dioxide Integrated Science Year 8 Track 5-8 February 2016 Page 9 of 12

10 e) i) Carbon dioxide is sometimes sold as dry ice. Dry ice is solid carbon dioxide. How is the arrangement of particles in dry ice different to the arrangement of particles in carbon dioxide gas?.. ii) The formula for carbon dioxide is CO2. What do the letters C and O stand for C =... O =. f) Mark the statements about the gases in the balloons true or false? Argon is a non-metal Statement True False Carbon dioxide molecules have more carbon atoms than oxygen molecules All of the balloons contain compounds Q16. Fill in the blanks by using some of the words listed below: (5 marks) solvent dissolving solution insoluble solute Some people cannot drink tea or coffee without adding sugar to it. The sugar disappears in the warm water. This process is known as... The water, which is the substance that makes the dissolving is called a. Sugar is called the... Since sugar dissolves in water it is... Not all solids can dissolve in water. Sand cannot dissolve in water and so it is.. Q17. (a) Samantha opened a tin of white paint. The paint consisted of a liquid and particles of titanium dioxide that are insoluble in the liquid. The paint had separated into two layers, as shown below. (4 marks) liquid Tick the correct box. Particle layer of insoluble titanium dioxide (i) What type of substance is the paint? a compound an element a mixture (ii) What type of substance is titanium dioxide? a compound an element a mixture (iii) Why did the particles of insoluble titanium dioxide sink to the bottom?.. Integrated Science Year 8 Track 5-8 February 2016 Page 10 of 12

11 (b) Samantha stirred the paint and used it to paint a window frame. She got some of the paint on the glass. Samantha could not get the paint off the glass with water. When she used a different liquid called white spirit the paint came off. Why could she remove the paint with white spirit but not with water?.. Q18. Use the words listed below to choose the easiest way of separating the following mixtures: (5 marks) filtration magnet distillation chromatography by hand boiling Mixture Separating method i ii iii iv v If you wanted to separate iron filings from sand Permanent marker ink is best separated by using If I want to separate mud from water To get salt from seawater To separate peas from dried beans Q19. a. Rock salt is a mixture. Pure salt can be separated from rock salt. Sentences A, B, C, D and E describe how pure salt can be obtained from rock salt. The sentences are not in the correct order. A Evaporate the water by heating B Mix the rock salt with water C Crush the rock salt D Stir to dissolve the salt E Filter the mixture Put the sentences A, B, C, D and E in the correct order. The first one has been done for you. C b. Does rock salt evaporate when its solution is heated? (5 marks) Integrated Science Year 8 Track 5-8 February 2016 Page 11 of 12

12 Q20. The diagram below shows the students arrangement of the glassware for carrying out an experiment. (8 marks) Thermometer Water out Y Glass tube X heat Water in Test tube a) What is the name of this separation technique? b) Which processes occur during this separation method? Tick the correct box. condensation then evaporation melting then boiling melting then evaporation evaporation then condensation c) Name the pieces of apparatus in the diagram labelled X and Y X is... Y is. d) Where in the diagram would you put the solution you want to separate?.. e) What is the purpose of the water that is flowing into and out of the piece of apparatus labelled Y?... f) Give the name of the colourless liquid that collects in the test-tube? g) Name the additional piece of laboratory equipment that is needed to carry out this experiment... THE END Integrated Science Year 8 Track 5-8 February 2016 Page 12 of 12