KULLEĠĠ SAN BENEDITTU Secondary School, Kirkop

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1 KULLEĠĠ SAN BENEDITTU Secondary School, Kirkop Mark HALF YEARLY EXAMINATION 2014/2015 Level YEAR 8 INTEGRATED SCIENCE TIME: 1h 30min Instructions to students: Answer ALL questions. Good English and orderly presentation are important. Read each question carefully. DO NOT WRITE ABOVE THIS LINE Name: Class: 1. The diagram below shows the structure of the Human Digestive System. a. Give the name of each organ labelled on the diagram. An example has been done for you. (4) Letter B A C D E Name of Organ Brain Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 1 of 10

2 b. Enzymes are found in organ D. Explain why enzymes are sometimes called chemical scissors. (1) c. Give the name of the acid present in organ D and give one important function (use) of this acid. Name: (1) Function: (1) d. Nutrients are absorbed in the body across organ E. What carries these nutrients to the rest of the body? (1) e. What happens to food which is not absorbed in the body? (1) [9 MARKS] 2. The plate below shows a variety of food groups in different portions. a. List three reasons why we need food. (3) b. From the plate, choose two foods rich in protein. (1) c. From the plate, choose two foods rich in carbohydrates. (1) d. Explain the meaning of the term balanced diet. (2) Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 2 of 10

3 e. Wholegrain foods, fruit and vegetables contain large amounts of fibre. Fibre has no energy value. Why should fibre be included in a balanced diet? (1) [8 MARKS] 3. This question is about the Human Breathing System and the Heart. a. Label the following diagram by choosing the correct word from the box below. (5) air sacs (alveoli) windpipe (trachea) diaphragm lungs ribs b. i. On the diagram above label with an X the position of the heart. (1) ii. During exercise the heart beats faster. When a person smokes, the heart also beats faster. Name a chemical found in cigarettes which makes the heart beat faster. (1) Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 3 of 10

4 c. The following steps describe what happens in the lungs during breathing. Put the steps in order using numbers. (4) Step Number Air is taken in through the nose or mouth. 1 Air passes through the bronchi into the lungs and through the bronchioles. Air finally reaches the alveoli (air sacs) where oxygen moves into the blood. Air moves down the trachea (windpipe). Carbon dioxide moves out of the blood into the alveoli and is breathed out. [11 MARKS] 4. Complete the following sentences with the appropriate word/s and use the same words to fill in the word fill below. a. The scientific name for harmful microbes is. (1) b. The protects us against harmful microbes. (1) c. are prescribed by a doctor to cure a bacterial infection. (1) d. is a mineral needed for strong bones and teeth. (1) e. is a vitamin present in citrus fruits e.g. oranges. (1) f. Fats are needed to keep inside the body. (1) a. b. c. d. e. f. H E A L T H [6 MARKS] Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 4 of 10

5 5. Read the following newspaper article and then answer the questions that follow. a. Underline the correct answer. Ebola is a virus which spreads from one person to another. It can be said that Ebola is an infectious / non-infectious disease. (1) b. The newspaper article states that Ebola spreads by touching body fluids e.g. spit of sick people or touching infected tropical animals. i. Give one way how the spread of Ebola can be avoided. (1) ii. Write one other way of how other microbes can spread. (1) c. Until this day, scientists have not yet created a vaccine to combat the Ebola virus. Briefly explain how vaccines work. (2) d. Several microbes cause disease but some are useful in food production. Which microbe do we use to make the following foods? (3) i. bread ii. yoghurt iii. cheese [8 MARKS] Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 5 of 10

6 6. This question is about Elements. a. Match the following elements with their symbols by putting the corresponding number in the box next to the symbol. Name Symbol i. Helium S ii. Oxygen He iii. Carbon K iv. Gold C v. Sulphur O vi. Potassium Au (6) b. These diagrams show the arrangement of atoms in different substances. i. Which diagrams show that the substance is an element? (2) ii. Explain your answer. (2) iii. Which diagram would show the arrangement of atoms in sodium chloride? (1) iv. When gold and iron are mixed together they do not combine. Which diagram shows what happens in this case? (1) [12 MARKS] Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 6 of 10

7 7. Fill in the missing words in the clues below to help you solve this crossword Clues down 1. are the smallest bits of elements. [5] 2. Non- metals are not malleable or. [7] 3. are usually insulators. [9] 4. The materials making up a can be easily separated. [7] Clues across 5. cannot be broken down into simpler substances by physical means. [9] 6. Iron, hydrogen and sodium are examples of. [8] 7. are usually hard and shiny. [6] 8. Metals are good of heat and electricity. [10] [8 MARKS] Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 7 of 10

8 8. This question is about physical and chemical changes. a. Choose from the following words to complete the sentences. irreversible chemical gas reversible physical i. When there is a change, no new substance is made and it is. (2) ii In a change, a or heat comes out or is taken in. (2) b. State whether the following are physical or chemical changes. i. glass breaking (1) ii. squeezing oranges to make orange juice (1) iii. burning toast (1) iv. melting butter for popcorn (1) v. corroding metal (1) vi. fireworks exploding (1) [10 MARKS] 9. The following pictures show the result of burning iron and magnesium. iron magnesium a. From the pictures, what shows that a chemical reaction is taking place? (1) b. When the reaction is complete, a new chemical is produced. True or false? (1) Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 8 of 10

9 c. These two reactions are very similar. Complete this table. Observations Iron Magnesium Heat comes out yes Light comes out yes Colour change From grey to orange Compound formed Iron oxide (4) d. During burning, iron and magnesium combine with another element. Name this element. (1) [7 MARKS] 10. This question is about Separating Techniques. Ben wanted to separate a mixture of sand and water and he used the apparatus below. a. Label the diagram using words from the box. (4) filtrate test tube filter paper residue funnel conical flask Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 9 of 10

10 b. i. Name the separating technique used in this case. (2) ii. Why can t you separate salt and water in this way? (2) iii. What separating technique would you use to separate salt and water? (2) c. Match the following: (5) chromatography magnet distillation by hand solvent Used to obtain water from a mixture of sea water Separates colours in ink Used to dissolve a chemical Used to separate blue and yellow balls Used to separate iron and plastic paper clips [15 MARKS] 11. Answer TRUE or FALSE and give a reason for your answer. i. Rain dissolves soil. Reason ii. Paint cannot be removed by water. Reason iii. When sugar is stirred in hot tea, it cannot be seen but it is still there. Reason [6 MARKS] END OF EXAM Kulleġġ San Benedittu Secondary School Kirkop Yr 8 Science Level Page 10 of 10