Year 8 Half Yearly exam – 2018 /75 Multiple choice (1 mark each) 1. Organisms made up of only one cell are known as A. Multicellular B. Unicellular C. Epithelial D. Epidermal 2. The role of cell division in multicellular organisms is: A. Growth only B. Repair only C. Reproduction only D. All of the above 3. Which organ belongs to the respiratory system: A. Heart B. Stomach C. Trachea D. Thymus 4. What is the missing substance in the following equation: Glucose + oxygen water + ___________ + energy A. B. C. D. Amino acid Carbohydrate Fat Carbon dioxide 5. The ___________ system involves the movement of gases, nutrients, water and the removal of cell wastes. A. Digestive B. Circulatory C. Reproductive D. Excretory 6. Approximately how many high and low tides are there in a period of 24 hours? A. 1 high and 1 low B. 2 highs and 2 lows C. 1 high and 2 lows D. 2 highs and 1 low 7. A solar eclipse occurs when: A. The earth is between the sun and the moon B. The sun is between the earth and the moon C. The moon is between the earth and the sun D. All of the above 8. A year on earth is when: A. The moon rotates on its axis B. The moon revolves around the earth C. The earth rotates on its axis D. The earth revolves around the sun 9. The earth is tilted __ degrees A. 23 B. 24 C. 23.5 D. 24.5 10. What type of tide occurs in the following situation: A. B. C. D. Spring Neap High Full 11. _____________ are the charged parts of an atom A. Only electrons B. Only protons C. Electrons and protons D. Electrons and neutrons 12. In typical electrostatic experiments, protons cannot be gained or lost from an atom because they are ____________ A. More massive than electrons B. Negatively charged C. Tightly bound to the nucleus D. Loosely bound outside the atom’s nucleus 13. The force of gravity that acts upon an object is referred to as the _______ of the object: A. Pressure B. Density C. Mass D. Weight 14. Two factors affecting the magnitude of the force of gravity between 2 objects are: A. Mass and distance B. Distance and weight C. Mass and matter D. Weight and Mass 15. An apple falling from a tree branch happens because of a gravitational force. What type of force is this? A. Contact B. Non-contact C. Physical D. None of the above 16. A rocket accelerating upward from a launch pad is an example of ________ A. Balanced forces B. Zero forces C. Unbalanced forces D. Net forces 17. When 2 pieces of steel are pushed together they push away from each other. The force that does this is: A. Elastic force B. Electrostatic force C. Gravity Force D. Magnetic force 18. The force between electrostatic like charges is: A. Attraction B. Repulsion C. No force D. Constant force 19. The 2 main functions of roots in a plant are: A. Storage and photosynthesis B. Anchor and storage C. Photosynthesis and respiration D. Water absorption and anchorage 20. The blood vessel which allows diffusion across the vessel wall is: A. Veins B. Capillaries C. Arteries D. Alveolus Short answer questions (marks given next to each question) 21. Label the diagram below: (5 marks) __________________ __________________ __________________ __________________ __________________ 22. In the space below, describe (and/or draw): A) a historic model of the solar system (2 marks) B) the scientific evidence that was used to reject the historic model of the solar system (2 marks) 23. Identify 2 ways in which an object can acquire an electrostatic charge (2 marks) ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 24. Describe, giving 2 examples, why surface area is important for maintaining a human as a functioning organism (3 marks) ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 25. Circle the correct vessel for the description given: A) B) C) D) E) F) G) H) Carry blood from the heart to the tissues One cell thick walls to allow exchange of materials Blood at high pressure Many valves to prevent back-flow Blood usually oxygenated Thick walls with elastic layers to resist high pressure Blood usually deoxygenated Blood cells can only pass through in single file (8 marks) Arteries/veins/capillaries Arteries/veins/capillaries Arteries/veins/capillaries Arteries/veins/capillaries Arteries/veins/capillaries Arteries/veins/capillaries Arteries/veins/capillaries Arteries/veins/capillaries 26. Using the diagram below, explain why the moon appears differently to us at different times of the month. (2 marks) __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ 27. Describe what photosynthesis and cellular respiration have in common. (2 marks) __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ 28. Label the diagram from the words in the table below: (6marks) A. F. B. C. D. E. Capillary Deoxygenated blood Oxygenated blood Answers: A._____________________ D.____________________ To pulmonary artery To pulmonary vein Alveolus B._________________________ E._________________________ Carbon dioxide oxygen venule C._____________________ F._____________________ 29. In the space provided below, describe how an electroscope can be permanently charged (positive or negative) (hint: diagrams may be useful) (5 marks) 30. Use the tide track below for the next 3 questions: A) What is the time and height of the morning high tide on Tuesday? (1 mark) ___________________________________________________________________________ B) Which is bigger of the 2 high tides on Tuesday? What causes this difference? (2 marks) ___________________________________________________________________________ ___________________________________________________________________________ C) What is the time of the second high tide on Monday? How much later is this than the first high tide? (2 mark) ___________________________________________________________________________ 31. Describe 2 everyday situations where gravity acts as an unbalanced force (2 marks) ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 32. Explain an experiment that could demonstrate the behaviour of charged objects when they are brought close to each other (You may use diagrams). (4 marks) 33. Using the diagram below, explain how seasons are caused. (4 marks) __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ 34. Identify 3 parts of blood and their functions in the table below: Part Function (3 marks)