BC Science 8 Workbook Answers

BC Science 8 Workbook Answers Unit 1: Cells and Systems Chapter 1 The cell is the basic unit of life. Section 1.1 Answers Section 1.1 Summary Pages 2 3 1. A microscope helps you focus two objects or details that are close together and makes an object seem larger than it is. 2. The object will appear 16 larger than it is. Analyzing Information Characteristics of living things Page 4 Accept all reasonable answers. Sample answers (can be in any order): 1. responds to its environment we respond to hunger by eating 2. needs energy plants need sunlight, water, and carbon dioxide to make food 3. grows children grow taller, replace cells 4. reproduces salmon lay eggs 5. gets rid of wastes that build-up in its body exhaling carbon dioxide The compound light microscope Page 5 1. light source 2. stage 3. objective lenses 4. eyepiece 5. arm 6. coarse focus knob 7. fine focus knob Cloze activity Microscopes Page 6 1. compound light microscope 2. eyepiece 3. coarse focus knob 4. fine focus knob 5. objective lenses 6. light source 7. resolving power 8. upside down, reversed 9. electron micrograph Observing living things Page 7 1. B 2. F 3. C 4. G 5. E 6. A 7. D 8. B 9. D 10. A 11. C 12. A 13. B Section 1.2 Answers Section 1.2 Summary Pages 8 9 1. Prokaryotic cells do not have organelles with a membrane around them. 2. cell wall, chloroplasts Parts of cells Page 10 A. cell membrane B. nucleus C. mitochondria D. vacuoles E. cytoplasm F. mitochondria G. cytoplasm H. nucleus I. chloroplast J. vacuole K. cell wall L. cell membrane Inside a cell Page 11 1. organelle 2. cell membrane 3. cytoplasm 4. nucleus 5. mitochondria 6. vacuoles 7. cell wall 8. chloroplasts 9. eukaryotic 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 1

10. prokaryotic 11. bacteria 12. viruses True or false? Page 12 1. True 2. False. Some organisms are composed of only one cell. OR All organisms are composed of one or more cells. 3. False. Plant cells use chloroplasts to trap the Sun s energy. 4. False. Plant cells are cells surrounded by a cell wall. OR Prokaryotic cells are cells with organelles that do not have a membrane around them. 5. True 6. True 7. True 8. False. Bacteria are examples of prokaryotic cells. OR Plant cells and animal cells are examples of eukaryotic cells. Cells Page 13 1. D 2. D 3. B 4. A 5. C 6. D 7. F 8. B 9. H 10. A 11. E 12. C 13. D Section 1.3 Answers Section 1.3 Answers Pages 14 15 1. Diffusion moves substances that a cell needs from outside the cell to inside the cell. Diffusion also moves wastes from inside the cell to outside the cell. 2. Water will move into the cell. Vocabulary Crossing the cell membrane Page 16 1. concentration 2. diffusion 3. a selectively permeable membrane 4. osmosis 5. diffusion 6. a selectively permeable membrane 7. osmosis 8. diffusion 9. diffusion Applying Knowledge Osmosis and diffusion Page 17 Accept all reasonable answers. Sample answer: Diffusion (left circle) can move particles, such as gas Similarities (middle) move substances into and out of cells use a selectively permeable membrane substances move from high concentration to a low concentration Osmosis (right circle) moves water only Examples of osmosis Page 18 A. Water particles move in, causing the cell to swell. The plant cell swells beyond its normal size. B. Water particles move in and out of the cell at the same rate. The plant is in its normal state. No change occurs. C. Water particles leave the cell by osmosis causing the cell to shrink. The plant cell membrane shrinks away from the cell wall. Diffusion, osmosis, and the cell membrane Page 19 1. C 2. C 3. C 4. C 5. A 6. E 7. A 8. B 9. C Chapter 2 Human body systems work independently and together. Section 2.1 Answers Section 2.1. Summary Pages 20 21 1. A tissue is a group of cells that have the same structure and play the same role. 2. nerve, muscle, connective, epithelial Vocabulary Eleven body systems Page 22 1. respiratory 2. skeletal 3. nervous 2 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

4. excretory 5. endocrine 6. digestive 7. integumentary 8. reproductive 9. immune 10. muscular 11. circulatory Vocabulary Puzzle Body systems puzzle Page 23 Across 2. organ 3. tissue 7. reproductive Down 1. integumentary 4. respiratory 5. nervous 6. cell 8. digestive Name the system Page 24 1. respiratory system 2. digestive system 3. skeletal system 4. nervous system 5. muscular system 6. circulatory system Body systems Page 25 1. I 2. G 3. A 4. L 5. K 6. H 7. C 8. J 9. B 10. M 11. E 12. F 13. C 14. A 15. D 16. C 17. B 18. B Section 2.2 Answers Section 2.2 Summary Pages 26 27 1. carbohydrates, proteins, fats, vitamins, minerals 2. ingesting, digesting, absorbing, eliminating Know your nutrients Page 28 1. energy 2. pasta, brown rice 3. Protein; fish, nuts 4. cell membranes; energy 5. butter, oil 6. calcium, iron 7. vitamin C, vitamin D 8. digestive 9. excretory Illustrating Concepts Stages of digestion Page 29 The diagram should include the following concepts. Each section should be a different colour. 1. ingesting at top of the digestive tract 2. digesting at the stomach area 3. absorbing at the small intestine 4. eliminating from large intestine to rectum Vocabulary Looking inside digestion and excretion Page 30 1. E 2. G 3. B 4. A 5. F 6. I 7. D 8. H 9. C 10. K The digestive and excretory systems Page 31 1. B 2. C 3. A 4. A 5. A 6. B 7. A 8. D 9. B 10. G 11. C 12. A 13. F 14. D Section 2.3 Answers Section 2.3 Summary Pages 32 33 1. arteries 2. Gas exchange takes place between the alveoli and the capillaries. Applying Knowledge Follow the blood through the heart Page 34 Labels and flow should reflect Figure 2.23 of page 84 in the student textbook. 1. right atrium 2. right ventricle 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 3

3. lungs 4. left atrium 5. left ventricle 6. arteries to whole body Vocabulary Respiration match-up Page 35 1. C 2. K 3. E 4. A 5. I 6. B 7. J 8. D 9. H 10. F Interpreting illustrations Blood vessels Page 36 A. artery thick-walled blood vessels that move blood rich with oxygen to all the cells of the body B. capillaries very thin blood vessels that link arteries with veins. Oxygen diffuses from capillaries into cells. Carbon dioxide diffuses from cells into capillaries. C. vein thinner-walled blood vessels that bring blood back to the heart and lungs so it can be enriched with oxygen again. The circulatory and respiratory systems Page 37 1. A 2. C 3. B 4. C 5. A 6. B 7. D 8. H 9. D 10. B 11. E 12. G 13. F 14. C 15. I Chapter 3 The immune system protects the human body. Section 3.1 Answers Section 3.1 Summary Pages 38 39 1. The immune system s two lines of defence are to keep pathogens out of the body (the skin) and to attack pathogens (innate and acquired response). 2. A pathogen is a living thing or substance that causes a disease. An antigen is a non-living thing that is foreign to the body and that triggers an immune response. Cloze activity Looking at the immune system Page 40 1. pathogens 2. infectious 3. immune 4. first 5. second 6. white blood cells 7. innate 8. antigens 9. antibodies 10. active immunity Illustrating Concepts Infectious disease Page 41 Answers will vary. Sample answers: Direct contact: shaking hands, sharing drink containers Indirect contact: being near someone who sneezes or coughs Water and food: consuming infected food or water Animal bites: being bitten by an animal Extension Defence in Action Page 42 Answers will vary but might include steps showing recognition of pathogens, keeping pathogens out of the body, production of antibodies, attacking of pathogens, disposing of pathogens, and immunity. The immune system Page 43 1. E 2. B 3. G 4. A 5. C 6. F 7. A 8. C 9. A 10. D 11. B 12. A 13. A Section 3.2 Answers Section 3.2 Summary Pages 44 45 1. People are given vaccines so that their bodies will have antibodies to defend them if they are exposed to the live form of the disease. 2. You should keep your immune systems healthy because it keeps all the other body systems healthy. Disorders of the immune system Page 46 1. vaccine, dead 2. antibodies, antigens 3. live 4. memory 5. allergy 6. allergic reaction, histamine 4 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

7. antihistamine 8. allergen 9. HIV, helper T cells 10. B cells, killer T cells (Note: either order is correct) True or false? Page 47 1. False. If you have already been vaccinated you may need to be vaccinated again. 2. False. HIV is transmitted through semen or in blood. 3. False. A vaccine is a dead form of a disease pathogen. 4. False. An allergen causes an allergic reaction. 5. True 6. False. AIDS is caused by a virus called HIV. 7. True 8. True Illustrating Concepts Show what you know Page 48 Students should choose one of the following points to illustrate: Eat a well-balanced diet. Brush your teeth, shower or bathe, and wash your hands often. Keep your home clean. Avoid tobacco and other non-prescription drugs. Get plenty of rest and exercise. Keep your vaccinations up to date. Do not engage in activities that involve sharing body fluids with others. Factors affecting the immune system Page 49 1. D 2. F 3. C 4. A 5. B 6. A 7. D 8. D 9. B 10. D 11. A 12. A Unit 2: Optics Chapter 4 Many properties of light can be understood using a wave model of light. Section 4.1 Answers Section 4.1 Summary Reading checks Pages 50 51 1. The rest position of a water wave is where the water would be if it were still. 2. The frequency of a wave is measured in hertz. Hertz (Hz) means cycles per second. Vocabulary Features of a wave Page 52 1. crest 2. trough 3. amplitude 4. wavelength 5. rest position 6. Amplitude is the height of a wave crest or depth of a wave trough from its rest position. 7. The crest is the highest part of a wave. 8. The trough is the lowest part of a wave. 9. The wavelength is the distance from crest to crest or from trough to trough (the distance from one point on a wave to the same point on the next wave). 10. For a water wave, the rest position is where the water level would be if it were still. Analyzing Information Characteristics of waves Page 53 1. 4 m 2. 2 m 3. Wave B 4. Wave A 5. amplitude 6. Wave Y 7. Wave X 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 5

True or false? Page 54 1. False. Waves transfer energy forward. 2. True 3. False. A crest is the highest point in a wave. OR A trough is the lowest point in a wave. 4. False. The wavelength is the distance from crest to crest OR from trough to trough. (The wavelength is also the distance covered by one point on a wave to the same point on the next wave, such as one complete crest plus one complete trough.) 5. True 6. False. The larger the amplitude, the more energy is transported by the wave. OR The smaller the amplitude, the less energy is transported by the wave. 7. False. Frequency is the number of motions that occur in a given time. OR Amplitude is the height of a wave crest (or depth of a wave trough) from its rest position. 8. True 9. False The wavelength of a wave increases as frequency decreases. OR The wavelength of a wave decreases as frequency increases. Properties of waves Page 55 1. E 2. C 3. A 4. F 5. D 6. D 7. C 8. B 9. B 10. B Section 4.2 Answers Section 4.2 Summary Pages 56 57 1. Refraction is the bending of a wave between one medium and another. 2. A red ball looks black in the dark because there is no light for the ball to reflect or absorb. The ball itself does not produce light. Colour your world Page 58 1. ROY G BIV (red, orange, yellow, green, blue, indigo, violet) 2. white 3. white 4. cyan 5. yellow 6. magenta Facts about visible light Page 59 1. The different colours come from the refraction of white light. 2. The colours all have different wavelengths and therefore are bent by different amounts. 3. Light refracts or bends when it passes from one material to another. 4. Red has the longest wavelength. 5. Violet has the shortest wavelength. 6. Another prism can be placed, in reversed orientation, in the path of the refracted light. This will cause it to combine again into white light 7. Blue has a higher frequency than yellow because it has a shorter wavelength. 8. A violet dress appears to be violet in sunlight because it reflects violet and absorbs colours other than violet from the sunlight. 9. Red, green, and blue are three colours that can combine to produce all the colours of the rainbow. Visible light Page 60 1. wave model of light 2. visible light 3. refraction 4. wavelengths, frequencies (either order) 5. colour 6. prism 7. refracted 8. spectrum 9. ROY G BIV 10. reflected 11. absorbed Properties of visible light Page 61 1. G 2. C 3. E 4. F 5. B 6. A 7. D 8. D 9. B 10. C 11. D 12. B Section 4.3 Answers Summary Pages 62 63 1. The visible spectrum is part of a larger spectrum of waves called the electromagnetic spectrum. 6 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

2. Infrared waves are used to heat food, in remote controls, and to read CD-ROMS. Illustrating Concepts The electromagnetic spectrum Page 64 Examples will vary. Accept all reasonable answers. Sample answers: 1. Radio waves: broadcasting radio and television signals, MRI 2. Microwaves: microwave ovens, communication with satellites 3. Infrared waves: used to keep food warm in restaurants with heat lamps; used in remote controls for televisions; used in computers to read CD-ROMS 4. Ultraviolet rays: used for making vitamin D in humans; used to study fingerprints with fluorescent powder; used to kill bacteria in food, water, and medical supplies 5. X rays: used by dentists to photograph teeth; used by doctors to photograph bones; used by airports to see inside a passenger s suitcase; used to inspect cracks inside high performance jet engines without taking the engine apart, and to photograph the inside of machines 6. Gamma rays: used for radiation therapy to kill cancer cells True or false? Page 65 1. True 2. False. Electromagnetic radiation includes visible and invisible light waves. OR Electromagnetic radiation includes visible light waves and radio waves, infrared waves, ultraviolet rays, X rays, and gamma rays. 3. False. Some microwaves are a type of radio waves and infrared waves. Microwaves are also a category on their own. 4. False. Gamma rays have more energy than X rays. OR X rays have more energy than ultraviolet, infrared, or radio waves. 5. True 6. True 7. False. Communicating with satellites is an application of microwaves (or radio waves). 8. True More than meets the eye Page 66 1. electromagnetic spectrum 2. electromagnetic radiation 3. radiant energy 4. infrared waves 5. radio waves 6. microwaves 7. gamma rays 8. frequency 9. ultraviolet rays Visible light and the electromagnetic spectrum Page 67 1. E 2. A 3. D 4. B 5. D 6. D 7. C 8. C 9. B 10. A Chapter 5 Optical systems make use of mirrors and lenses. Section 5.1 Answers Section 5.1 Summary Pages 68 69 1. Light may be reflected, transmitted, or absorbed. 2. Angle of incidence = angle of reflection Applying Knowledge Getting in light s way Page 70 1. Sample answers: SURFACES DESCRIPTION EXAMPLES transparent translucent opaque all or most of the light is transmitted some light is transmitted all or most of the light is absorbed or reflected no light passes through 2. 1. translucent; scattered 2. translucent; scattered 3. opaque; reflected 4. opaque; absorbed 5. transparent; transmitted air, plastic wrap, water, glass, overhead transparency light rays are scattered in all directions skin, clouds, waxed paper, fingernail, lampshade, frosted bathroom window rock, brick, book, wood, wall, aluminum can 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 7

Illustrating Concepts Predictable behaviour of light Page 71 1. Sketches should show the rays passing through the surface. 2. Sketches should show only one or two rays passing through the surface, and the rest scattered in different directions. 3. Sketches should show the rays reflecting at the same angle as they struck the surface. 4. Sketches should show the angle of incidence as the angle between the incoming ray and the normal. The angle of reflection should be shown between the outgoing ray and the normal. 5. Sketches should show the ray bending toward the normal in the water. 6. Sketches should show the ray bending away from the normal in the air. Light can reflect and refract Page 72 1. ray model of light 2. transparent 3. translucent 4. opaque 5. incidence 6. plane mirror 7. refraction 8. refracted ray The ray model of light Page 73 1. D 2. B 3. C 4. A 5. B 6. C 7. C 8. A 9. D Section 5.2 Answers Section 5.2 Summary Reading Check Pages 74 75 1. Reflecting surface of the concave mirror curves inward and the reflecting surface of the convex mirror curves outward. 2. Light rays that are converging are coming together. Light rays that are diverging spread apart. Mirrors Page 76 Sample answers: 1. plane mirror: allows you to see yourself 2. concave mirror: enlarges a person s face so it is easier to see small details 3. convex mirror: increases the field of view for the driver 4. concave mirror: enlarges the inside of the mouth so that the dentist can see your teeth more easily 5. convex mirror: increases the field of view and allows all the store s aisles to be seen at the same time 6. concave mirror: enlarges the parts of a watch or jewellery piece so that it is easier for the jeweller to see the tiny parts 7. convex mirror: increases the field of view for the driver 8. concave mirror: widens the area in which light is projected 9. concave mirror: enlarges a person s face so it is easier to see small details 10. plane mirror: allows you to see yourself Applying Knowledge Flat mirrors and curved mirrors Page 77 reflecting surface Plane Mirror Concave Mirror (object near to mirror) Mirror, mirror, on the wall Page 78 1. reflect 2. images 3. plane mirror 4. concave mirror, focal point 5. converging 6. upside down Concave Mirror (object far from mirror) Convex Mirror flat inward inward outward size same size Larger smaller smaller orientation upright upright upside upright down shape same different different different location behind behind in front behind example Sample answer: bathroom mirror Sample answer: shaving mirror, makeup mirror Sample answer: flashlight Sample answer: security mirror 8 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

7. upright 8. convex mirror, behind 9. diverging Using mirrors to form images Page 79 1. A 2. B 3. E 4. D 5. C 6. A 7. B 8. D 9. D 10. C 11. B Section 5.3 Answers Section 5.3 Summary Pages 80 81 1. When light rays pass through a concave lens they diverge and do not meet at a focal point. 2. The focal length is the distance from the centre of the lens to the focal point. Light rays and lenses Page 82 1. smaller, upside down 2. larger, upside down 3. smaller, upright 4. smaller, upright Applying Knowledge Concave lenses and convex lenses Page 83 Draw the lens: concave (lenses are thinner in the middle than at the edge) convex (lenses are thicker in the middle than at the edge) Do light rays converge or diverge? concave (light rays pass through concave lens diverge and never meet at the focal point) convex (light rays pass through convex lens converge and come together at focal point) Is the image upright or upside down? concave (upright) convex (depends on where the object is relative to the focal point; can be upright or upside down) Is the image smaller or larger than the object? concave (smaller than object) convex (depends on where the object is relative to the focal point; can be smaller or larger) Vocabulary Lenses puzzle Page 84 Across 3. away from 5. convex 6. smaller 9. length 13. converge 14. thinner Down 1. larger 2. point 4. upside down 7. toward 8. upright 10. thicker 11. diverge 12. concave Using lenses to form images Page 85 1. B 2. E 3. D 4. C 5. B 6. B 7. C 8. B 9. A 10. B 11. A Chapter 6 Human vision can be corrected and extended using optical systems. Section 6.1 Answers Section 6.1 Summary Pages 86 87 1. cornea pupil? lens? retina 2. near-sightedness, far-sightedness, astigmatism Vocabulary Parts of the eye Page 88 1. a (iris) 2. d (sclera) 3. c (pupil) 4. e (retina) 5. g (optic nerve) 6. b (lens) 7. f (cornea) 8. cornea 9. sclera 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 9

10. pupil 11. iris 12. lens 13. retina 14. optic nerve Inside the eye Page 89 1. The cornea does most of the focussing of the light rays that pass through the eye. OR The lens does some of the focussing of the light rays that pass through the eye. 2. The light rays that pass through the eye converge. 3. In bright light, the iris makes the pupil smaller to allow less light to enter. OR In dim light, the iris makes the pupil larger to allow more light to enter. 4. The human eye has a convex lens. 5. The lens of the eye produces an inverted or upside down image. 6. Electrical signals are sent to the brain through the optic nerve. 7. People who are far-sighted cannot bring nearby objects into focus. OR People who are near-sighted cannot bring distant objects into focus. 8. Near-sightedness can be corrected by using a concave lens. OR Far-sightedness can be corrected by using a convex lens. Illustrating Concepts Vision problems Page 90 Condition Description Cause Where is image formed? Nearsightedness Farsightedness nearby objects are clear, but distant objects are fuzzy distant objects are clear, but nearby objects are fuzzy eye has a longer shape than normal eye eye has a shorter shape than normal eye image focusses in front of the retina image focusses behind the retina Correction of condition corrected with concave lens (or surgery) corrected with convex lens (or surgery) Condition Description Cause Where is image formed? Astigmatism fuzzy vision caused by an irregularly shaped cornea Human vision Page 91 1. E 2. D 3. A 4. B 5. A 6. C 7. A 8. C 9. B 10. D 11. C Section 6.2 Answers Section 6.2 Summary Pages 92 93 1. convex 2. Laser light can be used for surgery and in optical fibre technology. Using optical systems Page 94 1. microscope, convex 2. magnifies 3. refracting 4. reflecting, plane 5. binoculars 6. laser light 7. optical fibres 8. total internal reflection cornea has an irregular shape image focusses on more than one point on the retina Compare a telescope and microscope Page 95 1. eyepiece lens 2. focal point 3. objective lens 4. light from distant object 5. light from light source Correction of condition corrected with lenses or surgery Extension Now you see it! Page 96 Designs will vary. Look for an understanding of how mirrors and lenses create an image, and of how laser light and optical fibres work. 10 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

Extending human vision Page 97 1. E 2. F 3. B 4. D 5. A 6. D 7. B 8. B 9. D 10. B 11. C Unit 3: Fluids and Dynamics Chapter 7 Kinetic molecular theory explains the characteristics of solids, liquids, and gases. Section 7.1 Answers Section 7.1 Summary Pages 98 99 1. When it expands, volume increases (gets bigger). 2. The particles move faster and farther apart, becoming a liquid. Solids, liquids, and gases Page 100 Solid Liquid Gas Shape fixed shape not fixed; takes the shape of the container Gas: The particles of the gas should be moving around quickly and bouncing off the wall of the jar. Liquid: The particles of the liquid should be a little closer together. Solid: The particles of the solid should be tightly packed together, perhaps shown as a cube. Expand and contract Page 101 1. mass, volume, matter 2. rises not fixed; takes the shape of the container Volume fixed volume fixed volume not fixed; fills all the space in the container Spaces between particles Movement of particles little space; particles are packed tightly together so that they are side by side can only vibrate particles are touching, but able to move past one another can slip and slide past one another large spaces can move freely and quickly in all direction in the container 3. melting, sublimation 4. evaporation, solidification 5. condensation, deposition 6. vibrate, slide past each other, move around quickly 7. slower, contracts 8. kinetic molecular theory What s the matter? Page 102 1. sublimation 2. melting 3. evaporation 4. solidification 5. condensation 6. deposition States of matter Page 103 1. A 2. C 3. B 4. A 5. A 6. C 7. A 8. B 9. B Section 7.2 Answers Section 7.2 Summary Pages 104 105 1. Density describes the spacing of the particles in a material. There is more space between the particles of a gas, so a gas is less dense than a liquid. 2. You can put the object into a full container of water and collect the water that spills out. That water is equal to the volume of the object. Go with the flow Page 106 1. fluids 2. density 3. particles 4. float 5. denser, water Change of state Condensation gas to liquid released Deposition gas to solid released Evaporation liquid to gas added Melting solid to liquid added Solidification liquid to solid released Sublimation solid to gas added Heat added or released 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 11

6. mass, volume 7. displacement 8. g/ml, g/cm 3 Illustrating Concepts Dense, denser, densest Page 107 Beaker: Substances should appear in this order from top to bottom: gasoline, rubbing alcohol, vegetable oil, glycerol, and corn syrup. Tank: Floating objects are: cork, ice, block of wood Objects at the bottom of the tank are: gold ring, marble Applying Knowledge Density detective Page 108 1. D = m V = 26.76 3 = 8.92 g/ cm 3 The old coin must be made of copper. 2. D = m V = 5.28 2 = 2.64 g/ cm 3 You found a quartz. 3. D = m V = 107 5 = 21.4 g/ cm 3 The ring must be made of platinum. 4. D = m V = 184.32 (3 4 6) = 2.56 g/ cm 3 The paperweight must be made of marble. Fluids and density Page 109 1. C 2. F 3. C 4. A 5. D 6. C 7. A 8. C 9. A Chapter 8 Fluids are affected by forces, pressure, and heat. Section 8.1 Answers Section 8.1 Summary Pages 110 111 1. Contact forces only act on objects in direct contact. Action-at-a-distance forces can act on objects that are not touching. 2. Weight is the amount of force that gravity exerts on the mass of an object. Mass measures the amount of matter in an object. What is a force? Page 112 1. force 2. contact, action-at-distance 3. friction, tension, elastic 4. gravitation, magnetic, static electricity 5. newtons 6. mass, weight 7. balanced 8. unbalanced Name the force Page 113 1. elastic force contact 2. gravitation action-at-a-distance 3. magnetic action-at-a-distance 4. static electricity action-at-a-distance True or false? Page 114 1. F. A force can set a motionless object in motion. 2. T 3. T 4. F. Friction force works to slow down or stop motion due to surfaces rubbing against each other. OR Tension force is exerted on a rope when it is pulled from either end. 5. F. Gravitation pulls objects toward each other. OR Elastic force is exerted when a spring returns to normal shape after it has been stretched. 6. F. An example of static electricity is lightning. OR An example of magnetic force is magnets attracting metal, such as iron. 7. F. The weight of an object measures how strongly gravity pulls on that amount of matter. 8. T 9. T 10. T Forces Page 115 1. D 2. B 3. F 4. C 5. E 6. A 7. A 8. D 9. C 10. D 11. C 12. C 13. B Section 8.2 Answers Section 8.2 Summary Pages 116 117 1. There is more space between the particles of a gas so it can be compressed. Liquids and solids do not have as much space between their particles. 12 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

2. pressure (P) = f orce ( F) F or P = area ( A) A What is pressure? Page 118 1. pressure 2. compression, decreases 3. gases 4. pressure, explosion 5. pressure, force, area 6. N, m 2 7. pascal, Pa 8. kilopascal, kpa Illustrating Concepts Compression Page 119 The diagrams should compare the underfilled balloon and the balloon when compressed. The volume of the balloon is reduced but the number of molecules remains the same. There is a greater concentration of gas molecules in the compressed balloon and therefore the pressure is higher. The diagrams should show that the speeds of the gas molecules increase as the can is heated. The pressure increases until the can explodes; and then the gas molecules can escape into the surroundings. Applying Knowledge Under some pressure Page 120 1. P = F A = 147 N (1 m 0.75 m) = 196 Pa 2. P = F A = 700 N (2 m 2 m) = 175 Pa 3. P = F A = 300 N (0.75 m 0.5 m) = 800 Pa 4. P = F A = 600 N (0.5 m 0.5 m) = 2400 Pa Pressure Page 121 1. D 2. B 3. D 4. C 5. A 6. A 7. D 8. C 9. D 10. C 11. B 12. B 13. D Section 8.3 Answers Section 8.3 Summary Pages 122 123 1. Honey has a greater viscosity because it pours much more slowly. 2. In cohesion, particles of the same fluid stick together. In adhesion, particles of a fluid stick to something else. Properties of fluids Page 124 1. fluid 2. viscosity, thinner, thicker 3. greater, slowly 4. flow rate 5. decreases 6. increases 7. cohesion 8. surface tension 9. adhesion Analyzing Information Viscosity of different substances Page 125 1. substance C 2. 30ºC 3. substance B 4. substance A 5. 32 cm/s Applying Knowledge How does it flow? Page 126 Definition fluids that do not flow easily Characteristics have high viscosity have slow flow rates flow thickly and smoothly resist movement and flow particles that make up the fluid are larger therefore causing greater resistance to flow Examples answers will vary, but might include ketchup, molasses, syrup, motor oil, honey, toffee, lava flowing from a volcano Non-examples answers will vary, but might include milk, soft drinks, vinegar Viscosity, adhesion, and cohesion Page 127 1. D 2. C 3. A 4. B 5. E 6. A 7. D 8. C 9. B 10. B 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 13

Chapter 9 There are both natural and constructed fluid systems. Section 9.1 Answers Section 9.1 Summary Pages 128 129 1. Pressure increases with depth because there is more fluid pressing down on the fluid at a lower level. 2. It will sink because the downward pulling force of gravity on the object is greater than the upward pushing of the buoyant force. The force of gravity is larger. All that pressure Page 130 1. From the top hole, the fluid will fall close to the container because there is little pressure near the top of the container. The fluid will be forced much farther from the bottom hole of the container than the top hole because the pressure is greater at the bottom of the container. 2. a. Air pressure is greater at the base of a mountain. b. There is more air pressure at the bottom of the mountain because air is more dense near sea level. 3. a. 2 atm of pressure on the scuba diver at 10 m below sea level. b. 25 m = 3.5 atm of pressure on the scuba diver at 25 m below sea level. There is less pressure on the scuba diver at the surface of the waves. The deeper the scuba diver goes into the water, the more water will be pressing down upon him. Therefore, the water pressure increases with depth. There is higher pressure on the scuba diver at a depth of 25 m below sea level (the pressure is 1 atm at sea level, so going down 25 m results in (1 atm + 2.5 atm) Applying Knowledge Fluid pressure Page 131 1. floating 2. sinking 3. sinking 4. rising 5. rising 6. floating Putting on the pressure Page 132 1. lower, higher 2. lower, higher 3. increases 4. 1 atm 5. 1 atm 6. buoyancy 7. density 8. buoyant 9. buoyant, gravity 10. gravity, float Fluids under pressure Page 133 1. D 2. E 3. B 4. C 5. D 6. B 7. B 8. A Section 9.2 Answers Section 9.2 Summary Pages 134 135 1. A hydraulic system is a device that uses pressure to apply a force through a liquid to move something else. (i.e., toothpaste, car brakes) 2. A pneumatic system is a device that uses pressure to apply a force through a gas to move something else. (i.e., filling tires, dental drill) Fluids at rest and fluids in motion Page 136 1. fluid 2. hydraulics 3. hydraulic system 4. hydraulic system 5. pumps 6. pressure 7. liquid 8. hydraulic multiplication 9. pneumatics 10. pneumatic system Applying Knowledge Comparing systems Page 137 Answers will vary, but might include any of the examples below. 14 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

Hydraulic system system uses liquids force is transmitted along the liquid causing motion force applied to the system can be multiplied pressure is applied at one location and the force performs a task in another location can use a pump operates devices from a distance Pneumatic system system uses gas (e.g., air) enclosed gas transmits a force causing motion Both pressure is created force is transmitted a fluid is used 2. Answers may vary, but might include: Hydraulic systems: pipes providing water to the house squeezing a tube of toothpaste garden hose spraying out water dentist s chair mechanic s piston used to lift cars for repair Pneumatic systems: drills used by dentists filling tires with air jackhammer pneumatic brakes (air brakes) on large trucks and buses True or false? Page 138 1. F. Hydraulics is the study of pressure in liquids. 2. F. Hydraulic systems produce pressure that moves through a liquid. 3. T 4. F. A pneumatic system uses a device to compress the air so pressure builds up. 5. F. Pumps are important parts of hydraulic systems. 6. T 7. F. Pneumatic systems use gas in an enclosed system under pressure. Constructed fluid systems Page 139 1. B 2. D 3. C 4. A 5. F 6. A 7. C 8. C 9. D 10. D (also accept A). Section 9.3 Answers Section 9.3 Summary Pages 140 141 1. The circulatory system has a pump (heart), pipes (blood vessels), and a fluid under pressure (blood). 2. In the respiratory system, air under pressure is moved from one place to another place. Vocabulary Puzzle Fluid systems puzzle Page 142 Across 1. breathing 5. circulatory 11. sphygmomanometer 12. blocked 13. blood pressure Down 2. respiratory 3. blood 4. blood vessels 6. infections 7. diaphragm 8. asthma 9. heart 10. arteries Pressure in the human body Page 143 1. circulatory 2. heart, blood 3. pump 4. pressure 5. sphygmomanometer 6. blood vessels, blood pressure 7. respiratory 8. breathing 9. inhale, diaphragm 10. higher Extension A world of fluid systems Page 144 Collages may vary. Examples of hydraulic systems: heart, gall bladder, salivary gland, river, stream, volcano, hot spring, aquifer. Examples of pneumatic systems: lungs, hurricanes. 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 15

Natural fluid systems Page 145 1. B 2. D 3. A 4. E 5. C 6. D 7. B 8. A 9. D 10. A 11. C Unit 4: Water Systems on Earth Chapter 10 The water cycle plays a vital role on Earth. Section 10.1 Answers Section 10.1 Summary Pages 146 147 1. evaporation, condensation, melting, solidification, sublimation, deposition 2. A hydrologist is a person who studies the water cycle, and where and how water is found on Earth. The water cycle Page 148 1. water vapour, liquid, ice 2. water cycle 3. the Sun 4. evaporation, solidification 5. freezing point 6. condensation, deposition 7. melting, sublimation 8. hydrologist Analyzing Information Changing state Page 149 1. evaporation: heat added; from liquid into gas 2. melting: heat added; from solid into liquid 3. condensation: heat taken away; from gas into liquid 4. solidification: heat taken away; from liquid into solid 5. deposition: heat taken away; from gas into solid 6. sublimation: heat added; from solid to gas. 7. solid 8. sublimation 9. condensation 10. liquid 11. solidification 12. melting The water cycle Page 150 1. Evaporation: ocean water is heated by the Sun. Water vapour rises into the atmosphere 2. Condensation: air is cooled and water droplets form. 3. Precipitation: depending on conditions, clouds release water as rain, snow, or another form of precipitation. Distribution of water Page 151 1. D 2. C 3. B 4. D 5. A 6. D 7. B 8. A 9. A 10. D 11. D Section 10.2 Answers Section 10.2 Summary Page 152 153 1. Salt can come from the ground, rocks and volcanoes. 2. The ocean is denser than fresh water because of the amount of salt in it. Ocean Water Page 154 1. dissolve 2. ocean floor 3. land 4. salinity 5. North and South Poles 6. Equator 7. Less 8. sodium chloride 9. density 10. greater Salt water Page 155 1. Water that falls to the ground seeps into the ground or flows into streams and rivers. 2. As water moves over the ground and rocks on its way to the ocean, it picks up salt. 3. Volcanoes on land send substances into the air that fall into the ocean. Volcanoes on the ocean floor add substances directly to the water. 16 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

4. In some parts river water dilutes the salt. Near the Poles, salt is left behind when water freezes. Near the equator, salt is left behind when water evaporates. 5. Density is the amount of mass in a given volume of material. 6. Ocean water has a higher density than fresh water. 7. Fresh water has a higher freezing point than ocean water. Analyzing Information Dissolved solids Page 156 1. others 2. potassium 3. calcium 4. magnesium 5. sulfate 6. sodium 7. chloride 8. 85.6% 9. 14.4% How ocean water differs from fresh water Page 157 1. C 2. B 3. D 4. B 5. B 6. A 7. A 8. A 9. C Section 10.3 Answers Section 10.3 Summary Pages 158 159 1. Ground water comes from rain that falls on land. 2. Water in glaciers is unavailable for use by people because it is frozen in snow and ice. Fresh water Page 160 1. run-off, ground 2. gravity 3. drainage basin 4. ground water, wells 5. glaciers 6. alpine 7. continental 8. crevasses, icebergs 9. receding Extension From sky to sea Page 161 Look for an understanding that water from rain travels to the ocean through run-off. True or false? Page 162 1. F: Water runs along Earth s surface because gravity pulls it from higher places to lower places. 2. F: A drainage basin drains run-off into a stream, river, or lake. 3. T 4. F: Most of the fresh water on Earth is frozen. 5. F: Glaciers are found in the Arctic and the Antarctic, and in the mountains. 6. F: Crevasses are deep cracks in glaciers. OR Icebergs are large chunks of ice. 7. T Sources of fresh water Page 163 1. C 2. F 3. E 4. B 5. D 6. D 7. D 8. A 9. A 10. A 11. C Section 10.4 Answers Section 10.4 Summary Pages 164 165 1. weathering, erosion, deposition 2. rapids, landslides, striations (other examples may also be acceptable) Shaping Earth s surface Page 166 1. physical, chemical, biological 2. erosion, deposition 3. acidic 4. calcium carbonate, cave 5. sinkhole, karst 6. rapids 7. striations The effect of water Page 167 1. weathering, erosion, deposition 2. Weathering breaks down rock into smaller pieces. 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 17

3. Water collects in the pores and cracks of rocks and then freezes, expands, and breaks the rock apart. 4. Acidic rainwater dissolves substances on Earth s surface. Caves, sinkholes, and karst are other examples. 5. Weathering breaks down rocks and erosion moves the rock from one place to another. 6. A cave forms when acid rainwater dissolves calcium carbonate in rock. 7. A karst forms when rock is dissolved near the surface of the ground and the surface collapses. 8. The water pushes rocks from one place to another in rapids. 9. When rain soaks the sides of steep hills, gravity can cause a landslide. 10. When moving water slows down and when moving ice melts, the rocks they carry are released. These deposits build up as time passes. When this happens in the place where a river enters a lake or ocean, the deposits form a fan shape called a delta. Vocabulary Puzzle Earth s surface puzzle Page 168 Across 4. cave 6. striations 7. erosion 9. acidic 11. deposition 12. biological Down 1. physical 2. karst 3. weathering 5. landslide 8. rapids 10. delta 13. chemical Water s effect on shaping Earth s surface Page 169 1. A 2. I 3. D 4. C 5. E 6. G 7. H 8. B 9. F 10. B 11. D 12. D 13. A Chapter 11 Oceans control the water cycle. Section 11.1 Answers Section 11.1 Summary Pages 170 171 1. Tectonic processes are the movement of the plates and the way they interact. 2. continental slope, continental shelf, continental rise The ocean floor Page 172 1. tectonic plates, molten rock 2. tectonic processes 3. molten rock, mid-ocean ridges 4. trenches 5. continental shelf, continental slope 6. continental rise, turbidity currents 7. submarine canyons 8. abyssal plain, continental margin Features of the ocean floor Page 173 1. The ocean ridge forms when two plates are pushed apart by the underlying molten rock pushing up. 2. The ocean trench forms when the ocean plate pushes under the continent plate. 3. A. continental margin B. continental rise C. abyssal plain D. continental slope E. continental shelf F. submarine canyons Extension On the bottom of the ocean Page 174 Students answers should describe features such as abyssal plain, continental shelf, continental slope, continental rise, submarine canyon, and turbidity currents. Some students may also describe tectonic processes. 18 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

Ocean basins Page 175 1. G 2. E 3. C 4. F 5. D 6. B 7. H 8. C 9. A 10. A 11. B 12. B 13. A 14. C Section 11.2 Answers Section 11.2 Summary Pages 176 177 1. A surface current flows in the top 200 m of the ocean. A deep ocean current flows deeper than 200 m. 2. The water bulges on the side facing the Moon, causing high tide. The water level falls between the two high tides, creating low tides. Currents and waves Page 178 1. ocean current, surface current, deep ocean current 2. wind action 3. temperature, salinity, density 4. upwelling 5. plankton 6. swells 7. tectonic forces, tsunami 8. tides 9. spring tide 10. neap tide True or false? Page 179 1. F. An ocean current is a large amount of ocean water that moves in one direction. 2. F. Surface currents are caused by wind action, the spin of Earth, and the shape of the continents. 3. F. Deep ocean currents are caused by salinity differences and temperature differences. 4. F. Density differences draw cooler, nutrient-rich water from deep in the ocean to the surface. 5. F. The movement of cool water to the surface of the ocean is called an upwelling. 6. T 7. F. Plankton are microscopic plants and animals. 8. T Illustrating Concepts The ocean in motion Page 180 1. The Sun and moon should be shown aligned with Earth. The new moon should be between Earth and the Sun. The full moon should be on the opposite side of the Earth, farthest away from the sun. Bulges should be drawn on the sides of the Earth closest to the two moons in the diagram, to indicate spring tides. 2. The Sun and moon should be at right angles to each other, with the Earth forming the apex. The first quarter moon should be at a 90 degree angle above the Earth, and the third quarter moon should be at a 90 degree angle below. Bulges should be drawn on the sides of the Earth closes to the two moons in the diagram, to indicate neap tides. Ocean currents Page 181 1. B 2. D 3. A 4. E 5. C 6. G 7. D 8. C 9. A 10. B 11. D 12. C Section 11.3 Answers Section 11.3 Summary Page 182 183 1. Weather is the state of the atmosphere at a given time. Climate is all the features of the weather for a certain region averaged over a long time. 2. During el Niño, places that usually get wet and cold weather get dry and warm weather. La Niña brings wetter weather to places that usually are dry. Convection and climate Page 184 1. weather 2. climate 3. equator, Poles 4. equator 5. heat capacity 6. convection 7. Gulf Stream 8. mountains 9. la Niña 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 19

Oceans, weather, and climate Page 185 1. It takes a long time for water to heat up and cool down. 2. Weather is the state of the atmosphere at a given time. It includes features such as temperature, wind, air pressure, and moisture. 3. Climate is all the features of the weather for a certain region averaged over a long time. 4. Convection transfers heat by forming currents of rising heated material and sinking cooler material in a fluid such as air or water. 5. The Gulf Stream current helps to keep the British Isles and northern Europe warmer in the winter and cooler in the summer. 6. The coastal mountains prevent moist ocean air from reaching the interior of British Columbia. 7. El Niño is the period when the Pacific winds get weak and the warm water current starts to move east toward South America. 8. La Niña is a period during which upwelling causes unusually cold water to rise to the surface off the coast of South America near the equator. Convection transfers heat Page 186 1. c 2. d 3. b 4. c 5. a 6. d 7. e Oceans and climate Page 187 1. D 2. B 3. A 4. E 5. G 6. C 7. B 8. A 9. A 10. B 11. C 12. B Chapter 12 Changes in water quantity and quality can affect living things. Section 12.1 Answers Section 12.1 Summary Pages 188 189 1. Plants can grow in lakes and ponds wherever sunlight can reach. 2. An estuary is where a river flows into an ocean, so it can only occur along a coast. Different kinds of freshwater environments Page 190 1. Streams and rivers are both fast moving waterways. The main difference between streams and rivers is size. Streams are smaller than rivers. 2. Rushes, cattails and water lilies grow at the edges of lakes and ponds. 3. Phytoplankton are tiny plants and plant-like organisms that make their own food from sunlight. Zooplankton are tiny animals and animal-like organisms that eat phytoplankton. 4. Wetlands store water, which helps to prevent flooding. The roots of the plants help make the ground more stable. Many kinds of birds and fish breed in these areas. Insects and many other kinds of animals live in or visit wetlands as part of their life cycle. 5. Estuaries are rich in nutrients that come from the rivers and the ocean. These nutrients feed a wide variety of plants, fish, birds, and mammals. Fresh water Page 191 1. (any order) lakes, ponds, wetlands, rivers, streams, estuaries 2. sunlight, nutrients, depth, fast, oxygen 3. phytoplankton 4. standing 5. flooding, stable 6. estuaries, brackish Illustrating Concepts Living in fresh water Page 192 Answers will vary but might include some of the following: Figure 1: Pond Water movement: shallow water, slow movement Organisms: plankton, plants, amphibians, fish, larger fish, mammals, birds Depth: Sunlight reaches to the bottom of the pond. Figure 2: Wetlands Water movement: slow movement or standing water Organisms: insects, rodents, fish, birds Figure 3: River Water movement: fast moving Organisms: weeds, mosses, algae, plants, insects, snails, worms, fish 20 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited

Figure 4: Estuary Water movement: depends on river action and tidal action from ocean Organisms: eel grass, trout, otter, owls, herons Freshwater environments Page 193 1. C 2. F 3. B 4. A 5. D 6. C 7. D 8. B 9. C 10. C 11. D Section 12.2 Answers Section 12.2 Summary Page 194 1. The pelagic zone is the first 4000 m of water below the surface of the ocean. 2. The benthic zone is the cold, dark part of the ocean that is deeper than 4000 m from the surface. Living in saltwater Page 196 1. pelagic, benthic 2. pelagic 3. 200 m 4. sunlight, twilight, midnight 5. sunlight 6. twilight 7. benthic 8. abyssal, hadal 9. abyssal 10. hadal 11. light Illustrating Concepts Ocean water environments Page 197 Answers may vary slightly but should include the following: 1. Sunlight zone Sunlight penetrates, plants can grow 2. Twilight zone Dim light, no plants grow 3. Midnight zone No light reaches this zone 4. Abyssal zone Bottom of ocean, freezing cold temperatures and enormous water pressure 5. Hadal zone Found in deepest ocean trenches. Freezing cold, enormous water pressure. Food webs Page 198 harlequin duck squid zooplankton phytoplankton harlequin duck herring zooplankton phytoplankton toothed whale squid zooplankton phytoplankton toothed whale seal squid zooplankton phytoplankton toothed whale seal herring zooplankton phytoplankton toothed whale herring zooplankton phytoplankton Saltwater environments Page 199 1. B 2. E 3. A 4. G 5. D 6. D 7. B 8. C 9. D 10. C 11. A Section 12.3 Answers Section 12.3 Summary Pages 200 201 1. point source: dumping garbage/ oil spill non-point source: pesticides on lawns 2. Acid precipitation is rain or snow that carries acids from pollution back down to Earth. Water quality Page 202 1. Pollution is a term that refers to harmful materials that are released into the environment. 2. Point sources are sources of pollution that come from one source, such as an oil spill, or garbage dumped from a boat. 3. Non-point sources of pollution are from many different sources, such as pesticides added to lawns. 4. When it rains, some of the pesticide can get washed into the soil and be absorbed. The pesticide may find its way into ground water. And the ground water may feed into a stream or river. The stream or river then carries the pesticide into a lake or an ocean. 5. The wind carries pollutants from smokestacks and cars high into the air. They mix and dissolve with water vapour, and they form strong acids, which return to Earth as acid rain and acid snow. 2006 McGraw-Hill Ryerson Limited Workbook Answers MHR 21

Water pollution Page 203 1. point sources 2. oil spill 3. non-point sources 4. pesticide 5. pollutants 6. oil 7. pollutants, acids 8. acid precipitation, acidic 9. ph, 5.0 10. pollutants Applying Knowledge Sources of pollution Page 204 Answers and drawings will vary, but might include any of the following: Point source: landfill leak; mill pumping out waste water; oils spills; leaks from underground containers for gas stations; sewage systems and waste water treatment plants; garbage being dumped Non-point source: industrial spills; pesticides; fertilizers; animal waste; oil and chemicals from industrial, commercial, and residential sources; sewage leakage; increased water run-off; air pollution Water quality and its effects on living things Page 205 1. C 2. A 3. E 4. D 5. A 6. D 7. D 8. D 9. D 22 MHR Workbook Answers 2006 McGraw-Hill Ryerson Limited