Evidence of Plate Tectonics 6.1.a, Page 2 1. Choice B is correct. Plate tectonics states that huge plates of rock move over the surface of the Earth. Choice A is incorrect because landmasses on Earth are separated by ocean. Choice C is incorrect because the continents move with the plates on which they are located. Choice D is incorrect because plate boundaries do not coincide with continental margins. 2. Choice A is correct. Plate tectonics explains the process by which the continents slowly moved long distances over millions of years. Choice B is incorrect because the process of erosion is not part of the theory of plate tectonics. Choice C is incorrect because coastlines do change over time. Choice D is incorrect because plate tectonics does not explain weather events such as hurricanes. 3. Choice C is correct. Most major earthquakes, volcanoes, and mountain ranges appear along plate boundaries, where the plates push together, pull apart, or slide past each other. Choice A is incorrect because not all plate boundaries occur at the edges of continents. Choice B is incorrect because major earthquakes, volcanoes, and mountain ranges occur on many continents, not just North and South America. Choice D is incorrect because most earthquakes, volcanoes, and mountain ranges occur where plates meet, not in the middle. 4. Choice D is correct. When the continents split apart and moved, they carried with them the rocks and organisms that existed at that time. Choice A is incorrect because the continents are not all the same. Choice B is incorrect because there is no evidence that islands once linked all the continents. Choice C is incorrect because there is no evidence that the continents appeared in their present locations all at once. 5. Choice A is correct. When the continents formed one huge landmass, the land that is now Greenland was in the tropics. Choice B is incorrect because tropical plant seeds would not germinate in the Arctic region. Choice C is incorrect because Earth s climate varies with latitude. Choice D is incorrect because fossils are not typically transported across the ocean.
Earth s Layers 6.1.b, Page 4 1. Choice C is correct. The crust consists of a thin layer of cool rock that makes up Earth s surface. Choice A is incorrect because the core is Earth s innermost layer and consists of hot metal. Choice B is incorrect because the mantle lies below the crust, is thick, and consists of hot rock. Choice D is incorrect because the asthenosphere is a layer of soft rock in the mantle. 2. Choice D is correct because temperature, pressure, and density all increase with increasing depth. The other choices are incorrect because they are not the best answer. 3. Choice A is correct because the inner core is a ball of solid metals. Choice B is incorrect because the metals in the inner core are solid, not liquid. Choice C is incorrect because the inner core consists of metals, not rock, and is not soft and tarlike. Choice D is incorrect because the inner core consists of metals, not rock, and is hot, not cool. 4. Choice A is correct because the mantle consists of hot rock and lies between the crust and the core. Choice B is incorrect because the mantle does not consist of liquid metal. Choice C is incorrect because it describes the crust, not the mantle. Choice D is incorrect because the mantle does not consist of soft metal and does not lie between the inner and outer core. 5. Choice B is correct. The crust and upper mantle make up a layer of hard rock called the lithosphere. Choice A is incorrect because the lithosphere is not the same as the core. Choice C is incorrect because the lithosphere does not contain the entire mantle, only the upper part of it. Choice D is incorrect the lithosphere does not contain all three layers of Earth. 6. Choice D is correct because the asthenosphere consists of the hot, soft rock in the mantle. Choice A is incorrect because the asthenosphere does not consist of hard rock and is not located in the core. Choice B is incorrect because the rock in the mantle is soft, not hard. Choice C is incorrect because the asthenosphere is not located in the crust.
Plate Movement 6.1.c, Page 6 1. Choice D is correct. Convection is the transfer of heat from one place to another by movement. Choices A, B, and C are incorrect because convection deals with the transfer of heat energy, not electric charge, chemical energy, or steam. 2. Choice A is correct. In a convection current, circulation occurs as a hot material rises, cools, and sinks. Choice B is incorrect because a cool material would not rise. Choices C and D are incorrect because they do not focus on temperature. 3. Choice C is correct. Convection currents in the asthenosphere drag the lithospheric plates along. Choice A is incorrect because the rock in the asthenosphere is not liquid. Choice B is incorrect because friction would slow movement rather than promote it. Choice D is incorrect because the convection currents occur in the asthenosphere, not the inner core. 4. Choice A is correct. The lithospheric plates move a few centimeters a year. Choices B, C, and D are incorrect because the distances are too large. 5. Choice D is correct. Over millions of years, the accumulated distance that the plates move measures thousands of kilometers. Choices A, B, and C are incorrect because the distances are too small.
Earthquakes and Volcanoes 6.1.d, Page 8 1. Choice C is correct. A large break in Earth s crust is called a fault. Choice A is incorrect because lava is molten rock that has reached Earth s surface. Choice B is incorrect because magma is molten rock within Earth. Choice D is incorrect because a seismic wave is a vibration caused by an earthquake. 2. Choice B is correct. Earthquakes are caused by the sudden movement of large blocks of rock along a fault. Choice A is incorrect because seismic waves are part of an earthquake, not the cause. Choice C is incorrect because it describes a volcanic eruption. Choice D is incorrect because it describes the way volcanic mountains form. 3. Choice D is correct. Most faults, earthquakes, and volcanoes occur along plate boundaries. Choices A, B, and C are incorrect because they are not complete and so are not the best answer. 4. Choice A is correct. Magma that reaches Earth s surface is called lava. Choices B and C are incorrect because they name types of volcanoes. Choice D is incorrect because a fault is a break in Earth s crust. 5. Choice D is correct. A shield volcano has a broad, flat shape and forms from the buildup of layers of lava. Choice A is incorrect because it describes a cinder cone. Choice B is incorrect because a shield volcano forms from layers of lava, not rock fragments. Choice C is incorrect because a shield volcano is broad and flat, not cone-shaped. 6. Choice A is correct. A composite volcano is cone-shaped and forms from layers of lava and layers of rock fragments. Choice B is incorrect because it describes a cinder cone. Choice C is incorrect because it describes a shield volcano. Choice D is incorrect because a composite volcano is cone-shaped, not broad and flat.
Results of Plate Motion 6.1.e, Page 10 1. Choice D is correct. The plate motion at all types of boundaries produces earthquakes. Choices A, B, and C are incorrect because they indicate that earthquakes occur at only one type of plate boundary. 2. Choice B is correct. The sliding of one plate under another at a subduction zone produces strong earthquakes and explosive volcanic eruptions. Choice A is incorrect because divergent boundaries typically have small earthquakes and mild volcanic eruptions. Choice C is incorrect because volcanic eruptions do not typically occur at transform boundaries. Choice D is incorrect because not all types of plate boundaries feature explosive volcanic eruptions and strong earthquakes. 3. Choice D is correct. Earthquakes, active volcanoes, and mountain ranges are all found along the Ring of Fire. Choices A, B, and C are incorrect because they are incomplete and so none of them is the best answer. 4. Choice C is correct. The Ring of Fire is located around the perimeter of the Pacific Ocean, which also roughly marks the boundary of the Pacific Plate. Choices A, B, and D are incorrect because each one names an incorrect ocean. 5. Choice A is correct. When two plates with continental crust collide at a convergent boundary, the rock crumples and bends, forming folded mountains. Choice B is incorrect because plates do not collide at divergent boundaries. Choice C is incorrect because folding occurs when plates with continental, not oceanic, crust collide. Choice D is incorrect because folded mountains do not form at divergent boundaries, and two plates with oceanic crust do not collide at these boundaries.
California Geology 6.1.f, Page 12 1. Choice C is correct. The North American and Pacific Plate meet in California and have produced the San Andreas Fault. Choices A, B, and D are incorrect because the plates that are named do not share a boundary that cuts across California. 2. Choice C is correct. The San Andreas Fault occurs where the Pacific Plate and part of the North American Plate move in opposite directions. Such a boundary is called a transform boundary. Choice A is incorrect because a divergent boundary occurs where two plates spread apart. Choice B is incorrect because a convergent boundary occurs where two plates collide. Choice D is incorrect because it names a process, not a boundary. Subduction is a process in which a plate with oceanic crust sinks under another plate. 3. Choice A is correct. Fault-block mountains form when repeated earthquakes move large blocks of rock. Choice B is incorrect because volcanic mountains are produced by repeated volcanic eruptions. Choice C is incorrect because folded mountains are produced when rock crumples as plates collide. Choice D is incorrect because the eruption of magma where plates spread apart produces mid-ocean ridges in the sea and volcanic mountains on land. 4. Choice B is correct. The Coast Ranges are folded mountains, which formed from crumpling of the sea floor along the edge of the North American Plate at a time long ago when the Pacific Plate and North American Plate were colliding. Choice A is incorrect because it describes the process by which fault-block mountains are formed. Choice C is incorrect because the Coast Ranges do not contain active volcanoes. Choice D is incorrect because the Pacific Plate and North American Plate are not spreading apart. 5. Choice D is correct. The Central Valley is a downward fold in the North American Plate. Choice A is incorrect because the Central Valley is not part of the San Andreas Fault. Choices B and C are incorrect because they name the wrong plates. 6. Choice A is correct. The Cascade Range is a volcanic mountain range. Choices B and C are incorrect because the Cascades are volcanoes, not folded or fault-block mountains. Choice D is incorrect because the term subducted does not identify a type of mountain.
Plate Movement 6.1.g, Page 14 1. Choice B is correct. The epicenter is the point on Earth s surface directly above the focus, or underground point where the rocks first move in an earthquake. Choice A is incorrect because the focus is the underground point where the rocks first move in an earthquake. Choice C is incorrect because magnitude refers to the strength of an earthquake. Choice D is incorrect because seismic waves are the vibrations caused by an earthquake. 2. Choice A is correct. Scientists determine the epicenter of an earthquake by measuring the arrival time of seismic waves at a minimum of three recording locations. Choices B, C, and D are incorrect because the Richter scale, moment magnitude scale, and damage estimates are not used to determine an earthquake s epicenter. 3. Choice D is correct. All of the factors location of the focus and epicenter, magnitude, and type of soil and construction in a region influence the effects of an earthquake on a region. Choices A, B, and C are incorrect because they are incomplete and so not the best answer. 4. Choice D is correct. An earthquake with a higher magnitude and an epicenter closer to a city would cause more damage than an earthquake with a lower magnitude or one with an epicenter farther from a city. Choice A is incorrect because the magnitude is lower and the epicenter is farther away. Choice B is incorrect because the magnitude is lower. Choice C is incorrect because the epicenter is farther away. 5. Choice A is correct. An earthquake with a shallow focus would cause more damage than one with a deep focus, and brick houses would suffer more damage than wood-frame houses. Choice B is incorrect because an earthquake with a deep focus would cause less damage than one with a shallow focus. Choice C is incorrect because wood-frame houses are likely to suffer less damage than brick houses. Choice D is incorrect because a deep-focus earthquake would cause less damage, and wood-frame houses are likely to suffer less damage than brick houses.
Water Shapes the Landscape 6.2.a, Page 16 1. Choice C is correct. Water running downhill is the major natural force shaping the landscape. Choice A is incorrect because flooding is just one of the ways in which running water shapes landscape. Choice B is incorrect because weathering is just one of the processes by which water changes the landscape. Choice D is incorrect because volcanic activity does not shape as much of Earth s landscape as running water does. 2. Choice B is correct. The process by which rock is broken down into smaller particles without any chemical change is called mechanical weathering. Choices A and C are incorrect because erosion is the movement of particles, not the breakdown of rock, and because weathering is described as mechanical and chemical, but not erosion. Choice D is incorrect because chemical weathering does involve a chemical change. 3. Choice A is correct. A delta is the area of land that a river builds up as it empties into an ocean and drops much of its sediment. Choice B is incorrect because a canyon is narrow valley with steep walls cut by a stream. Choice C is incorrect because rivers do not build mountains at their mouths. Choice D is incorrect because a floodplain is a valley that fills with the floodwaters of a river. 4. Choice D is correct. The process by which water moves weathered particles from one place to another is called erosion. Choices A and B are incorrect because mechanical and chemical weathering do not involve the movement of particles. They are processes by which rock is broken down into smaller particles. Choice C is incorrect because delta formation is the buildup of land at the site where a river empties into an ocean. 5. Choice D is correct. Moving water creates eroded mountains, floodplains, and deltas. Choices A, B, and C are incorrect because they are incomplete and so are not the best answer.
Water Shapes the Landscape 6.2.a, Page 16 1. Choice C is correct. Water running downhill is the major natural force shaping the landscape. Choice A is incorrect because flooding is just one of the ways in which running water shapes landscape. Choice B is incorrect because weathering is just one of the processes by which water changes the landscape. Choice D is incorrect because volcanic activity does not shape as much of Earth s landscape as running water does. 2. Choice B is correct. The process by which rock is broken down into smaller particles without any chemical change is called mechanical weathering. Choices A and C are incorrect because erosion is the movement of particles, not the breakdown of rock, and because weathering is described as mechanical and chemical, but not erosion. Choice D is incorrect because chemical weathering does involve a chemical change. 3. Choice A is correct. A delta is the area of land that a river builds up as it empties into an ocean and drops much of its sediment. Choice B is incorrect because a canyon is narrow valley with steep walls cut by a stream. Choice C is incorrect because rivers do not build mountains at their mouths. Choice D is incorrect because a floodplain is a valley that fills with the floodwaters of a river. 4. Choice D is correct. The process by which water moves weathered particles from one place to another is called erosion. Choices A and B are incorrect because mechanical and chemical weathering do not involve the movement of particles. They are processes by which rock is broken down into smaller particles. Choice C is incorrect because delta formation is the buildup of land at the site where a river empties into an ocean. 5. Choice D is correct. Moving water creates eroded mountains, floodplains, and deltas. Choices A, B, and C are incorrect because they are incomplete and so are not the best answer.
Streams Are Dynamic Systems 6.2.b, Page 18 1. Choice C is correct. The word dynamic can mean full of energy, continually moving, or continually changing, and streams have all of these characteristics. Choice A is incorrect because streams do vary from season to season and from year to year. Choice B is incorrect because streams develop, evolve, and change over time, just like other aspects of the natural world. Choice D is incorrect because it has nothing to do with the meaning of the word dynamic. 2. Choice A is correct. A stream with a steep slope and high volume of water typically moves fast and causes much erosion. Choice B is incorrect because a stream with a steep slope and high volume of water causes much erosion, not little. Choice C is incorrect because this kind of stream can carry a lot of sediment. Choice D is incorrect because meanders typically develop in wide, flat valleys, not steep slopes. 3. Choice B is correct. An oxbow lake forms when a stream cuts a new channel segment that bypasses a meander. Choice A is incorrect because the deposition of sediment along an outside bank would not form an oxbow lake. Choice C is incorrect because a stream does not normally change directions and flow upstream, though such an event might occur momentarily during a strong earthquake. Choice D is incorrect because oxbow lakes typically form in wide, flat valleys, not in mountains. 4. Choice B is correct. Oxbow lakes typically form in the wide, flat valley of a floodplain. Choices A, C, and D are incorrect because oxbow lakes do not typically form in these kinds of locations. 5. Choice D is correct. Floods and changes in course are part of a stream s natural cycle. Choice A is incorrect because streams do not need to be dammed, even though people do construct dams to stop streams from flooding and changing course. Choice B is incorrect because floods and changing course are a natural occurrence. Choice C is incorrect because flooding and changing course are not abnormal for a stream.
Beaches Are Dynamic Systems 6.2.c, page 20 1. Choice C is correct. The word dynamic can mean continually moving and changing, and beaches are like streams in that they continually move and change. Choice A is incorrect because beaches do vary from year to year. Choice B is incorrect because beaches are not stable sites for homes because they are vulnerable to the erosive action of ocean waves and currents as well as storms. Choice D is incorrect because beaches do not always continue to grow. They can shrink as well as grow. 2. Choice A is correct. Streams carry sediment to oceans and drop some of it along the shores. Waves erode coastal land, producing sediment that mixes with the stream sediment. Choices B, C, and D are incorrect because they are not the primary sources of beach sand. 3. Choice D is correct. Waves and currents that move sediment along a shore build up beaches. Choices A and B are incorrect because flooding and strong winds do not produce most coastal beaches. Choice C is incorrect because strong storms do not pick up sediment from the bottom of the ocean. 4. Choice C is correct. Longshore drift is a zigzag movement of sand along a beach caused by angled waves. Choices A, B, and D are incorrect because longshore drift does not produce any of these effects. 5. Choice A is correct. Longshore drift and longshore currents move sand from one location to another, thus building up beaches at one site and eroding them at another. Choice B is incorrect because dunes do not result from longshore drift and longshore currents. They are built up by wind. Choices C and D are incorrect because longshore drift and longshore currents do not produce these results. 6. Choice B is correct. Differences in the composition of local sources of sediment might cause differences in the color of sand at different beaches. Choices A, C, and D are incorrect because these factors would not cause a significant difference in the color of sand at two beaches.
Natural Disasters Change Habitats 6.2.d, Page 22 1. Choice B is correct. Both earthquakes and volcanic eruptions often cause fires and landslides. Choices A, C, and D are incorrect because volcanic eruptions often cause changes in the weather, air pollution, and the formation of rich soil, but earthquakes typically do not. 2. Choice D is correct. Landslides, volcanic eruptions, and floods all result in human and wildlife habitats being carried away or buried. Choices A, B, and C are incorrect because they are incomplete and so not the best answer. 3. Choice C is correct. Volcanic eruptions and floods can both result in the formation of new, rich soil. Choice A is incorrect because floods do not build beautiful mountains. Choices B and D are incorrect because they are not positive effects, and tsunamis do not result from floods. 4. Choice B is correct. By studying the seismic waves produced by earthquakes, scientists learn about the structure of Earth s interior. Choices A, C, and D are incorrect because these events occur on Earth s surface and do not help scientists learn about Earth s interior. 5. Choice A is correct. Volcanic eruptions bring new rocks and minerals to Earth s surface. Choices B, C, and D are incorrect because floods and landslides occur on Earth s surface and so do not bring up new rocks and minerals. 6. Choice D is correct. Earthquakes, volcanic eruptions, landslides, and floods all play a role in shaping the landscape, changing habitats, and moving rocks and soil. Choices A, B, and C are incorrect because they are incomplete and so not the best answer.
Energy Is Transferred in Many Ways 6.3.a, page 24 1. Choice D is correct. The transfer of energy from a warmer object to a cooler object is called heat flow. Choice A is incorrect because an electromagnetic wave is the form in which energy from the Sun travels to Earth. Choice B is incorrect because mechanical energy is the energy that an object has as a result of its motion or position. Choice C is incorrect because a wave is a disturbance that carries energy from one place to another. 2. Choice C is correct. A wave is a disturbance that carries energy from one place to another. Choice A is incorrect because a moving object is not defined as a disturbance. Choice B is incorrect because mechanical energy is a form of energy, not a disturbance. Choice D is incorrect because heat flow is not a disturbance. 3. Choice B is correct. Sitting by a fire to warm one s body on a cold winter night is an example of heat flow. Choices A and C are incorrect because they are examples of the transfer of energy by a moving object. Choice D is incorrect because it is an example of the transfer of sound energy. 4. Choice A is correct. Light is carried by electromagnetic waves. Choice B is incorrect because sound is carried by sound waves. Choices C and D are incorrect because mechanical energy and chemical energy are not transferred by waves. 5. Choice D is correct. Kicking a soccer ball is an example of the transfer of energy by a moving object. Choice A is incorrect because it is an example of the transfer of energy by electromagnetic waves. Choice B is incorrect because it is an example of the transfer of energy by heat flow. Choice C is incorrect because it is an example of the transfer of energy by sound waves. 6. Choice A is correct. A wave carries energy, but not matter. Choices B and C are incorrect because a wave does not carry matter. Choice D is incorrect because a wave does carry energy.
Burning Fuel Produces Heat Energy 6.3.b, page 26 1. Choice A is correct. The energy that holds atoms together in molecules is called chemical energy. Choice B is incorrect because heat energy is the energy of particles in motion in an object. Choice C is incorrect because mechanical energy is the energy an object has because of its motion or position. Choice D is incorrect because light energy is a form of electromagnetic energy. 2. Choice B is correct. When fuel is burned, chemical energy is released and changes form, producing heat and light. Choice A is incorrect because burning fuel does not release mechanical energy. Choice C is incorrect because chemical energy is released and changes into heat energy. Choice D is incorrect because no energy is lost; the energy just changes form. 3. Choice D is correct. When expanding hot gases set a car s parts in motion, heat energy changes into mechanical energy. Choice A is incorrect because heat energy, not light energy, changes into mechanical energy. Choice B is incorrect because this is not an example of mechanical energy changing into chemical energy. Choice C is incorrect because this is not an example of chemical energy changing into heat energy. 4. Choice B is correct. The friction that results from applying a car s brakes causes mechanical energy to change into heat energy. Choices A, C, and D are incorrect because they do not identify the type of energy change involved. 5. Choice A is correct. Most of the chemical energy released by burning fuel in a car eventually becomes heat energy. Choices B, C, and D are incorrect because they name the wrong type of energy.
Heat Flow in Solids and Fluids 6.3.c, page 28 1. Choice D is correct. Conduction only occurs between two objects that are touching. Choice A is incorrect because conduction occurs in solids as well as fluids. Choice B is incorrect because conduction occurs in fluids as well as solids. Choice C is incorrect because both objects do not have to be heated for conduction to occur. One object must be warmer than the other. 2. Choice A is correct. When the particles in a warmer object collide with the particles in a cooler object, energy is transferred from the warmer object to the cooler object. Choice B is incorrect because heat energy moves from a warmer object to a cooler object, not the other way around. Choices C and D are incorrect because the warmer object loses energy while the cooler object gains it. 3. Choice B is correct. Most fluids expand when heated and become less dense and more buoyant. Choices A, C, and D are incorrect because each contain a wrong combination of density and buoyancy. 4. Choice C is correct. Convection occurs as hot water rises and cool water sinks. Choice A is incorrect because it applies to conduction, not convection. Choice B is incorrect because convection only occurs in fluids. Choice D is incorrect because cool water does not rise and hot water does not sink. 5. Choice C is correct. Convection only occurs in materials that can flow. Choice A is incorrect because convection occurs in gases as well as liquids. Choice B is incorrect because convection does not occur in solids. Choice D is incorrect because convection occurs in liquids as well as gases.
Transfer of Heat Energy by Radiation 6.3.d, page 30 1. Choice C is correct. Energy that travels in electromagnetic waves is called radiation. Choice A is incorrect because convection is the transfer of energy by the movement of a fluid. Choice B is incorrect because conduction is the transfer of energy between two objects that are in contact. Choice D is incorrect because charged particles have mass and are not purely electromagnetic waves. 2. Choice D is correct. Radiation can travel through empty space, while energy must travel through a medium in conduction and convection. Choice A is incorrect because all three processes occur in nature. Choice B is incorrect because conduction and convection also occur in more than one direction. Choice C is incorrect because all three processes transfer heat energy. 3. Choice A is correct. All objects give off radiation. Choices B, C, and D are incorrect because all objects, not just the Sun, Earth, or large objects, give off radiation. 4. Choice C is correct. When a person sits under a lamp, heat energy is transferred to the person by radiation. Choice A is incorrect because two objects must be in contact for conduction to occur. Choice B is incorrect because convection moves heat within fluids. Choice D is incorrect because conduction and convection do not occur in this situation. 5. Choice A is correct. Visible light and infrared radiation from the Sun are examples of types of radiation that provide useful energy. In fact, life on Earth depends on these types of radiation. Choice B is incorrect because these types of radiation are more beneficial than harmful. Choice C is incorrect because these types of radiation can be absorbed. Choice D is incorrect because these types of radiation have a huge effect on Earth.
The Energy of the Sun 6.4.a, page 32 1. Choice A is correct. The Sun is the main source of energy for both plants and animals. Choice B is incorrect because the water cycle is not the main source of energy for plants and animals, even though plants and animals both need water. Choice C is incorrect because soil is not the main source of energy for plants and animals, even though many plants get nutrients from soil. Choice D is incorrect because the ocean is not the main source of energy for plants and animals, even though many plants and animals live in the ocean. 2. Choice C is correct. Uneven heating of Earth s surface by the Sun causes differences in air pressure from place to place. Choices A and B are incorrect because the water cycle and ocean currents do not cause differences in air pressure from place to place. Choice D is incorrect because global winds are a result, not a cause, of differences in air pressure. 3. Choice B is correct. Wind results when air moves from areas of high pressure to areas of low pressure. Choice A is incorrect because air does not move from areas of low pressure to areas of high pressure. It does just the opposite. Choices C and D are incorrect because wind is a horizontal movement of air, not a vertical movement. 4. Choice D is correct. Global winds move warm air from the equator toward the north and south poles. Choice A is incorrect because cold air moves from the poles toward the equator. Choices B and C are incorrect because global winds do not move air across the equator. 5. Choice B is correct. Global winds moving across the water create surface currents in the ocean. Choices A, C, and D are incorrect because the water cycle, tropical storms, and changes in the weather are not the cause of surface currents in the ocean, even though they all have an effect on local movements of water. 6. Choice A is correct. Evaporation occurs when water is warmed by the Sun. Choices B and D are incorrect because they refer to condensation. Choice C is incorrect because it describes precipitation.
Solar Radiation 6.4.b, page 34 1. Choice B is correct. Solar energy reaches Earth as radiation, or in the form of electromagnetic waves. Choice A is incorrect because reflection is the redirection of radiation, not the way the Sun transmits radiation. Choice C is incorrect because conduction requires two objects to be in contact, and the Sun and Earth are not in contact. Choice D is incorrect because convection is the transfer of energy by the movement of fluids. 2. Choice D is correct. The Sun gives off radiation in the full range of the electromagnetic spectrum. Choices A, B, and C are incorrect because they name only some of the types of radiation that the Sun gives off. 3. Choice A is correct. Visible light passes through Earth s atmosphere. Choices B, C, and D are incorrect because Earth s atmosphere absorbs most of the energy from these types of radiation. 4. Choice A is correct. Visible light reaches Earth s surface in large amounts. Choices B, C, and D are incorrect because Earth s atmosphere absorbs most of the energy from these types of radiation. 5. Choice C is correct. Some of the solar radiation that reaches Earth s surface is reflected, and some of it is absorbed. Choice A is incorrect because not all of the solar radiation is reflected. Choice B is incorrect because not all of the solar radiation is absorbed. Choice D is incorrect because solar radiation does not pass through Earth.
Heat from Earth s Interior 6.4.c, page 36 1. Choice B is correct. Heat from Earth s interior moves toward the cooler crust because heat flows from a warmer object or material to a cooler object or material. Choice A is incorrect because the seasons do not affect the temperatures in Earth s interior. Choice C is incorrect because the crust is not hotter than Earth s interior. Choice D is incorrect because the heat does move beyond the mantle. 2. Choice C is correct. Heat from Earth s interior gets transferred to the surface primarily by convection. Choice A is incorrect because convection, not radiation, is the main process by which heat from Earth s interior gets transferred to the surface. Choice B is incorrect because rock is a poor conductor of heat. Choice D is incorrect because absorption is not a process by which heat gets transferred from Earth s interior to the surface. 3. Choice B is correct. Only a small amount of Earth s internal heat escapes to the surface. Choice A is incorrect because the amount of heat is small, not huge. Choice C is incorrect because the Sun provides almost all of the energy for processes at Earth s surface. Choice D is incorrect because the amount is not changing. 4. Choice D is correct. The Sun provides most of the heat for Earth s atmosphere and surface. Choices A, B, and C are incorrect because they all refer to heat that comes from Earth s interior, and that amount of heat is small compared with the heat supplied by the Sun. 5. Choice D is correct. Evidence of Earth s internal heat escaping to the surface can be seen in volcanoes. Choices A, B, and C are incorrect because the tropics, rainforests, and temperate regions do not display any special evidence of the escape of Earth s internal heat. Their heat comes primarily from the Sun. 6. Choice B is correct because soft, hot rock in the mantle is less dense and rises, and cooler rock is denser and sinks. Choice A is incorrect because convection currents occur in Earth s mantle, not in the cold, rigid rock of the crust. Choice C is incorrect because the soft, hot rock is less dense, so it rises. Choice D is incorrect because convection of rock occurs in Earth s mantle. Convection in the outer core involves the movement of molten metals. 7. Choice C is correct because differences in density cause convention-related movement. Choices A, B, and D are incorrect because differences in these factors do not cause convection-related movement.
Heat Circulation in the Atmosphere and the Oceans 6.4.d, page 38 1. Choice B is correct. Because of Earth s shape and tilt, the Sun heats the planet s surface unevenly. Choice A is incorrect because the Sun does not heat Earth s surface evenly. Choices C and D are incorrect because Earth s shape and tilt do not affect the speed at which the Sun heats Earth s surface. 2. Choice A is correct. Convection currents move cool polar air toward the equator and warm equatorial air toward the poles. Choices B and C are incorrect because these two factors do not produce air movement; they cause deflection of global winds. Choice D is incorrect because ocean currents do not move the air. 3. Choice B is correct. Surface currents in the ocean carry warm water from the equator toward the poles. Choice A is incorrect because the direction is reversed. Choices C and D are incorrect because surface currents do not move water between the northern and southern hemispheres. 4. Choice D is correct. Earth s rotation and the geography of the land cause global winds and surface ocean currents to be deflected. Choices A and B are incorrect because these two factors do not affect the speed of the winds and currents. Choice C is incorrect because the winds and currents do not reverse directions. 5. Choice C is correct. Convection currents are primarily responsible for the redistribution of heat energy in the atmosphere and oceans. Choice A and B are incorrect because these two factors do not cause global winds and surface ocean currents; they merely result in their deflection. Choice D is incorrect because radiation is not the main process by which heat energy from the Sun gets redistributed.
Changes in Weather 6.4.e, page 40 1. Choice A is correct. Heat energy is transferred to air that is in contact with warm areas of Earth s surface. Choice B is incorrect because air rises after it has been warmed. Choice C is incorrect because wind does not necessarily blow over surfaces whose temperature is higher than air temperature. Choice D is incorrect because an air mass can be warm or cool. 2. Choice B is correct. Wind blows from areas of high air pressure toward areas of low air pressure. Choice A is incorrect because differences in humidity do not necessarily cause differences in air pressure. Choice C is incorrect because differences in air pressure cause the movement of air masses and wind. Choice D is incorrect because winds cause the movement of clouds. 3. Choice C is correct. Humidity is a measure of the amount of water vapor in the air, and it increases when water evaporates into water vapor. Choice A is incorrect because humidity decreases when water vapor condenses. Choice B is incorrect because humidity decreases when water vapor freezes into ice. Choice D is incorrect because the movement of an air mass does not necessarily affect its humidity. 4. Choice D is correct. Clouds and precipitation are likely to form when moist air rises and cools. Choice A is incorrect because wind is the horizontal movement of air, and clouds and precipitation form in rising air. Choice B is incorrect because precipitation forms in air that has high humidity. Choice C is incorrect because water vapor condenses and forms precipitation when air cools. 5. Choice B is correct. Strong storms are likely to develop along a cold front that separates air masses that have a large difference in temperature and humidity. Choice A is incorrect because an air mass has similar conditions of temperature and humidity throughout. Choice C is incorrect because clouds and precipitation are unlikely to form in the sinking air of a high-pressure system. Choice D is incorrect because the condensation of water vapor does not necessarily lead to the formation of storms. 6. Choice D is correct. A change in climate requires a longterm change in weather conditions. Choice A is incorrect because a change in temperature during a day is part of weather, not climate. Choice B is incorrect because the passage of a front brings a short-term change in weather, not a long-term climate change. Choice C is incorrect because a single season of unusual weather is not a long enough time to be considered a change of climate.
Energy Transfer in Ecosystems 6.5.a, page 42 1. Choice A is correct. The Sun is the main source of energy for ecosystems, or all life on Earth. Choices B, C, and D are incorrect because they name substances that are important to life but are not the main source of energy for ecosystems. 2. Choice C is correct. In photosynthesis, a producer captures sunlight and stores it as chemical energy. Choice A is incorrect because it does not describe the process of photosynthesis, even though plants do take up nutrients from soil. Choice B is incorrect because plants change water and carbon dioxide, not oxygen, into glucose. Choice D is incorrect because it does not describe the process of photosynthesis. 3. Choice B is correct. In ecosystems, energy passes from organism to organism through food webs. Choices A, C, and D are incorrect because they name individual levels in a food web. 4. Choice D is correct. Consumers cannot make their own food. They must eat other organisms to get food. Choice A is incorrect because it is not a difference between consumers and producers. Choice B is incorrect because all organisms require energy. Choice C is incorrect because a consumer cannot make its own food. 5. Choice C is correct. The fish is a secondary consumer because it feeds on a primary consumer, which feeds on a producer. Choice A is incorrect because the plant is the producer. Choice B is incorrect because the insect is the primary consumer. Choice D is incorrect because a fish is not a photosynthetic organism. 6. Choice B is correct. At each successive feeding level in an ecosystem, the amount of available energy decreases because much of it is used up. Choice A is incorrect because the amount of available energy does not increase. Choice C is incorrect because the amount of available energy does not remain the same. Choice D is incorrect because the amount of available energy does not double.
Matter Cycles Through Ecosystems 6.5.b, page 44 1. Choice D is correct. Matter gets recycled. Choice A is incorrect because matter changes form in an ecosystem. Choice B is incorrect because matter moves through organisms in an ecosystem. Choice C is incorrect because the matter in an ecosystem does not get used up. 2. Choice A is correct. Matter moves from one organism to another as one organism consumes another. Choice B is incorrect because the production of food does not involve the transfer of matter from one organism to another. Choices C and D are incorrect because the processes of breathing or growing older do not directly involve the transfer of matter from one organism to another. 3. Choice A is correct. Because a cottontail rabbit eats only plants, it is an herbivore. Choice B is incorrect because a carnivore is an animal that eats other animals. Choice C is incorrect because an omnivore is an animal that eats both plants and animals. Choice D is incorrect because a decomposer breaks down dead plants and animals. 4. Choice B is correct. Because a great horned owl eats only animals, it is a carnivore. Choice A is incorrect because an herbivore is an animal that eats only plants. Choice C is incorrect because an omnivore is an animal that eats both plants and animals. Choice D is incorrect because a decomposer breaks down dead plants and animals. 5. Choice C is correct. Because a raccoon eats both plants and animals, it is an omnivore. Choice A is incorrect because an herbivore is an animal that eats only plants. Choice B is incorrect because a carnivore is an animal that eats other animals. Choice D is incorrect because a decomposer breaks down dead plants and animals. 6. Choice D is correct. A decomposer is an organism that breaks down dead plants and animals and returns matter to the environment. Choice A is incorrect because an herbivore is an animal that eats only plants. Choice B is incorrect because a carnivore is an animal that eats other animals. Choice C is incorrect because an omnivore is an animal that eats both plants and animals. 7. Choice C is correct. Bacteria are decomposers that return matter to soil or water, where it may be used again. Choices A and B are incorrect because herbivores don t return matter to the physical environment. Choice D is incorrect because it does not describe any type of relationship in a food web.
Categorizing Populations of Organisms 6.5.c, page 46 1. Choice B is correct. Timber rattlesnakes are predators because they kill and eat other animals. Choice A is incorrect because primary consumers eat plants. Choice C is incorrect because scavengers eat dead meat, and timber rattlesnakes capture their prey alive. Choice D is incorrect because decomposers feed on the remains of plants and animals. 2. Choice A is correct. Watercress is a plant, and plants are producers because they make their own food. Choice B is incorrect because a consumer gets its food from other organisms. Choice C is incorrect because a predator is an animal that kills and eats other animals. Choice D is incorrect because a scavenger feeds on dead animals. 3. Choice B is correct. Bison are primary consumers because they eat plants. Choice A is incorrect because producers make their own food. Choice C is incorrect because predators kill and eat other animals. Choice D is incorrect because scavengers eat dead animals. 4. Choice C is correct. Turkey vultures are scavengers because they eat dead animals. Choice A is incorrect because primary consumers eat live animals that eat plants. Choice B is incorrect because predators kill their prey. Choice D is incorrect because decomposers feed on plant and animal remains. 5. Choice D is correct. Common snapping turtles are primary consumers, secondary consumers, and predators because they eat water plants, and kill and eat other animals. Choices A, B, and C are incorrect because they are incomplete and so are not the best answer.
Niches in Biomes 6.5.d, page 48 1. Choice C is correct. An organism s niche is its ecological role in an ecosystem. Choice A is incorrect because an organism s method of reproducing is not its niche. Choice B is incorrect because an organism s place in a food web is only part of its niche, even though it is a major part. Choice D is incorrect because an organism s niche is not its living space. 2. Choice D is correct. A major part of an organism s niche is its place in a food web. Choice A is incorrect because physical appearance is not part of an organism s niche. Choice B is incorrect because abiotic factors are not part of an organism s niche. Choice C is incorrect because the biome is not part of an organism s niche, even though it determines the niches that are available. 3. Choice D is correct. A biome is a large region with a particular type of climate, plants, and animals. Choices A, B, and C are incorrect because they are incomplete and so are not the best answer. 4. Choice C is correct. On two deserts on two different continents, you would expect to find different species filling similar niches because the biomes are similar. Choice D is incorrect because you would expect the niches to be similar on similar biomes. Choice A is incorrect because you would not expect the species to be the same because they have evolved in geographic isolation. Choice B is incorrect because you would expect the species to be different, not the same, and the niches to be the same, not different. 5. Choice A is correct. Bison and zebras are examples of animals that play similar ecological roles in similar grassland biomes. Choice B is incorrect because these animals play the same ecological role that of grazers or primary consumers not different ones. Choice C is incorrect because bison and zebras live in similar biomes, not different ones. Choice D is incorrect because bison and zebras do not live in many different biomes
Carrying Capacity of an Ecosystem 6.5.e, page 50 1. Choice D is correct. The maximum number of individuals of a species that an ecosystem can support is called the carrying capacity. Choice A is incorrect because a pyramid of biomass is a diagram that shows the relationship between feeding level and mass of organisms. Choice B is incorrect because a biotic factor is a living part of an ecosystem. Choice C is incorrect because an abiotic factor is a nonliving part of an ecosystem. 2. Choice C is correct. Both abiotic and biotic factors affect the number and types of organisms that an ecosystem can support. Choices A, B, and D are incorrect because both abiotic and biotic factors influence the number and types of organisms an ecosystem can support, not one or the other and not neither. 3. Choice B is correct. At higher feeding levels, the number of organisms in an ecosystem generally decreases. Choices A, C, and D are incorrect because the number decreases. It does not increase, double, or remain constant. 4. Choice A is correct. Deer are lower in the food web, and so you would expect to find more deer than wolves. Choices B, C, and D are incorrect because you would expect to find more deer than wolves, not fewer and not the same number. 5. Choice A is correct. You would expect plants to be more numerous than herbivores, carnivores, or omnivores because plants are at the base of the food web. Choices B, C, and D are incorrect because herbivores, carnivores, and omnivores are at higher levels in the food web and so would be less numerous. 6. Choice A is correct because the migrating birds represent a living, or biotic, part of the ecosystem. Choice B is incorrect because building a new road is neither biotic nor abiotic. Choices C and D are incorrect because they represent abiotic parts of an ecosystem.
Comparing Energy Sources 6.6.a, page 52 1. Choice C is correct. Fossil fuels are useful sources of energy because they are easy to convert into useable forms and are easy to transport. Choice A is incorrect because fossil fuels are not unlimited in supply. Choice B is incorrect because fossil fuels do cause pollution. Choice D is incorrect because fossil fuels cannot be recycled. 2. Choice B is correct. Water power is renewable. Choice A is incorrect because dams are expensive to build. Choice C is incorrect because most suitable locations have been used. Choice D is incorrect because dams disrupt wildlife habitats and wildlife migration. 3. Choice B is correct. A major disadvantage of solar energy is that the systems for collecting and storing it are inefficient. Choice A is incorrect because solar energy is not expensive. Choice C is incorrect because solar energy does not cause water pollution. Choice D is incorrect because solar energy does not cause air pollution. 4. Choice A is correct. It would be difficult to greatly increase the use of hydroelectric power because there are few suitable locations for building dams. Choice B is incorrect because hydroelectric power does not cause pollution. Choice C is incorrect because the fuel for hydroelectric power is water, which is plentiful. Choice D is incorrect because hydroelectric power does not produce dangerous waste products. 5. Choice C is correct. Wind power can only be developed in areas with strong, steady winds. Choice A is incorrect because the development of wind power is not limited to mountainous areas. Choice B is incorrect because the development of wind power is not limited to areas near the ocean. Choice D is incorrect because the development of wind power is not limited to urban areas.