Chapter 4 Ecosystems and CommunitiesMULTIPLE CHOICE 1. The average year-after-year conditions of temperature and precipitation in a particular region are referred to as the region’s a. weather. c. ecosystem. b. latitude. d. climate. ANS: D STO: 12.E.4.a DIF: B REF: p. 87 OBJ: 4.1.1 2. All of the following factors contribute to Earth’s climate EXCEPT a. latitude. c. transport of heat. b. longitude. d. shape and elevation of landmasses. ANS: B STO: 12.E.4.a DIF: A REF: p. 87 OBJ: 4.1.1 3. Climate is a global factor that produces a. Earth’s unique ocean and atmosphere. b. the shape and elevation of landmasses. c. a wide range of environmental conditions that shapes communities. d. solar energy within the atmosphere. ANS: C STO: 12.E.4.a DIF: E REF: p. 87 OBJ: 4.1.1 4. Temperatures on Earth remain within a suitable range for life as we know it because of the a. unequal heating of Earth’s surface. b. loss of heat to space. c. radiation of sunlight back into the atmosphere. d. greenhouse effect. ANS: D STO: 12.E.4.a DIF: B 5. The loss of heat to space is slowed by a. radiation entering the atmosphere. b. atmospheric gases. ANS: B STO: 12.E.4.a DIF: A REF: p. 87 OBJ: 4.1.2 c. solar energy. d. the biosphere. REF: p. 88 OBJ: 4.1.2 6. The greenhouse effect is a. the result of an excess of carbon dioxide in the atmosphere. b. a natural phenomenon that maintains Earth’s temperature range. c. the result of the differences in the angle of the sun’s rays. d. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere. ANS: B STO: 12.E.4.a DIF: E REF: p. 87 OBJ: 4.1.2 7. Earth has three main climate zones because of the differences in latitude and, thus, a. amount of precipitation received. b. angle of heating. ANS: B STO: 12.E.4.a DIF: A 8. Cool air over the poles will a. rise. b. sink. ANS: B STO: 12.E.4.a DIF: B c. ocean currents. d. prevailing winds. REF: p. 88 OBJ: 4.1.3 c. absorb heat from the equator. d. flow parallel to Earth’s surface. REF: p. 89 OBJ: 4.1.3 9. The unequal heating of Earth’s surface a. drives wind and ocean currents. b. causes winds that transport heat throughout the biosphere. c. has important effects on Earth’s climate regions. d. all of the above ANS: D STO: 12.E.4.a DIF: A REF: p. 89 OBJ: 4.1.3 10. The tendency for warm air to rise and cool air to sink results in a. global wind patterns. c. unequal heat distribution. b. ocean upwelling. d. regional precipitation. ANS: A STO: 12.E.4.a DIF: B REF: p. 89 OBJ: 4.1.3 11. A mountain can affect climate by a. absorbing more solar energy at the peak than at the base of the mountain. b. causing precipitation to fall mostly on one side of the mountain. c. pushing a cool air mass back out over the ocean. d. interfering with air currents and affecting Earth’s rotation. ANS: B STO: 12.E.4.a DIF: E REF: p. 89 OBJ: 4.1.3 12. Why does Earth have three main climate zones? a. Warm air rises at the equator and cold air sinks over the poles causing an unequal distribution of heat over Earth. b. There are differences in latitude and, thus, the angle of heating from the sun. c. Continents and other landmasses physically interfere with global heat distribution. d. The Earth rotates and affects the major ocean currents. ANS: B STO: 12.E.4.a DIF: E REF: p. 88 OBJ: 4.1.3 13. Each of the following is an abiotic factor in the environment EXCEPT a. plant life. c. rainfall. b. soil type. d. temperature. ANS: A DIF: B STO: 12.B.4.a, 12.B.4.b REF: p. 90 OBJ: 4.2.1 14. Which is a biotic factor that affects the size of a population in a specific ecosystem? competition. d. increase their populations. c.4. An interaction in which one organism captures and feeds on another organism is called a.a. d. This behavior is probably due to a.B. a mountain lion may temporarily leave its usual hunting territory to drink from a farm pond. Several species of warblers can live in the same spruce tree ONLY because they a. occupy different niches within the tree.4. b. An organism’s niche is a.4.b REF: p. 90 OBJ: 4.b REF: p. During a long period when there is no rainfall. ANS: D DIF: B STO: 12. 92 OBJ: 4. Different species can share the same habitat. b.B.a. d. ANS: B DIF: E STO: 12. b. c.2 20.1 18.b REF: p.b REF: p. b. a full description of the place an organism lives.4.B.B.a.a. d.B.2. 12.B. b. 12. predation. all the physical and biological factors in the organism’s environment.2.B. c. . d. 12.4.4. eat less. 91 OBJ: 4. c.4.B. the change in an abiotic factor in its environment. 90 OBJ: 4. occupy different niches. eat different foods within the tree. the range of physical and biological conditions in which an organism lives and the way in which it uses those conditions. the range of temperatures that the organism needs to survive. b. c. d.2 19.1 16. 12. ANS: C DIF: A STO: 12. c. 12.b REF: p. mutualism. unless the species require different abiotic factors. can find different temperatures within the tree. the change in a biotic factor in its environment.4. No two species can occupy the same niche in the same habitat at the same time a. 92 OBJ: 4. its need to find different foods to eat.1 17.2. ANS: D DIF: A STO: 12. d.a.a. have different habitats within the tree. because of the competitive exclusion principle. because of the interactions that shape the ecosystem. average temperature of the ecosystem type of soil in the ecosystem number and kinds of predators in the ecosystem concentration of oxygen in the ecosystem ANS: C DIF: A STO: 12. 93 OBJ: 4. 12.2.4. but competition among them is reduced if they a.2. c. unless the species require different biotic factors.B. reproduce at different times. sybiosis.B.4.2.b REF: p.B.B.1 15.4. its need to find a new habitat.4.a. b. ANS: A DIF: B STO: 12. 4. 12. killing and eating the competitors of other species. a lava flow.2. b. b. ecological succession. a forest fire.B.2 22. ANS: B STO: 12. c. 94 OBJ: 4. climate change.B. Which factor(s) can influence continual change in an ecosystem? OBJ: 4. 12.3 .4.4.B. ANS: B STO: 12. 94 OBJ: 4. d.a.4. b. a severe storm.B.3 26.4. 12.B. population growth.B.B. c. Secondary succession begins on soil and primary succession begins on newly exposed surfaces. p.4. 93 OBJ: 4.4. ANS: B DIF: B STO: 12.b REF: p. b. 93 OBJ: 4. d.ANS: C DIF: E STO: 12.2. 95 27. 92. commensalism. The symbiotic relationship between a flower and the insect that feeds on its nectar is an example of a. living symbiotically with other species.2.a. 94.2 21. ANS: A DIF: A STO: 12. ANS: A DIF: E STO: 12. p. predation because the insect feeds on the flower. 92 OBJ: 4.2.B. d.4.B. Primary succession can begin after a.b DIF: B 25. c.a. farm land is abandoned. mutualism because the flower provides the insect with food and the insect pollinates the flower. A predator can increase the numbers of certain species in its habitat by a. c. Secondary succession begins with lichens and primary succession begins with trees. parasitism because the insect lives off the nectar from the flower.b REF: p.b DIF: B REF: p. The series of predictable changes that occurs in a community over time is called a. b. avoiding certain prey species.2 24.B. crowding out the species it does not eat. d. predation. Primary succession modifies the environment and secondary succession does not. What is one difference between primary and secondary succession? a. A symbiotic relationship in which both species benefit is a. mutualism. 12.2.4.B.4.2 23. commensalism because the insect does not harm the flower and the flower does not benefit from the relationship. Primary succession is slow and secondary succession is rapid. ANS: B STO: 12.3 c. 93 OBJ: 4. parasitism. climax community. REF: p.2.2. d.b REF: p. c. d. b.b DIF: A REF: p.4.b REF: p.a. 3. 98 OBJ: 4.4. Living organisms modify their environment a little at a time. little precipitation. Which of the following occurs during the ecological succession of an ecosystem? a. 95 OBJ: 4. 98 OBJ: 4. ANS: B DIF: B REF: p. tundra and desert d. different animals appearing at each stage c. temperate forest d.1 32.B. microclimates.B. d. An ecosystem reaches a final. Climate conditions in a small area that differ significantly from the climate of the surrounding area are called a. b. boreal forest and temperate woodland and shrubland OBJ: 4. another natural disturbance d. coniferous trees in a temperate forest.b DIF: A c. introduction of nonnative species d. 95 OBJ: 4. p.1 31. 94 OBJ: 4. tropical rain forest and temperate grassland b. Which of the following can influence the climate in a small area within a biome? a.3.3. biomes.3 28. d.b DIF: E REF: p. a mountain range capped with ice. the average temperature and precipitation b. the latitude of the biome c.b DIF: E REF: p.3 30. tundra b.3 29. desert c. An example of a place with a microclimate is a.3. colonization of surfaces by lichens b.2. ANS: C STO: 12.1 33.2 . Which is a factor that could interrupt the progress of succession? a.a. d. long-term climate changes ANS: D STO: 12. Which two biomes have the least amount of precipitation? a. a forested park in a desert city. 94. c. b. ANS: B DIF: A REF: p.B.4. ecosystems. b. Parts of communities split off to form new communities.2. long-term fluctuations in climate ANS: C STO: 12. the greenhouse effect ANS: C DIF: E REF: p.4. unchanging stage. all of the above REF: p. tropical savanna and tropical dry forest c. c.2. Changes occur that are caused by organisms outside the ecosystem. natural features. and permafrost? a. an orchid growing in a rain forest. natural features such as a lake d. 104 34. further disturbances b. 99 OBJ: 4. c. Which biome is characterized by very low temperatures. tropical dry forest ANS: C DIF: B REF: p. estuaries. 107 OBJ: 4. hooks c. organisms that live there. temperature of the water. 103 OBJ: 4.4. A biome is identified by its particular set of abiotic factors and its a. Wetlands are important breeding grounds for migratory birds.4. marshes. moose ANS: A DIF: E REF: p. 107 OBJ: 4. 106 OBJ: 4. characteristic ecological community. amount of salts. d. c. ANS: B DIF: E REF: p. Water may be present near the surface of the soil for part of the year. p. The chemistry of aquatic ecosystems is determined by the a. d. Which one of the following statements is NOT true of freshwater wetlands? a. specific geographical location.ANS: C OBJ: 4. tentacles d. d. b. d. d. Which is one way a wetland ecosystem differs from a standing-water ecosystem? a. depth and flow of the water. Water circulates in a standing-water ecosystem but not in a wetland. suckers ANS: B DIF: A REF: p. b. amount of rainfall the water receives. and is home to a variety of vegetation. such as coniferous trees. fertile soils. and swamps. and ferns? a.2 42.2 41. iguana b.2 36. c. whitetail deer c. wetlands. c. ANS: A DIF: A REF: p. and oxygen dissolved in the water. flowing-water ecosystems. . warm summers. b. flowering shrubs. c. 101.2 37. Aquatic ecosystems are classified by all of the following EXCEPT a. 98 OBJ: 4. average precipitation and temperature. REF: p. Which animal would be found in the biome that has cold to moderate winters. ANS: C DIF: B REF: p. 106 OBJ: 4.1 39. 106 OBJ: 4. Freshwater wetlands include bogs. polar bear d. chemistry of the water.3. broadleaf deciduous trees. streamlined bodies b. but standing-water ecosystems are not. standing-water ecosystems.1 c.4. b. b. ANS: C DIF: B REF: p. the number of other organisms present in the water.4. b.2 DIF: A REF: p. 104 35.1 38.3. Wetlands are nesting areas for birds. nutrients. biotic and abiotic factors in the water.4.3. ANS: C DIF: E 40. Ponds and lakes are a. Which is NOT an adaptation that organisms have for living in flowing water? a. distance from the equator. The water in freshwater wetlands is always brackish. The photic zone a.a REF: p.3 44. d. ANS: B DIF: B REF: p. Earth’s natural “insulating blanket” is the biosphere. atmosphere DIF: E REF: p. is deep. _________________________ ANS: F. Most of the photosynthetic activity on Earth occurs in the open ocean within the photic zone.2 STO: 12. _________________________ ANS: T OBJ: 4. battering waves. 107 OBJ: 4. Water does not always cover a wetland as it does a standing-water ecosystem. b.4.1. The amount.1. c.E. Which of the following statements is NOT true about the open ocean? a. and duration of sunlight striking Earth vary with latitude.4. 112 OBJ: 4.3 45. and permanently dark. extends to the bottom of the open ocean.4. Which organism lives where it is sometimes submerged and routinely exposed to air. 88 . ANS: C DIF: E REF: p. dolphin b.E.4. but standing-water ecosystems are fresh.4.4.a 3. 87 OBJ: 4. The greenhouse effect occurs when carbon dioxide and other gases prevent heat energy from leaving the atmosphere. The open ocean has very low levels of nutrients.a 2. and water vapor trap light energy. b.2 43. heat. d. Carbon dioxide. d.3 DIF: A STO: 12. The open ocean begins at the low-tide mark and extends to the end of the continental shelf. and strong currents? a.1.4. _________________________ ANS: F. intensity.3 MODIFIED TRUE/FALSE 1. Wetlands are salty. cold.c. heat DIF: A REF: p.E.a 4. Organisms in the deep ocean are exposed to frigid temperatures and total darkness. 87 OBJ: 4. 110 OBJ: 4.4.2 DIF: B REF: p. ANS: C DIF: A REF: p.1. methane. is where chemosynthetic bacteria are the producers. 109 OBJ: 4. _________________________ ANS: T OBJ: 4. tube worm d. whale ANS: A DIF: E REF: p. extends to a depth of about 200 meters.E. c. sea star c.2 STO: 12. 87 STO: 12. 3. light DIF: A REF: p. 100 OBJ: 4. 101 OBJ: 4.5. ______________________________ ANS: F.4.4.a.3 DIF: B REF: p. A symbiotic relationship between organisms in which one species benefits and the other is neither helped nor harmed is mutualism. a microclimate DIF: E REF: p.2. The single-cell algae that grow in lakes and ponds are zooplankton. 104 9. dry DIF: B REF: p. perennial grasses and herds of grazing herbivores are inhabitants of the desert biome.3. _________________________ ANS: F.B.2 DIF: E REF: p. _________________________ ANS: T OBJ: 4.2 11. commensalism DIF: B REF: p. Tall. 12. 94 STO: 12. phytoplankton . The temperate forest biome is typically warmer and has more rainfall than the boreal forest biome. tropical savanna DIF: A REF: p. Palm trees and shrubs around a small pool of water in the middle of a barren desert is an example of an ecosystem. 98 OBJ: 4.B.4. ____________________ ANS: F. The tropical rain forest is characterized by a wet season and a dry season. 103.2 10.1 8.1 12. An existing community is gradually replaced by another community in an ecological succession. _________________________ ANS: F. 93 OBJ: 4. ______________________________ ANS: F.2 STO: 12.b 6. The depth of the water in an aquatic ecosystem determines the amount of oxygen that living things receive there. _________________________ ANS: T OBJ: 4.3.2.4. p. ______________________________ ANS: F.B.3. 106 OBJ: 4.b 7. distance from shore. Wetlands DIF: E REF: p. The zones of the marine biome are determined by light penetration.E.a 2. 87 OBJ: 4. _________________________ ANS: F.4. ANS: climate DIF: A REF: p. 87 OBJ: 4.1.E. 87 OBJ: 4. and depth.1 STO: 12. 107 OBJ: 4. The coastal ocean zone and estuaries are alike in that both are important as breeding and nesting areas for birds.a . the water flow typically changes from a turbulent current to slow meanders.1. _________________________ ANS: T OBJ: 4. p.1.2 STO: 12.a 4. As a flowing-water ecosystem travels downhill from its origin.1 STO: 12.1 STO: 12. Atmospheric gases that trap heat inside Earth’s atmosphere are called ____________________ gases. ANS: greenhouse DIF: B REF: p. 109 15. Weather differs from ____________________ in that weather can change on a daily basis and is not considered a description of year-to-year conditions of temperature and precipitation.a 3. 107.3 DIF: A REF: p. 87 OBJ: 4.1.DIF: B REF: p. ANS: sunlight DIF: B REF: p.4. 106 14.2 COMPLETION 1. 108 OBJ: 4. _________________________ ANS: T OBJ: 4.4.4.4.2 DIF: E REF: p. ANS: weather DIF: E REF: p.4.4.E.4. The energy of incoming ____________________ drives Earth’s weather and helps to determine climate.2 13. Average year-after-year conditions are to climate as day-to-day atmospheric conditions are to _________________.E. Organisms within an ecosystem are ____________________ factors in that ecosystem. 12.4.2.b 8.a.5°N.4.1 STO: 12.b 9.3 STO: 12.4. A small city park that is sunnier and windier than the climate of the surrounding areas has its own _________________________. The new plants use up water and nutrients needed by the previous plants.a 6.E. 23.4.5°S DIF: A REF: p. 98 OBJ: 4.E.a 7. ANS: 66.B.1.5°N DIF: A REF: p. The disappearance of the first plants is due to ______________________________. ANS: 23.B. ANS: biotic DIF: B REF: p. some plants growing in an area are crowded out by other plants. According to Figure 4–1.1. ANS: microclimate DIF: B REF: p. 90 OBJ: 4. 88 OBJ: 4.B. 12. the north polar zone lies above ____________________ latitude.2.3 STO: 12.3.4.Figure 4–1 5. As shown in Figure 4–1. ANS: competitive exclusion DIF: E REF: p. 88 OBJ: 4. the climate zone that receives the most direct sunlight throughout the year lies between ____________________ and ____________________ latitudes.2 STO: 12.a. 92 OBJ: 4. Over time.4.1 .B. B.2 11.4. Photosynthesis is limited to the well-lit upper layer of the ocean. A swamp is different from a lake as a freshwater ecosystem because a swamp is a ____________________ ecosystem.a. The abiotic factor used to determine the climate of an area that has the least effect on aquatic ecosystems is ____________________.4. 107 OBJ: 4.b SHORT ANSWER 1. ANS: rainfall precipitation DIF: E REF: p.2 14. ANS: photic DIF: B REF: p.a. 12. and oxygen in the water.3 STO: 12.B. nutrients. and the amount of precipitation that results. 12.4. 109 OBJ: 4.4. moist air from the Pacific Ocean and giant redwood trees characterize the ______________________________. ANS: chemistry DIF: A REF: p.4. the shape and elevation of landmasses . which scientists refer to as the ____________________ zone.4. ANS: wetland DIF: A REF: p. Coral reefs cannot survive more than 40 meters below the ocean surface because of their ________________________ relationship with algae. 103 OBJ: 4. 106 OBJ: 4. Mild. p.1 12.4. List five factors that contribute to global climate patterns. 93.10.b 13. ANS: Five factors are: the trapping of heat by the atmosphere. 106 OBJ: 4.3.4. An aquatic environment’s water ____________________ refers to the amount of dissolved salts. the transport of heat by winds and ocean currents.3 15. latitude. 90. ANS: symbiotic DIF: E REF: p.B. ANS: northwestern coniferous forest DIF: E REF: p. p.4.1 STO: 12.B. 109 OBJ: 4. 1.1. Atmospheric gases trap heat energy inside Earth’s atmosphere.E. explain why average temperatures decrease with increasing distance from the equator. p.2 STO: 12. ANS: The sun’s rays strike Earth at increasingly lower angles with increasing distance from the equator. 88 OBJ: 4. 87 OBJ: 4.E. Using Figure 4–1. 87. 88. describe a climate you might find at 10°N latitude. and water vapor. thus providing less and less direct sunlight.4. What are greenhouse gases? ANS: Greenhouse gases are atmospheric gases.3 STO: 12.1. How are atmospheric gases like the glass in a greenhouse? ANS: Glass traps heat energy inside the greenhouse.E.2 STO: 12.a 3. p. methane. 89 OBJ: 4. 87 OBJ: 4. because this location is in the tropical zone.1. DIF: B REF: p. rainy climate. that trap heat energy.4. DIF: B REF: p.DIF: A STO: 12. such as carbon dioxide.4. Using Figure 4–1.1 2. . ANS: The climate at 10°N latitude is most likely a hot. DIF: B REF: p.a Figure 4–1 4.a REF: p.4.a 5.E. DIF: A REF: p.E.B. light. in commensalism.DIF: A REF: p. Deserts vary greatly depending on elevation and latitude.1 STO: 12. ANS: Biotic factors may include: plants the rabbit eats. 90. What is an ecological resource? ANS: An ecological resource is any necessity of life for an organism. Explain why plants do not participate in the succession of a whale-fall community as they do in landecosystem succession.4.3 STO: 12. DIF: B REF: p. What characteristic do all deserts share? .4. such as water.B.4. pioneer plants help rocks to break up in the process of soil formation and contribute organic material to the forming soil in which plants can grow. rainfall.b 8.2. DIF: E REF: p. 12.B. ANS: Whale-fall succession takes place on the deep. and other competitive species.B. only one species benefits whereas the other is neither helped nor harmed.a 6.3 STO: 12.2. or space. List three biotic and three abiotic factors that determine the survival of a rabbit in a temperate forest. Describe an important role that pioneer species play in primary succession.B.4. 92 OBJ: 4. 12. 88 OBJ: 4. thus.1.a. Food is part of the biological conditions that a bullfrog uses.4.b 11.1 STO: 12. permanently dark ocean floor where there is no light for photosynthesis. 12. predators that eat the rabbit.a. ANS: In primary succession.4.b 9.4. Explain why the food that a bullfrog eats is considered a part of its niche.B. 103 OBJ: 4.2.4.b 7. and space. both species benefit from the relationship. 93 OBJ: 4.a. no plants can grow.B. nutrients.B. DIF: A REF: p. In mutualism. 91 OBJ: 4. 12.2.b 10.a. food.2 STO: 12.4. How is mutualism similar to and different from commensalism? ANS: They are both symbiotic relationships.2.B. DIF: E REF: p.B. p. ANS: A niche includes all of the physical and biological conditions in which an organism lives and how the organism uses those conditions.3 STO: 12.b 12. 94 OBJ: 4.2 STO: 12. DIF: A REF: p.4.4. Abiotic factors may include: temperature.2. 96 OBJ: 4. 109 OBJ: 4. 106.3.1 14.2 15.4. flow. 107 OBJ: 4.4.3 OTHER USING SCIENCE SKILLS Average Rainfall and Temperature of Earth’s Biomes Biome Average Yearly Rainfall Tropical rain forest 400 cm Tropical dry forest 250–300 cm Temperate forest 75–125 cm Boreal forest 35–75 cm Tropical savanna 150 cm Desert Less than 25 cm Average Temperature Daytime: 34ºC Nighttime: 20ºC Dry season: 32ºC Wet season: 20ºC Summer: 28ºC Winter: 6ºC Summer: 14ºC Winter: -10ºC Dry season: 34ºC Wet season: 16ºC Summer: 38ºC Winter: 7ºC Climate Zone Tropical Tropical Mostly temperate Mostly temperate Mostly tropical Tropical and temperate . What criteria are used for determining ocean zones? ANS: The vertical ocean zones are determined by the distance from shore and the depth of the water. The horizontal zones are determined by how far light penetrates the water. Why are hooks and suckers not typically found in organisms inhabiting standing-water ecosystems? ANS: Hooks and suckers are adaptations for holding on in moving water and are common only in organisms that inhabit flowing-water ecosystems.2 13.ANS: A desert biome is defined as having less than 25 cm of annual rainfall. 106 OBJ: 4. p. 101 OBJ: 4.4. and chemistry of the overlying water. DIF: B REF: p. DIF: E REF: p. DIF: E REF: p. DIF: E REF: p. What are the three main factors that govern aquatic ecosystems? ANS: Aquatic ecosystems are determined by the depth. desert. resulting in a colder climate than the tropical rain forest. The tundra receives sunlight at a much lower angle. DIF: B OBJ: 4.1 STO: 12. temperate woodland and shrubland.1. DIF: B REF: p. Using Tables and Graphs Which biomes listed in Figure 4–2 include areas that have an average yearly rainfall of less than 75 cm? Which biomes include areas that have an average yearly rainfall of more than 200 cm? ANS: Biomes that have less than 75 cm of yearly rainfall include: boreal forest.1. and tundra. compare the average daytime temperature of the tropical rain forest with the average summer temperature of the tundra.4. Comparing and Contrasting In Figure 4–2.1.3. Calculating What is the highest average temperature shown in Figure 4–2? The lowest average temperature? How many degrees of temperature are there between the highest and the lowest temperatures? ANS: highest temperature = 38°C. temperate grassland. Analyzing Data Which two biomes shown in Figure 4–2 have seasons determined by the amount of precipitation they receive at different times of the year? .2 5. How can you account for the difference? ANS: The tropical rain forest has an average daytime temperature of 34°C. Using Tables and Graphs Which climate zone listed in Figure 4–2 includes the most biomes? ANS: temperate zone DIF: B OBJ: 4.a 2.2 3. The difference is that the tropical rain forest receives almost direct sunlight all year long.E. There are 64 degrees between the highest and lowest temperatures. The tundra has an average summer temperature of 12°C.Temperate grassland 25–75 cm Tropical woodland and scrubland Less than 50 cm Tundra 30–50 cm Summer: 30ºC Winter: 0ºC Summer: 20ºC Winter: 10ºC Temperate Summer: 12ºC Winter: -26ºC Temperate and polar Temperate Figure 4–2 1.3 4. lowest temperature = –26°C. Biomes that have more than 200 cm of yearly rainfall include: tropical rain forest and tropical dry forest. (38 Celsius degrees above zero + 26 Celsius degrees below zero) DIF: B OBJ: 4. 88 OBJ: 4. Interpreting Graphics The boreal forest and river valley depicted in Figure 4–3 were swept by fire 20 years ago. 100. 101 OBJ: 4.a. Applying Concepts Describe some of the biotic and abiotic factors you might find at point A and in region B of Figure 4–3. and the animals in the water would have adaptations to keep themselves from being swept away. 90 OBJ: 4. DIF: A REF: p.B. p. The water is most likely turbulent and cold.4.2. ANS: Point A is the origin of this flowing-water ecosystem. 12.ANS: The tropical dry forest and the tropical savanna each have a wet season and a dry season. The forests on the hills on each side of the river valley were cut down. There would be little plant life in the water due to the turbulence. Region B would have swiftly moving water.3.b 7.1 STO: 12.4. ANS: .2 USING SCIENCE SKILLS Figure 4–3 6. DIF: B REF: p. which would be turbulent where it goes over the waterfall.B. Does this illustration show an earlier or later stage of succession? Which kind of succession has taken place? Explain what will happen in this ecosystem if there are no more disturbances. The hills show a growth of shrubs and a few small trees. it would eventually have the ecological characteristics of a land biome. the water is moving slowly and meandering across the land. The river also carries nutrient-rich sediments down to regions D and E from higher up the mountain. 106. 94. DIF: A REF: p. the sediments carried by the water have formed a marsh where the flow is moving gradually toward a lake. ANS: A lake would form above the dam. ANS: Regions D and E would contain more nutrients because the water is moving very slowly and more plants can grow. The dry land would then undergo secondary succession. Predict what might happen to this flowing-water ecosystem in a boreal forest biome if a dam were built on the river in region C. an ecologically characteristic boreal forest will grow if there are no more disturbances.3. 104 OBJ: 4.2. 107 OBJ: 4. They are alike in that they are both part of the same aquatic ecosystem. Eventually. p. The regions are different in that the water is moving faster in region D than in region E. 106. DIF: A REF: p. 95. Inferring Which regions of the river in Figure 4–3 contain more nutrients than the other regions? Explain. In region E.B. and because of the climate and latitude. 106. 107 OBJ: 4.4. It can support algae and bacteria and many more organisms than farther up the mountain where they would be washed away in the current.2 USING SCIENCE SKILLS Some Organisms of the Marine Biome Intertidal Zone Oceanic Zone Coastal Ocean Zone Photic Zone Aphotic Zone Algae Coral Diving birds Angler fish Anemone Dolphins Dolphins Deep-sea octopus Barnacles Jellyfish Herring Hatchet fish . DIF: A STO: 12.4. the marsh below the dam might dry up. p.2 9. This indicates a later stage of secondary succession. ANS: Sample answer: In region D.3 8. p. a boreal forest.b REF: p. Describe the physical characteristics of each region. and region E likely has more numbers and kinds of organisms. With a reduced flow of water. Predicting Examine Figure 4–3.4. p. p. DIF: A STO: 12. p.1 10. 107 OBJ: 4. p.B.4. Comparing and Contrasting Compare and contrast region E in Figure 4–3 with region D. 95. creating a standing-water ecosystem. 104.b REF: p. 4. ANS: At high tide.b 12. sea water is an abiotic factor because the intertidal organisms are submerged.4.Birds: Kelp Jellyfish Krill Gull Lobsters Marlin Lantern fish Herons Otters Penguins Sea cucumbers Plovers Plankton Plankton Sponges Terns Sailfish Salmon Squids Clams Sea stars Sea snakes Hydrothermal Vent Crustaceans Sea urchins Sea turtles Chemosynthetic Mollusks Seals Sharks Mussels Sharks Shrimp Clams Sea urchins Small fish Swordfish Crabs and other Seaweed Snails Tuna Snails Whales Whales bacteria crustaceans Tube worms Figure 4–4 11.B. Comparing and Contrasting Contrast the abiotic factors at high tide with those at low tide for the organisms in the intertidal zone in Figure 4–4. sunlight. heat. ANS: .B. 90. and strong currents. battering waves.1 STO: 12. 12.a. DIF: E REF: p. p. Inferring From the table in Figure 4–4.2. At low tide. select at least three organisms from the coastal ocean zone and describe how they might interact. 110 OBJ: 4. the abiotic factors are exposure to air. DIF: E REF: p. p. describe energy availability in the open ocean at a depth of 6000 meters and at 150 meters.1. chemosynthetic bacteria are the producers. Some species of clams. the zones where it is happening. Like air currents.3 ESSAY 1. Whale-fall succession supports several communities over time. Other benthos feed on dead organic materials that drift down from the surface.b OBJ: 4.4. DIF: E REF: p. At 150 meters. Meanwhile. 110 STO: 12. Generally. 110 OBJ: 4.B.4. 12. the water flow creates ocean currents.4. which of the organisms from any column can also be listed in the photic zone column? Justify your answer. 109.2 13.1 STO: 12. sea urchins.4. only those organisms listed in the aphotic zone and chemosynthetic bacteria would not be found in the photic zone. Also. p. 109.2. ocean currents transport heat energy within the biosphere. and increases diversity in the whalefall area. providing energy for organisms that inhabit the area. Identify the event. in the area of the hydrothermal vent. Interpreting Graphics Using Figure 4–4.3 STO: 12. ANS: All of the organisms listed in the intertidal zone can be listed in the photic zone column.Sample answer: Kelp and the algae in plankton are producers and are food for many of the organisms in the coastal ocean zone.b 14.a. crabs.4. Analyzing Data From the table in Figure 4–4. Explain how ocean currents originate and affect Earth’s climates. thus affecting the weather and climate of nearby landmasses. Large fishes such as sailfish and sharks. ANS: At 6000 meters. compete for resources on the ocean floor. Using Models Figure 4–4 shows an event that is taking place at about 2000 meters on the open ocean. ANS: Cold water near the poles sinks and then flows parallel to the ocean bottom. and its importance to the marine biome. Surface ocean currents warm or cool the air above them. Complex food webs exist in this upper area of the ocean. ANS: Whale-fall succession is occurring at 2000 meters in the aphotic. sea stars. p. surface water is moved by winds. and open ocean zones.4. DIF: E REF: p.2. 93. 89 OBJ: 4.B. and lobsters. algae are the producers because this is within the photic zone. eat the small fishes. all of the organisms listed in the coastal ocean zone can be listed in the photic zone because the coastal ocean zone is almost always in the photic zone.E. p. DIF: E REF: p. p. DIF: A REF: p. In both cases.B.1 15. 112 OBJ: 4. 92. eventually rising again in warmer regions through a process called upwelling. 96.a . benthic. such as snails. and tube worms could also be listed in the photic zone. and mammals such as dolphins. 109 OBJ: 4. This zone is always in the photic zone. Benthos. 12. ticks. In parasitism. rise above freezing temperatures and would not support life as we know it now. Earth’s greenhouse effect prevents this from happening by trapping heat energy. This effect provides a natural insulating blanket around Earth and maintains its temperature range.4.2 STO: 12.E. mosses. Describe the greenhouse effect and explain how it maintains Earth’s temperature range. p. do not allow heat energy to pass out of the atmosphere. 88 OBJ: 4. 88. methane.E. 87. This natural situation in which heat is retained by these greenhouse gases is called the greenhouse effect. DIF: A REF: p. Describe the stages of primary succession in land environments.2 STO: 12.B. Atmospheric gases. In the temperate zone. Give examples of each. ANS: Because Earth is a sphere that is tilted on its axis. DIF: E STO: 12.a 3. and lice are examples of parasites that live on the bodies of mammals. including lichens. the sun’s rays are most direct so the climate is almost always warm. and water vapor. In commensalism.1. DIF: A REF: p. grasses. 101 OBJ: 4. the climate ranges from hot to cold depending on the season. Predict how the tropical rain forest and desert biomes would change if Earth were 30 degrees Celsius cooler than it is today. The host can be damaged but is usually not killed. or other substances.b 6. p. different parts of its surface receive varying amounts of solar radiation.a. flowers depend on certain insects to pollinate them.B. At the equator in the tropical zone. What phenomenon keeps this from happening? ANS: The tropical rain forest biome would seldom.a 5. 87. Desert biomes would only briefly rise above freezing temperatures during the summer and would probably more closely resemble the tundra biome as it is today. DIF: E REF: p.E.2. The polar zones receive the sun’s rays at the lowest angle and are always cold.4. pollen. ANS: Solar energy has an important effect on the temperature of the atmosphere. and parasitism. 93 OBJ: 4. and trees. shrubs.4. both species benefit from the relationship. p. such as carbon dioxide.1. Earth has three main climate zones. if ever. 100.2. one member benefits by obtaining all its nutritional needs from the host.4. but the whale is not affected. The flowers provide the insects with food in the form of nectar. one member of the association benefits and the other is neither helped nor harmed. Describe Earth’s main climate zones and explain how latitude affects these climate zones. As a result of differences in latitude and thus the angle of heating. Barnacles attached to the skin of whales benefit from food particles in the water moving past the swimming whale.a REF: p. . For example. ANS: The three main classes of symbiotic relationships are mutualism. Climates become generally cooler and drier with increasing distance from the equator.1. In mutualism. p. which keeps the planet warm and maintains Earth’s present temperature range. 88 OBJ: 4.3 STO: 12.2 4.4. Fleas. commensalism. Name and define the three main classes of symbiotic relationships. An example of a microclimate is the redwood forests on parts of California’s northern coast. Over several years. beavers. Migratory birds. Some areas a short distance inland from these forests are desertlike. and other natural features can influence the climate in a small area within a biome. and short grasses due to the short growing season and the long. ANS: Mountains. DIF: E REF: p. The tundra is characterized by ground-hugging plants such as lichens. such as fish with streamlined bodies and catfish with suckers to anchor themselves to the rocks.B.ANS: Primary succession occurs on newly exposed surfaces. inhabited by cactuses and other drought-resistant plants. List the six main zones of the marine biome.2 9. lakes. Explain how these zones are differentiated. and small rodents are some of the animals that inhabit the tundra. thrive there. plants are able to establish themselves. Cold temperatures. mosses. What is a microclimate? Give an example. The climate within such a small area often differs significantly from the climate of the surrounding area and is called a microclimate. The first organisms to appear are plantlike lichens that colonize the newly formed volcanic surfaces. Where sediments build up. high winds. Organisms with adaptations for living in swift water. it picks up sediments.1 8. 94 OBJ: 4. Explain why there are no tall trees in the tundra biome.b 7.3. DIF: A REF: p. DIF: E REF: p. cold.2 10. and permafrost limit plant height. dark winters.3. 104 OBJ: 4. various species of plants including mosses and grasses establish themselves among the rocks and then take root in the thin layer of soil. What are some of the biotic and abiotic phenomena that exist in the tundra? ANS: Summers are not long enough or warm enough to thaw the soil so that tall plants like trees can grow roots. A characteristic ecological community may eventually dominate the area.3 STO: 12. and river otters. oceans. such as a fresh lava flow that destroys the previous ecosystem.4. Eventually. The water flows more slowly downstream and the plants and animals grow more diverse to include turtles.2. forests. 98 OBJ: 4. ANS: A freshwater ecosystem is turbulent where it springs from its source so few plants can become established. tree seedlings and shrubs sprout among the plant community. DIF: E REF: p. ANS: .4. Why does a flowing-water ecosystem often support little plant life at its source? Describe how the ecosystem changes to support organisms as it flows. As the water flows. caribou. 106 OBJ: 4. DIF: A REF: p. p. which is the area most affected by tides. The vertical zones include the intertidal zone. the open ocean.3 . This is the largest marine zone.A. Another somewhat horizontal zone is the benthic zone.The main zones of the marine biome are the photic zone. the aphotic zone.4. 110. The open ocean begins at the edge of the continental shelf and extends outward. This zone extends along the ocean floor from the coastal ocean through the ocean zones. the coastal ocean. 13.A. p.4.c. which is the well-lit upper layer where photosynthesis takes place. The horizontal zones include the photic zone. Below the photic zone is the aphotic zone. 109. covering more than 90 percent of the surface area of the world’s oceans.b OBJ: 4. The coastal ocean extends from the low-tide mark to the end of the continental shelf. and the benthic zone.4. which is permanently dark. the intertidal zone. 111 STO: 11.