ch 52 mastering bio
limnetic zone
a zone of open water in lakes and ponds
freshwater plants may be rooted in the
littoral zone
At what time of year is the intensity of solar radiation striking each of Earth's hemispheres weakest? A) The intensity of solar radiation is weakest in the Southern Hemisphere in June and in the Northern Hemisphere in December. B) The intensity of solar radiation is weakest in the Northern Hemisphere in June and in the Southern Hemisphere in September. C) The intensity of solar radiation is weakest in the Southern Hemisphere in March and in the Northern Hemisphere in June. D) The intensity of solar radiation is weakest in the Northern Hemisphere in March and in the Southern Hemisphere in September.
A
If you are interested in observing a relatively simple community structure in a clear water lake, you would do well to choose diving into _____. A) an oligotrophic lake B) a relatively shallow lake C) a nutrient-rich lake D) a eutrophic lake
A
The range of cattle egrets has expanded between 1937 and today. How would an ecologist likely best explain the expansion of the cattle egret? A) The abundant area and little competition with other birds occupying similar habitats met the biotic and abiotic requirements of the cattle egret expansion. B) There are no predators for cattle egrets in the New World, so they continue to expand their range. C) The first egrets to colonize South America evolved into a new species capable of competing with the native species of herons and egrets. D) Climatic factors, such as sunlight, temperature, and precipitation, provide a suitable habitat for cattle egrets
A
Wetlands are standing bodies of freshwater, just like lakes and ponds. However, wetlands are different from lakes and ponds because wetlands have _____. A) shallow water and emergent vegetation B) emergent vegetation C) oxygen-poor water D) emergent vegetation and oxygen-poor water
A
What are the most abundant animals found in the pelagic zone? A) zooplankton B) cnidarians C) marine mammals D) dinoflagellates E) echinoderms
A
Which of the following is an important feature of most terrestrial biomes? A) vegetation demonstrating vertical layering B) a distribution predicted almost entirely by rock and soil patterns C) clear boundaries between adjacent biomes D) annual average rainfall in excess of 250 centimeters
A
Which of these is characteristic of the photic zone of a freshwater biome? A) the presence of algae B) relatively cool water C) relatively stable water temperature D) dead organic matter E) low oxygen level
A
Which statement regarding the June solstice is true? A) The Northern Hemisphere is tilted toward the sun. B) The Southern Hemisphere is tilted toward the sun. C) Locations in the Northern Hemisphere experience 12 hours of daylight and 12 hours of darkness. D) Locations in the Southern Hemisphere experience long days and short nights.
A
Which statements about dispersal are accurate? I) Dispersal is a common component of the life cycles of plants and animals. II) Colonization of devastated areas after floods or volcanic eruptions primarily depends upon climate. III) Seeds are important dispersal stages in the life cycles of most flowering plants. IV) Dispersal occurs only on an evolutionary time scale. A) only I and III B) only I, II, and IV C) only II and IV D) only II, III, and IV
A
Organisms evolve over generations to become adapted to the environmental conditions to which they are exposed. The diversity of organisms that occurs in any particular area thus may be largely determined by the abiotic factors limiting survivorship and reproduction of organisms in a region. Which of the following limit the range of Saguaro cactus in North America? I) pollinators II) sunlight III) precipitation IV) temperature A) only I and III B) I, II, III and IV C) only II, III, and IV D) only I, III, and IV
B
Suppose that the number of bird species is determined mainly by the number of vertical strata found in the environment. If so, in which of the following biomes would you find the greatest number of bird species? A) savanna B) temperate broadleaf forest C) tundra D) temperate grassland
B
Two plant species live in the same biome but on different continents. Although the two species are not at all closely related, they may appear quite similar as a result of _____. A) allopatric speciation B) convergent evolution C) introgression D) gene flow
B
What are the two major factors determining the distribution of terrestrial biomes? A) temperature and light B)temperature and rainfall C) light and rainfall D) plants and animals E) temperature and plants
B
Which of the following biomes spans the largest annual mean temperature range, but the narrowest mean precipitation range? A) tropical forest B) desert C) temperate forest D) taiga
B
Which of the following statements can be accurately made about light in aquatic environments? A) Most photosynthetic organisms avoid the surface where the light is too intense. B) Light penetration largely limits the distribution of photosynthetic species. C) Longer wavelengths penetrate to greater depths. D) Water equally reflects and absorbs all wavelengths of light.
B
Which of these environmental factor(s) is/are the key determining factor(s) that control(s) the biotic structure of aquatic biomes? A) average annual air temperature and precipitation B) oxygen concentrations and nutrient levels C) seasonal fluctuation of water temperature D) salinity
B
Which of these is the largest terrestrial biome on Earth? A) tundra B) coniferous forest C) temperate broadleaf forest D) temperate grassland E) desert
B
Aquatic biomes can be distinguished by chemical characteristics such as dissolved oxygen content and salinity and by physical characteristics such as water flow. Which five of the following statements about aquatic biomes are true? A) The lowest levels of dissolved oxygen in a stream are generally found in its turbulent headwaters. B) A freshwater organism permanently attached to the substrate would be unlikely to survive and reproduce in an estuary. C) All wetlands have soils that dry out periodically. D) Tropical coral reefs generally exist in relatively shallow areas of the ocean. E) Temperature drives water movement in some lakes. F) Wetlands have slow water movement or no water movement and no turnover. G) Estuaries are very productive and are used as breeding grounds by many species of fish.
B, D, E, F, G
A fish swimming into an estuary from a river would have which of the following as its greatest physiological challenge? A) The low oxygen content would give the fish difficulty in swimming aerobically. B) The high water flow would make the fish expend more energy. C) The change in water solute content would challenge the osmotic balance of the fish. D) The temperature change would stress the fish by denaturing its proteins.
C
If global warming continues at its present rate, which biomes will likely take the place of the coniferous forest (taiga)? A) desert and chaparral B) tropical forest and savanna C) temperate broadleaf forest and grassland D) chaparral and temperate broadleaf forest
C
If you conclude that vegetation at every point on Earth exactly resembles the predicted biome distribution in a climograph, then ________. A) the biome most sensitive (in danger) from global warming is the desert B) the biome spanning the smallest combined ranges in precipitation and temperature is the tundra C) you are ignoring the fact that local differences in soil, elevation, or topography can result in considerably different plant communities that are embedded within named biomes D) you are ignoring human land use changes or impacts, which have highly altered many regions within biomes
C
Imagine that a deep temperate zone lake did not turn over during the spring and fall seasons. Based on the physical and biological properties of limnetic ecosystems, what would be the difference from normal seasonal turnover? A) The lake would fail to freeze over in winter. B) An algal bloom of algae would result every spring. C) Lakes would suffer a nutrient depletion in surface layers. D) The pH of the lake would become increasingly alkaline.
C
In areas of permafrost, stands of black spruce are frequently observed in the landscape, while other tree species are noticeably absent. Often these stands are referred to as "drunken forests" because many of the black spruce often "lean over" (that is, they are displaced from their normal vertical alignment). What is the most likely explanation for the unusual growth of these forests in this marginal habitat? A) Trees tip so that they do not compete with each other for sunlight. B) Trees are tilted so snow prevents them from breaking or tipping over. C) Taproot formation is impossible, so trees developed shallow root beds. D) Branches are adapted to absorb more carbon dioxide with this displaced alignment.
C
In deep water, which of the following abiotic factors would most limit primary productivity? A) temperature B) chemical composition of the sea floor C) light availability D) solute concentration
C
Studying species transplants is a way that ecologists _____. A) determine the distribution of a species in a specified area B) consolidate a landscape region into a single ecosystem C) determine if dispersal is a key factor in limiting distribution of organisms D) develop mathematical models for distribution and abundance of organisms
C
The _____ biome is the largest of Earth's biomes. A) rain forest B) desert C) marine D) grassland E) freshwater
C
The ocean ecosystems affect the biosphere by ________. I) producing a substantial amount of the biosphere's oxygen II) adding carbon dioxide to the atmosphere III) being the source of most of Earth's rainfall IV) regulating the pH of freshwater biomes and terrestrial groundwater A) only I, II, and IV B) only II and IV C) only I and III D) only I, II, and III
C
Which biome is characterized by an extensive canopy that allows little light to penetrate to the ground and by the presence of epiphytes? A) temperate grassland B) coniferous forest C) tropical rain forest D) desert E) tundra
C
Which biome is characterized by the presence of permafrost? A) taiga B) tropical forest C) tundra D) coniferous forest E) desert
C
Which of the following statements best describes the interaction between fire and ecosystems? A) The likelihood of a wildfire occurring in a given ecosystem is highly predictable over the short term. B) Chaparral communities have evolved to the extent that they rarely burn. C) Many kinds of plants and plant communities have adapted to frequent fires. D) The suppression of forest fires by humans has prevented certain communities, such as grasslands, from reaching their climax stage.
C
Which of the following types of organisms is likely to have the widest geographic distribution? A) bears B) songbirds C) bacteria D) lizards
C
Which of these biomes is characterized by little rainfall? A) temperate broadleaf forest B) coniferous forest C) desert D) temperate grassland E) tropical rain forest
C
Which statement accurately describes Earth on February 21, a date that falls between the December solstice and the March equinox? A) Locations in the Northern Hemisphere experience less than 12 hours of darkness. B) The Southern Hemisphere experiences its longest day and shortest night of the year. C) Locations in the Southern Hemisphere experience more than 12 hours of daylight. D) In the Northern Hemisphere, there are more daylight hours than hours of darkness, but the difference is not as extreme as on the December solstice.
C
A certain species of pine tree survives only in scattered locations at elevations above 2800 meters in the western United States. To understand why this tree grows only in these specific places, an ecologist should _____. A) study the anatomy and physiology of this species B) collect data on temperature, wind, and precipitation at several of these locations for a year C) analyze the soils found in the vicinity of these trees, looking for unique chemicals that may support their growth D) investigate the various biotic and abiotic factors that are unique to high altitude
D
A(n) _____ is a region where fresh water and salt water mix. A) benthic zone B) intertidal zone C) aphotic zone D) estuary E) photic zone
D
The benthic zone of aquatic environments is defined as the _____. A) region that receives abundant sunlight B) region where phytoplankton are found C) region that receives little or no light D) substrate at the bottom of the body of water E) region that is flooded at high tide and not covered by water at low tide
D
Turnover of water in temperate lakes during the spring and fall is caused by which of the following? A) cold, more dense water layered at the bottom B) a distinct thermocline between less dense, warm water and cold, dense water C) warm, less dense water layered at the top D) the changes in the density of water as seasonal temperatures change
D
Which aquatic biome listed here is one of the most productive on Earth, and why? A) coral reef, diversity of organisms B) oligotrophic lake, clear water for light penetration C) deep-sea vent, warm water temperatures D) wetlands, nutrient rich high-moisture soils
D
Which of the following investigations is an example of the study of an abiotic factor? A) the relationship between finch beak size and food availability on two different Galapagos Islands B) observing interactions among various organisms in a rainforest canopy C) investigating how an elk population competes for food D) investigating how the amount of annual precipitation affects the distribution of a tree species E) identifying food sources for an egret population
D
Which of the following is responsible for the differences in summer and winter temperature stratification of deep temperate zone lakes? A) Stratification is caused by a thermocline. B) Winter ice sinks in the summer. C) Oxygen is most abundant in deeper waters. D) Water is most dense at 4°C.
D
Which of the following statements regarding turnover in a lake is correct? A) The surface water gets to 4°C only by cooling. B) In fall turnover, dense water at 4°C rises and disturbs sediments in the benthic zone. C) Fall turnovers and spring turnovers are exactly the same. D) In fall turnover, dense water at 4°C sinks and disturbs sediments in the benthic zone.
D
Which of the following causes Earth's seasons? A) global wind patterns B) vertical air circulation C) ocean currents D) changes in the Earth's distance from the sun E) Earth's tilt on its axis
E