Critical Thinking Questions

38.
Define and describe community ecology. Give an example.
  1. It is the study of the number of individuals of one species in an area as well as how and why the number changes over time. An example would be counting the number of individuals of the Karner blue butterfly, a federally endangered species whose population density is highly influenced by the abundance of wild lupine.
  2. It is the study of the processes and consequences of interactions within and among different species within an area. An example would be the work of scientists who work in a marsh studying the various interactions of several populations of birds, crabs, and grasses in a marsh without studying the water or air quality.
  3. It is the study of the physiological, morphological, and behavioral adaptations that enable individuals to live in specific habitats. An example would be the work of scientists who study the various interactions of several populations of birds, crabs, and grasses in a marsh without studying the water or air quality.
  4. It is the study of the processes and consequences of interactions within and among different species within an area. An example would be counting the number of individuals of the Karner blue butterfly, a federally endangered species whose population density is highly influenced by the abundance of wild lupine.
39.
Ecologists often collaborate with other researchers interested in ecological questions. Which levels of ecology would most easily lend themselves to collaborative research because of the similarities in the scope of questions asked?
  1. Community and ecosystem ecology
  2. Organismal and community ecology
  3. Population and biome ecology
  4. Ecosystem and population ecology
40.
How do organisms return nutrients and water to the environment?
  1. By cycling between the abiotic and biotic environment.
  2. By cycling between evaporation and transpiration.
  3. By cycling between the flora and fauna of the Earth.
  4. By cycling between temperature and moisture.
41.
Define and give an example of organismal, population and community ecology.
  1. Organismal ecology includes the study of the number of individuals in an area as well as how and why population size changes over time, such as a study of the drop in antelope population. Population ecology includes the study of adaptations that enable individuals to live in specific habitats, such as a study of the use of opposable thumbs. Community ecology includes the study of the processes and consequences of interactions within and among different species in an area, such as a study of interactions between wolves and deer.
  2. Organismal ecology includes the study of the processes and consequences of interactions within and among different species in an area, such as a study of the interactions between wolves and deer. Population ecology includes the study of the number of individuals in an area as well as how and why population size changes over time, such as a study of the drop in antelope population. Community ecology includes the study of adaptations that enable individuals to live in specific habitats, such as a study of the use of opposable thumbs.
  3. Organismal ecology includes the study of adaptations that enable individuals to live in specific habitats, such as a study of the use of opposable thumbs. Population ecology includes the study of the number of individuals in an area as well as how and why population size changes over time, such as a study of the drop in antelope population. Community ecology includes studies of the processes and consequences of interactions within and among different species in an area, such as a study of the interactions between wolves and deer.
  4. Organismal ecology includes studies of the adaptations that enable individuals to live in specific habitats, such as a study of the use of opposable thumbs. Population ecology includes studies of the processes and consequences of interactions within and among different species in an area, such as a study of the interactions between wolves and deer. Community ecology includes studies of the number of individuals in an area as well as how and why population size changes over time, such as a study of the drop in antelope population.
42.
Many endemic species are found in areas that are geographically isolated. Suggest a plausible scientific explanation why this is so.
  1. Geographically isolated areas are usually warmer than other areas, and high temperatures promote rapid mutation and development of unique characteristics compared with cooler temperatures. Over time, these species retained their unique characteristics because they remained separated from other species.
  2. Geographically isolated areas have provided a unique environment for certain species to evolve. Over time, these species retained their unique characteristics because they remained separated from other species.
  3. Certain species are introduced into some geographically isolated areas, which provide them unique environments. Over time, these species retained their unique characteristics because they remained separated from other species.
  4. A unique environment is provided for certain species to evolve in vitro and these species are introduced into geographically isolated areas. Over time, these species retained their unique characteristics because they remained separated from other species.
43.
The American white pelican migrates from North America to Central America in the winter months. Why do these birds follow an annual migration pattern?
  1. The American white pelican follows an annual migration pattern in search of cooler climates. Cooler climates make it easier for them to maintain a constant body temperature than if they stayed somewhere warm.
  2. The American white pelican follows an annual migration pattern in search of food, saltwater, and cooler climates. Cooler climates help these birds reproduce.
  3. The American white pelican follows an annual migration pattern in search of food and warmer climates. Warmer climates and greater food availability make it easier to maintain a constant body temperature than if they stayed somewhere cold.
  4. The American white pelican follows an annual migration pattern in search of food only. Warmer climates have greater food availability, and pelicans can maintain their body temperature equally easily in cold versus warm temperatures.
44.
Why is it essential for organisms to maintain a relatively constant body temperature? Describe adaptations that help the organisms cope with changes in environmental temperature.
  1. The rate of metabolic processes increases at very high or low temperatures. So, organisms have to maintain a constant body temperature. This can be achieved only by migration to avoid seasonal temperature changes.
  2. Enzymes that carry out metabolic processes are denatured at very high temperatures and work more slowly at lower temperatures. So, organisms have to maintain a constant body temperature. This can be achieved by hibernation, aestivation, or migration.
  3. The rate of metabolic processes increases at very high or low temperatures. So, organisms have to maintain a constant body temperature. This can be achieved by hibernation, aestivation, or migration.
  4. Enzymes that carry out metabolic processes are denatured at very high temperatures. So, organisms have to maintain a constant body temperature. This can be achieved only by migration to avoid seasonal temperature changes.
45.
The extremely low precipitation of subtropical desert biomes might lead one to expect fire to be a major disturbance factor. However, fire is more common in the temperate grassland biome than in the sub tropic desert biome. Why is this?
  1. Due to higher net primary productivity, biomass in deserts is significantly more than in temperate grassland biomes. However, it is easier for fire to spread in grasslands as biomass is abundant.
  2. Due to lower net primary productivity, biomass in deserts is significantly less than in temperate grassland biomes. It is easier for fire to spread in grasslands as biomass is abundant.
  3. Due to lower net primary productivity, biomass in deserts is significantly less than in temperate grassland biomes. It is easier for fire to spread in grasslands as they have very low precipitation and high temperatures.
  4. Due to higher net primary productivity, biomass in deserts is significantly more than in temperate grassland biomes. However, it is easier for fire to spread in grasslands as they have very low precipitation and high temperatures.
46.
What are endemic species? Give an example and explain how endemic species differ from generalist species.
  1. Endemic species are found naturally in specific geographic areas that are usually restricted in size. For example, the raccoon is found only in Australia. Generalist species are found in a wide range of geographical locations. For example, the koala is native to most of North and Central America.
  2. Endemic species are defined as those that are likely to be extinct. For example, the Tasmanian tiger (a marsupial) was found only in Australia but became extinct. Generalist species are those found in a wide range of geographical locations and are less likely to become extinct. For example, the raccoon is native to most of North and Central America and is not endangered.Endemic species are found in a wide range of geographical locations. For example, the koala (a marsupial) is found only in Australia. Generalist species are found naturally in specific geographic areas that are usually restricted in size. For example, the raccoon is native to most of North and Central America.
  3. Endemic species are found in a wide range of geographical locations. For example, the raccoon is native to most of North and Central America. Generalist species are found naturally in specific geographic areas that are usually restricted in size. For example, the koala is only found in some regions of Australia.
  4. Endemic species are found naturally in specific geographic areas that are usually restricted in size. For example, the koala is found only in some regions in Australia. Generalist species are found in a wide range of geographical locations. For example, the raccoon is native to most of North and Central America.
47.
Deserts and subtropical deserts experience low precipitation and extremes in temperature. For a plant to survive and reproduce, what adaptations should it have? Why?
  1. To survive, they need prop roots, reduced foliage and fleshy leaves with sunken stomata to reduce transpiration. Also, they should have seeds that can remain dormant over long periods.
  2. To survive, they need deep roots, reduced foliage and fleshy leaves with sunken stomata to reduce transpiration. Also, they should have seeds that can remain dormant over long periods.
  3. To survive, they need deep roots, reduced foliage and fleshy leaves with sunken stomata to reduce transpiration. Also, these plants need to grow in clumps.
  4. To survive, they need deep roots, increased foliage, and fleshy leaves with sunken stomata to reduce transpiration. Also, the plants need seeds that can remain dormant over long periods.
48.
In what ways are the subtropical desert and the arctic tundra similar?
  1. Both are characterized by animals, which are adapted to burrowing.
  2. Both are characterized by plants, which prefer to grow in clumps.
  3. Both are characterized by low water availability and, as a result, low net primary productivity.
  4. Both are characterized by plants, which are mostly perennials.
49.
Describe the chaparral biome. How does it differ from subtropical deserts?
  1. Shrubs dominate chaparral vegetation and are well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their high precipitation and water-retaining plants.
  2. Shrubs dominate chaparral vegetation and are well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their low precipitation and water-retaining plants.
  3. Lichens dominate chaparral vegetation and are well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their low precipitation and water-retaining plants.
  4. Shrubs dominate chaparral vegetation but are not well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their low precipitation and water-retaining plants.
50.
What happens to aquatic life in deep lakes when water freezes during the winter months?
  1. During winters, layer of ice forms on water surface, as ice is less dense than water. Water is densest at 7° C and retains its liquid form below the water surface. The aquatic life can exist in liquid water.
  2. During winters, the aquatic life exists in liquid water, which is present between layers of ice, by consuming more resources so it can survive during the harsh winter season.
  3. During winters, a layer of ice forms on the water surface, as ice is less dense than water. Water is densest at 4°C and retains its liquid form below the water surface, where the ice layer is. In liquid water, the aquatic life can survive using the resources available.
  4. During winters, ice forms only on the surface and a few meters below the surface of water. Water is densest at 4°C and retains its liquid form below the water surface, where the ice layer is. In liquid water, the aquatic life can exist using the resources available.
51.
Explain the challenges facing organisms living in the intertidal zone and their adaptations to meet these challenges.
  1. They are subject to constant exposure to air, sunlight, periods of dryness, and pounding waves. For this reason, some species have an exoskeleton.
  2. They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, some species have an exoskeleton.
  3. They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, all species have an exoskeleton.
  4. They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, most species have an endoskeleton.
52.
If algae grows out of proportion as seen during algal blooms, how does it affect the ecosystem?
  1. Other photosynthetic organisms will not be able to grow. The animals and birds that live on those organisms will be affected. As the algae die, oxygen will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
  2. Non-photosynthetic organisms will not be able to grow due to lack of light. The photosynthetic organisms that require them to live will be affected. As the algae die, oxygen will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
  3. Other photosynthetic organisms will not be able to grow. The animals and birds that live on those organisms will be affected. As the algae die, carbon dioxide will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
  4. Non-photosynthetic organisms will not be able to grow. The animals and birds that live on those organisms will be affected. As the algae die, carbon dioxide will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
53.
What are some abiotic factors that affect freshwater biomes? Explain.
  1. Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes require high salt density for survival, its depletion would kill the organisms. Many organisms that serve as food for others are photosynthetic and would die if algae blooms obscured the light. Their decomposition as well as the depletion of oxygen by algae would cause organisms that require oxygen to die out as well.
  2. Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes cannot tolerate high salt levels, these organisms would not survive if it increased. Many organisms that serve as food for others are photosynthetic would die if algal blooms obscured the light. Their decomposition and the depletion of carbon dioxide by algae would cause organisms that require carbon dioxide to die out as well.
  3. Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes cannot tolerate high salt levels, these organisms would not survive if it were to increase significantly. Many organisms that serve as food for others are photosynthetic and would die if algal blooms obscure light. Their decomposition and depletion of oxygen by algae would cause organisms that require oxygen to die out as well.
  4. Salinity and temperature are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes cannot tolerate low salt concentrations, those organisms would not survive if salt concentrations fell significantly. Many organisms that serve as food for others are photosynthetic and would die if algal blooms obscured the light. Their decomposition and the depletion of oxygen by algae would cause organisms that require oxygen to die out as well.
54.
Is it possible to reverse global warming? What measures may help in reducing global climate change?
  1. Because it has not yet affected ecosystems, it is possible to reverse global warming by reducing the usage of fossil fuels, using alternative fuels, using alternatives to CFCs, and using natural sources of energy.
  2. It is not possible to reverse global warming since major climate changes have already occurred and settled in the environment. Reducing fossil fuel usage, using natural sources of energy, and using alternative fuels are sufficient to slow down future global climate change.
  3. It may not be possible to reverse global warming as we are already witnessing changes in the environment, plants, and animal behavior. However, taking multiple steps including reducing fossil fuel usage and using natural sources of energy may slow down global climate change.
  4. It is possible to reverse global warming by working on new technologies that will help in preventing temperature changes worldwide. Using wind power and high-efficiency natural gas generation will be sufficient to achieve this goal.
55.
As global temperatures change, many flowering plants are flowering earlier. What change would most likely occur if the insect pollinators are not around at the same time?
  1. Insects will be deprived of their nectar, leading to decrease in numbers; but flowering plants will not be affected, as other animals will pollinate them.
  2. Flowering plants will not be pollinated resulting in their less population; but insects will not be affected, as insects will feed on other organisms.
  3. Neither plants nor pollinators will be affected, as new or different species of insects are going to pollinate the flowering plants.
  4. Both plant and pollinator numbers would decrease, as insects will be deprived of nectar and plants will not be pollinated.
56.
If scientists had to predict the rise in Earth’s temperature in the next one hundred years, what would they take into consideration?
  1. Scientists can predict the change in earth’s temperature only by analyzing previous and current data such as dimensions and locations of glaciers as well as the water levels in lakes, rivers, and oceans.
  2. Scientists could predict rise in temperature by analyzing previous and current data like dimensions and locations of glaciers, water levels in lakes, rivers and oceans and by the number of annual rings in trees.
  3. Scientists could predict rise in earth’s temperature by measuring the greenhouse gases present in the current atmosphere. Counting and examining the number of annual rings in trees would provide information about past temperature changes.
  4. Scientists can predict the change in earth’s atmosphere by counting and analyzing the number of annual rings in trees. Also, analyzing ice cores for over a year would predict the rise in Earth’s temperature in the next one hundred years.
57.
Many people cannot imagine a world without fossil fuels, but fossil fuels are finite resources and will eventually run out. This is why drilling had begun in Arctic in an effort to find a new source of fossil fuels, though it is currently stopped. What are the dangers of drilling in the Arctic? What are the alternatives?
  1. Drilling as well as melting of ice in the Arctic affects organisms there and results in the release of large amounts of methane, accelerating global warming. Investing in clean energy like wind, water, and solar power, which do not release harmful gases, could be the alternative.
  2. Drilling as well as melting of ice in the Arctic results in the release of large amounts of carbon monoxide, accelerating global warming. Investing in clean energy like wind, water, and solar power, which do not release harmful gases, could be the alternative.
  3. Drilling as well as melting of ice in the Arctic results in the release of large amounts of carbon monoxide, which is lethal. Investing in clean energy like wind, water, and solar power, which do not release harmful gases, could be the alternative.
  4. Drilling as well as melting of ice in the Arctic results in the release of large amounts of methane, accelerating global warming. Investing in mining of earth minerals and metal ores could be the alternative.