1.
One characteristic of a stable ecosystem is
Correct Answer
B. An interdependence of organisms
Explanation
In a stable ecosystem, organisms rely on each other for survival and balance. This interdependence ensures that the ecosystem functions properly and maintains its equilibrium. Each organism plays a specific role and contributes to the overall health and well-being of the ecosystem. If one organism is disrupted or removed, it can have ripple effects throughout the ecosystem. Therefore, an interdependence of organisms is a key characteristic of a stable ecosystem.
2.
The burning of fossil fuels has harmed the environment by
Correct Answer
D. Adding carbon dioxide to the atmospHere
Explanation
The burning of fossil fuels releases carbon dioxide into the atmosphere. This is a well-known fact and has been extensively studied and documented. Carbon dioxide is a greenhouse gas that contributes to climate change and global warming. Therefore, adding carbon dioxide to the atmosphere is a harmful consequence of burning fossil fuels.
3.
Many biotic factors affect individuals in a population. An example of an organism being directly affected by a biotic factor is
Correct Answer
C. A squirrel cannot find a mate
Explanation
A squirrel not being able to find a mate is an example of an organism being directly affected by a biotic factor. This is because the ability to find a mate is crucial for reproduction and the survival of a population. If a squirrel cannot find a mate, it will not be able to reproduce and contribute to the growth and sustainability of its population. This directly impacts the individual squirrel and its ability to pass on its genetic material to future generations.
4.
Which statement best describes what is most likely to occur if an animal population grows larger than the carrying capacity of its environment?
Correct Answer
C. The death rate will increase.
Explanation
If an animal population grows larger than the carrying capacity of its environment, it means that there are more individuals than the environment can sustain. This leads to increased competition for resources such as food, water, and shelter. As a result, some individuals will not be able to access enough resources to survive, leading to an increase in the death rate. The limited resources cannot support the entire population, causing some individuals to die due to starvation, disease, or other factors. Therefore, the death rate will increase in this scenario.
5.
The hemlock wooly adelgid is an invasive insect species that is destroying native hemlock trees in New York State. These insects can upset natural ecosystems because they
Correct Answer
A. Disrupt habitats that native species depend on
Explanation
The hemlock wooly adelgid is an invasive insect species that disrupts habitats that native species depend on. This is because the adelgid feeds on the sap of hemlock trees, causing them to weaken and eventually die. As a result, the loss of hemlock trees disrupts the natural ecosystem by altering the availability of food and shelter for native species that rely on these trees. This can have cascading effects on other organisms within the ecosystem, leading to a decline in biodiversity and potentially causing population declines or even extinctions of native species.
6.
Humans have an effect on ecosystems when they use native grasslands or forested areas for farming or urban use. One Negative effect of these changes on the ecosystem is that there will be
Correct Answer
C. Less biodiversity
Explanation
When humans convert native grasslands or forests into farmland or urban areas, it leads to a reduction in biodiversity. This is because the natural habitats and ecosystems that support a wide range of plant and animal species are destroyed or fragmented. The loss of biodiversity can have negative consequences for the overall health and functioning of the ecosystem. It disrupts the delicate balance of species interactions, reduces genetic diversity, and can lead to the extinction of certain species. Therefore, the conversion of native habitats for human use ultimately results in less biodiversity.
7.
Many oak trees are cut down and removed from an oak-hickory forest. A likely result of the direct harvesting of the oak species would be the
Correct Answer
C. Disruption of natural cycles
Explanation
The direct harvesting of oak trees from an oak-hickory forest would likely result in the disruption of natural cycles. Oak trees play a crucial role in the ecosystem by providing food and habitat for various species. Their removal would disrupt the food chain and alter the balance of the ecosystem. Additionally, oak trees contribute to nutrient cycling and help maintain soil fertility. Removing them would interrupt this natural process, affecting the overall health and functioning of the forest ecosystem.
8.
Which statement describes an event that would most severely disrupt the process of ecological succession in an area?
Correct Answer
D. A dam is built on a river to form a reservoir.
Explanation
Building a dam on a river to form a reservoir would most severely disrupt the process of ecological succession in an area. This is because the construction of a dam would alter the natural flow of water, leading to changes in the habitat and the availability of resources for plants and animals. It would disrupt the natural balance of the ecosystem, potentially causing the displacement or extinction of certain species and preventing the establishment of new ones. This human intervention would have a significant and lasting impact on the ecological succession process in the area.
9.
Although we rely on coal, oil, and natural gas to produce energy, some environmental scientists have proposed that we use less fossil fuel. One reason to support this proposal is to
Correct Answer
C. Help us to reduce the production of carbon dioxide gas
Explanation
Using less fossil fuel would help us to reduce the production of carbon dioxide gas. Fossil fuels, such as coal, oil, and natural gas, release carbon dioxide when burned for energy. Carbon dioxide is a greenhouse gas that contributes to climate change and global warming. By reducing our reliance on fossil fuels, we can decrease the amount of carbon dioxide emissions, which would have a positive impact on the environment and help mitigate climate change.
10.
Abandoned farmland that once grew corn is now covered with bushes and small tress. These observed changes resulted directly from
Correct Answer
C. Ecological succession
Explanation
Ecological succession refers to the process of a gradual and predictable change in the species composition and structure of an ecological community over time. In this scenario, the abandoned farmland has undergone ecological succession as it has transitioned from growing corn to being covered with bushes and small trees. This change is a result of natural processes such as the establishment and growth of different plant species, which gradually transform the ecosystem.
11.
When rain forests are cut down, there is a
Correct Answer
A. Loss of genetic material available for research
Explanation
When rain forests are cut down, there is a loss of genetic material available for research. Rainforests are known to contain a vast array of plant and animal species, many of which have unique genetic characteristics. These genetic materials are valuable for scientific research, as they can be studied to develop new medicines, improve crop yields, and understand evolutionary processes. Therefore, when rainforests are destroyed, the loss of these genetic materials hinders the progress of scientific research and potential discoveries.
12.
Before a new shopping center can be built on previously undeveloped land, the builders must submit a proposal to the local government for approval. Which statement identifies an environmental concern associated with the development of the shopping center?
Correct Answer
A. Building the center would decrease resources needed by local organisms.
13.
Scientists have studied the return of plant life on Mount St. Helens ever since the volcano erupted in 1980. Wildflowers began colonizing the area, followed by shrubs and small trees. Scientists predict that it will likely take hundreds of years before the area returns to a forest dominated by fir and hemlock trees. These changes are an example of
Correct Answer
A. The growth of a forest through ecological succession
Explanation
The given information states that after the eruption of Mount St. Helens, plant life started to return in a specific order, with wildflowers, shrubs, and small trees colonizing the area. The statement also mentions that it will take hundreds of years for the area to return to a forest dominated by fir and hemlock trees. This process of plant colonization and succession, where different plant species gradually replace each other over time, is known as ecological succession. Therefore, the correct answer is the growth of a forest through ecological succession.
14.
As a result of habitat destruction, the size of the Florida panther population has been drastically reduced. It is estimated that there are only 100 to 160 Florida panthers in the wild. Which statement best explains why the Florida panther population may NOT continue to evolve?
Correct Answer
B. There is a lack of genetic variation for selection to act upon.
Explanation
The statement "There is a lack of genetic variation for selection to act upon" best explains why the Florida panther population may not continue to evolve. Genetic variation is essential for natural selection to occur, as it allows for the survival and reproduction of individuals with advantageous traits. With a lack of genetic variation, there is limited potential for adaptive changes in the population, making it difficult for the Florida panthers to adapt to their changing environment and continue evolving.
15.
Which row represents the most likely changes int he atmosphere due to widespread deforestation?
Correct Answer
B. Oxygen Decreases, Carbon Dioxide Increases
Explanation
Widespread deforestation refers to the cutting down of trees on a large scale. Trees play a crucial role in the process of photosynthesis, where they absorb carbon dioxide and release oxygen. Therefore, when deforestation occurs, there is a decrease in the number of trees available to absorb carbon dioxide, leading to an increase in its concentration in the atmosphere. Additionally, with fewer trees, there is a decrease in the amount of oxygen being released through photosynthesis, resulting in a decrease in oxygen levels in the atmosphere. Hence, the most likely changes in the atmosphere due to widespread deforestation are a decrease in oxygen and an increase in carbon dioxide.
16.
Monarch butterflies migrate from the US and Canada to Mexico every winter. Over the past 10 years, there has been a drastic decrease in the number of monarch butterflies. Scientists have estimated that the population may have decreased from about 1 billion to 35 million. Which action would NOT be considered a reason for the decline in monarch butterfly populations?
Correct Answer
B. Habitat preservation
17.
Homeowners have been encouraged to learn how to identify invasive plants and to remove them if they find them. The most likely reason for removing invasive plants is to
Correct Answer
C. Preserve biodiversity
Explanation
Removing invasive plants is done to preserve biodiversity. Invasive plants can outcompete native plants and disrupt the balance of ecosystems. By removing invasive plants, homeowners can help protect the native plant species and maintain a diverse range of plant life. This, in turn, supports the overall health and stability of the ecosystem and promotes the survival of various animal species that depend on native plants for food and habitat.
18.
Which method of collecting data would provide the most accurate information about how an ecosystem is being affected by human development?
Correct Answer
D. The population size is recorded for each species present in the construction area before and after the building is completed.
Explanation
Recording the population size for each species present in the construction area before and after the building is completed would provide the most accurate information about how an ecosystem is being affected by human development. This method would allow scientists to directly observe and measure the impact of the construction on the species' populations, providing quantitative data on the changes in the ecosystem. By comparing the population sizes before and after the building is completed, scientists can assess the extent of the impact and determine how the ecosystem is being affected by human development.
19.
Some states require shoppers to pay a deposit on certain beverage containers made of plastic and glass. When shoppers return the containers, their deposits are returned to them. How is this system intended to help the environment?
Correct Answer
C. It reduces the amount of plastics and glass put into landfills.
Explanation
The system of requiring shoppers to pay a deposit on certain beverage containers made of plastic and glass is intended to help the environment by reducing the amount of plastics and glass put into landfills. This is because when shoppers return the containers and receive their deposits back, they are incentivized to recycle the containers instead of throwing them away. By recycling these materials, less waste ends up in landfills, reducing the environmental impact and promoting sustainability.
20.
For centuries, humans have used resources from coastal areas and open ocean waters. An example of an activity that would promote the conservation of coastal areas and ocean resources is
Correct Answer
A. Creating protected zones of natural grasses and shrubs in beach areas
Explanation
Creating protected zones of natural grasses and shrubs in beach areas would promote the conservation of coastal areas and ocean resources. This activity would help preserve the natural habitat and biodiversity of these areas, providing a safe space for various species to thrive. It would also prevent erosion and protect the coastline from damage caused by human activities. By creating protected zones, it encourages responsible and sustainable use of coastal resources, ensuring their long-term availability for future generations.
21.
Scientists have recently discovered a community of bacteria and clams living under an ice shelf in Antarctica. These organisms live under 600 feet of ice, in the absence of sunlight, and in temperatures considered too cold for most living organisms. The location where these organisms live is unusual because
Correct Answer
C. Of the abiotic factors found in their environment
Explanation
The location where these organisms live is unusual because of the abiotic factors found in their environment. The presence of 600 feet of ice, absence of sunlight, and extremely cold temperatures make it a challenging habitat for most living organisms. These abiotic factors create a unique environment that only a few specialized organisms, such as bacteria and clams, can adapt to and survive in.
22.
Ecologists are concerned that the golden-winged warbler population is at a dangerously low level. One reason this could lead to extinction of this warbler is that
Correct Answer
B. There may not be enough diversity among the birds for the species to be able to survive an environmental change
Explanation
The golden-winged warbler population being at a dangerously low level could lead to extinction because there may not be enough diversity among the birds for the species to be able to survive an environmental change. Lack of genetic diversity makes a population more vulnerable to diseases, changes in habitat, and other environmental factors. Without a diverse gene pool, the warblers may not have the necessary adaptations to adapt and survive in different conditions, ultimately leading to their extinction.
23.
In the 1920s, over 25 million acres of the American southern plains were stripped of prairie grasses to provide more land for farmers to grow wheat. The prairie grasses had served to hold the soil in place and prevent erosion. In the early 1930s, a series of severe dust storms eroded topsoil from more than 13 million acres of the southern plains and dumped it as tons of dust particles over many cities in the the Northeast. Farmland was destroyed and people were sickened from "dust pneumonia." This occurrence illustrates
Correct Answer
D. When humans alter ecosystems, serious consequences may result
Explanation
The given passage describes how the clearing of land for farming in the southern plains led to severe dust storms and the destruction of farmland. This illustrates that when humans alter ecosystems, serious consequences may result.
24.
After feeding at the surface of the ocean during the day, many ocean organisms migrate to deeper waters. While there, they release ammonia in their urine. Many bacteria use the nitrogen from the ammonia as they make amino acids, which eventually end up in food chains on both land and water. These amino acids may even be used in humans. Which statement best explains these observations?
Correct Answer
A. Chemical elements, including nitrogen, pass through food webs and are combined and recombined in different ways.
Explanation
The explanation for the given correct answer is that chemical elements, including nitrogen, pass through food webs and are combined and recombined in different ways. This is evident from the fact that ocean organisms release ammonia in their urine, which is then used by bacteria to make amino acids. These amino acids eventually end up in food chains on both land and water, and may even be used in humans. This demonstrates the transfer and transformation of nitrogen and other chemical elements within food webs, highlighting the interconnectedness of ecosystems.
25.
Rabbits are not native to Australia. They were imported by European settlers. In 1936, the myxoma virus was introduced into Australia as a means of biological control to infect and reduce the rabbit population. this method of controlling the rabbit population was an attempt to
Correct Answer
A. Stop the overproduction of an introduced species
Explanation
The introduction of the myxoma virus in Australia was an attempt to control the rabbit population, which had been introduced by European settlers. The virus was intended to reduce the overproduction of rabbits, which were not native to Australia. Therefore, the correct answer is to stop the overproduction of an introduced species.