Bio Test 4 (Ch. 15)

In a trophic level, only about 10% of the energy is available to the next trophic levels. This is due to the energy loss that occurs as energy is transferred from one trophic level to another. The majority of the energy is lost as heat during metabolic processes such as respiration and digestion, leaving only a small fraction of the energy to be passed on to the next level.

An ecosystem consists of all the living organisms and all the abiotic factors that influence living organisms. This includes not only the plants and animals present in the area, but also the non-living components such as temperature, sunlight, water, and soil composition. All these factors interact with each other and contribute to the overall functioning and balance of the ecosystem.

Carbon dioxide, CO2, is the correct answer because it is the most abundant carbon compound in the Earth's atmosphere. It is produced through natural processes such as respiration and volcanic activity, as well as human activities like burning fossil fuels. Carbon dioxide plays a significant role in the greenhouse effect and climate change. Chlorofluorocarbons (CFCs) are synthetic compounds that were once commonly used in aerosol propellants and refrigerants, but they have been phased out due to their harmful effects on the ozone layer. Carbohydrates, methane, and carbonic acid are also carbon compounds, but they are not as prevalent in the atmosphere as carbon dioxide.

An ecosystem is a complex system that includes various components such as the physical environment, organisms, and their interactions. The average temperature of a locality is an important factor that influences the distribution and behavior of organisms within an ecosystem. An ecosystem consists of multiple communities, which are groups of different species living together in a particular area. Bacteria and fungi are essential components of an ecosystem as they play crucial roles in nutrient cycling and decomposition. Additionally, an ecosystem includes chemical resources such as water, minerals, and gases that are necessary for the survival and functioning of organisms. Therefore, all of the statements mentioned in the options are true about an ecosystem.

Keystone species are those that have a disproportionately large impact on their ecosystem relative to their abundance. In the case of bison and starfish, they are considered keystone species because their presence or absence can greatly influence the diversity and structure of their respective communities. Bison, for example, play a crucial role in maintaining the grasslands by grazing on dominant plant species, which allows for a greater variety of plant species to thrive. Similarly, starfish are known to control the populations of mussels and other prey species, thereby preventing competitive exclusion and promoting biodiversity in rocky seashore communities.

Competitive exclusion refers to the process where one species outcompetes and drives another species to local extinction by utilizing the same limited resources. This occurs when two species have similar ecological niches and compete for the same resources such as food, shelter, or space. The species that is better adapted or more efficient in resource utilization will eventually dominate and exclude the other species from the habitat. This process is a result of intense competition and is a key mechanism in shaping community structure and species interactions.

The correct answer is "all of the above" because Earth's largest ecosystems, biomes, are defined primarily by the combination of seasonal variability in rainfall, average rainfall, average temperature, and seasonal variability in temperature. These factors play crucial roles in determining the types of plants and animals that can thrive in a particular biome. The interaction between rainfall and temperature patterns influences the availability of water and the length of growing seasons, which ultimately shape the characteristics of different biomes around the world.

Tertiary consumers are carnivores that eat other carnivores. This means that they are at the top of the food chain and feed on other animals that also eat meat. They are not herbivores, which eat plants, or detritivores, which feed on dead organic matter. Tertiary consumers play an important role in controlling the population of other carnivores, and their presence helps maintain the balance of the ecosystem.

Biomass refers to the total dry weight of an organism in an ecosystem. It includes all the living and non-living organic matter present in an organism, such as plants, animals, and microorganisms. Biomass is an important measure of the amount of energy stored in an ecosystem and represents the potential food available for other organisms in the food chain. It is a crucial factor in understanding the overall health and productivity of an ecosystem.

The correct answer is "consume carnivores primarily". This means that top carnivores primarily feed on other carnivores for their energy and nutrition. They are at the highest level of the food chain and play a crucial role in regulating the population of lower trophic levels. By consuming carnivores primarily, they help maintain the balance of the ecosystem and ensure the transfer of energy from one trophic level to another.

The answer "carbon, oxygen, hydrogen, nitrogen, phosphorus" is correct because these five elements are essential components of biological molecules found in all living organisms. Carbon is the backbone of organic compounds, while oxygen and hydrogen are present in water and many other biomolecules. Nitrogen is a key component of proteins and nucleic acids, and phosphorus is found in nucleic acids and ATP, the energy currency of cells. Together, these elements make up a significant portion of the biomass in plants, animals, fungi, and bacteria.

The angle of the sunlight is an important determinant of the amount of solar energy received because it affects the intensity of the sunlight. When the sun is directly overhead, the sunlight is more intense and provides more solar energy. However, when the sun is at a lower angle, the sunlight has to pass through a larger portion of the atmosphere, which reduces its intensity and the amount of solar energy received. Therefore, the angle of the sunlight plays a crucial role in determining the amount of solar energy received in a given location.

Different places receive different amounts of solar energy due to the tilt of the Earth's axis and its rotation around the sun. This causes variations in the angle and intensity of sunlight reaching different parts of the Earth, resulting in variations in climate. Regions closer to the equator receive more direct sunlight and therefore tend to be warmer, while regions closer to the poles receive less direct sunlight and tend to be colder. This difference in solar energy received is a primary factor in determining the climate patterns observed in different parts of the Earth.

When resources are used by more than one species, the initial result is competition. This is because different species will compete for the limited resources available in their environment. This competition can involve various strategies, such as fighting, territoriality, or even altering behavior or physiology to gain an advantage over other species. Ultimately, competition can lead to the extinction of certain species if they are unable to effectively compete for the necessary resources.

Seastars in the intertidal zone are an example of a keystone predator. Keystone predators play a crucial role in maintaining the balance of an ecosystem by controlling the population of their prey species. In the intertidal zone, seastars feed on mussels and other shellfish, preventing them from dominating the habitat and allowing other species to thrive. The removal of seastars from the ecosystem can lead to a cascade effect, causing a decline in biodiversity and disrupting the overall functioning of the ecosystem.

An organism's role in its environment is referred to as its niche. A niche includes the specific way an organism interacts with its surroundings, such as its behavior, habitat, and the resources it uses. It also encompasses the organism's position in the food chain and its relationships with other species. The concept of a niche helps us understand how different organisms coexist and adapt to their environment.

In a food web, secondary consumers are organisms that feed on primary consumers. In this given food web, the sparrows feed on grasshoppers, which are primary consumers. Therefore, sparrows are classified as secondary consumers.

A habitat is the specific area where an organism lives, while a community refers to all of the different organisms that exist in a particular area at a given time.

The given answer states that all of the options correctly identify one of the several methods of energy extraction. This means that each option accurately describes a method by which organisms obtain energy. Therefore, there is no option that does NOT correctly identify a method of energy extraction.

Mean annual rainfall in an ecosystem is an example of an abiotic factor because it is a non-living component that affects the ecosystem. Abiotic factors are physical or chemical factors that influence the organisms in an ecosystem, and rainfall is one of these factors. It can affect the availability of water for organisms, influence the growth of plants, and impact the overall climate and environment of the ecosystem.

Humans take multiple actions to increase the primary productivity of specific plants. They breed higher-yielding strains of plants, which are genetically modified to produce more biomass or yield more crops. Increasing the availability of water through irrigation or other means helps plants to grow and photosynthesize more efficiently. Reducing competition from other plants by removing weeds or using herbicides allows the target plants to access more resources. Adding nutrients to the soil, such as fertilizers, provides essential elements for plant growth and enhances their productivity. Therefore, all of the mentioned actions contribute to increasing the primary productivity of specific plants.

The amount of solar energy received by an area is the primary factor affecting its climate. Solar energy determines the temperature of an area, which in turn influences other climatic factors such as wind patterns, humidity, and precipitation. Areas that receive more solar energy tend to have warmer climates, while areas with less solar energy have cooler climates. Solar energy also drives the water cycle, which is responsible for the distribution of moisture and precipitation in an area. Therefore, the amount of solar energy received is crucial in determining the overall climate of an area.

Phosphorus is an essential chemical that is stored in the soil. It is a vital nutrient for plant growth and development, as it plays a key role in energy transfer and storage, DNA formation, and cell division. Plants obtain phosphorus from the soil through their roots, and it is necessary for the production of ATP, which is the energy currency of cells. Therefore, the soil acts as a reservoir for phosphorus, providing plants with this essential chemical for their growth and survival.

The "competitive exclusion principle" states that no two species competing for the same resources can stably coexist. This means that if two species have similar ecological niches and rely on the same resources, one species will eventually outcompete and eliminate the other. This principle is based on the idea that resources are limited, and any advantage one species has over another will ultimately lead to the exclusion of the weaker species. Therefore, in order for multiple species to coexist in a community, they must have different resource requirements or occupy different niches.

The tundra biome receives the lowest average yearly precipitation compared to the other biomes listed. This is because the tundra is a cold and dry region located near the Earth's poles, where the air is generally colder and holds less moisture. The low temperatures in the tundra also limit the amount of evaporation, further reducing the amount of precipitation that falls. As a result, the tundra biome is characterized by its cold and arid conditions, with very little rainfall throughout the year.

Parasitism can be considered a special form of predation because it involves one organism (the parasite) benefiting at the expense of another organism (the host). In predation, one organism kills and consumes another organism for its own survival and nutrition. Similarly, parasites rely on their hosts for resources and often harm or weaken the host in the process. This relationship is different from competition, commensalism, and mutualism, as it involves one organism actively harming and feeding on another.

Secondary succession occurs when an existing ecosystem is disrupted or destroyed, but the soil is still intact. In this scenario, the mature deciduous forest is cut down for timber, causing the ecosystem to be disturbed. However, new seedlings begin to appear the following year, indicating that the ecosystem is starting to recover and undergo secondary succession. This process involves the gradual recolonization of plants and animals in the area, leading to the reestablishment of a new community over time.

The correct answer is "it allows for only one organism to survive in the niche". This statement is incorrect because a niche can be occupied by multiple species as long as they have different resource requirements or utilize different parts of the niche. Multiple species can coexist in a niche through resource partitioning, where each species occupies a slightly different ecological niche to avoid direct competition.

The correct answer is false because food chains do not accurately represent the complexity of energy flow through an ecosystem. Real ecosystems are much more complex, with multiple interconnected food chains, energy transfers between trophic levels, and the recycling of nutrients. Food chains only depict the linear flow of energy from one organism to another, without considering the multitude of interactions and pathways that occur in real ecosystems.

When moist air masses encounter a mountain, they are forced to rise. As the air rises, it cools and condenses, leading to precipitation on the windward side of the mountain. By the time the air reaches the other side of the mountain, it has lost much of its moisture, resulting in very little moisture availability. This lack of moisture creates dry conditions, which are characteristic of deserts. Therefore, the correct answer is that moist air masses are forced to rise over mountains and lose their moisture, leading to deserts on the other side.

The Gulf Stream is a warm ocean current that brings warm water from the Gulf of Mexico to the UK, which helps to moderate its climate. Without this current, the climate of the UK would be much colder and more similar to that of Scandinavia, which is known for its colder temperatures. Therefore, the correct answer is that the climate of the UK would be similar to that of Scandinavia.

When the sun is low in the sky, the amount of solar radiation received at the spot where the sun is observed is lower than when the sun is high in the sky because the same amount of solar radiation is being spread over a large area. This means that the solar rays are more spread out, resulting in less intensity of radiation reaching a specific spot.

Omnivores are organisms that can consume both plants and animals. The trophic levels in an ecosystem represent the different levels of the food chain, with the first trophic level being occupied by primary producers (plants). Since omnivores can consume both plants and animals, they can exist at any trophic level, including the first trophic level. Therefore, the statement "are never found in the first trophic level" is incorrect.

The 10% rule of energy conversion efficiency does not explain why herbivores must be, on average, 10% larger than carnivores. The rule states that only about 10% of energy is transferred from one trophic level to the next, meaning that each level can only support about 10% of the biomass of the level below it. This is why herbivores biomass must exceed that of carnivores and why big, fierce animals are rare. It also suggests that 90% of what an organism eats is used in cellular respiration or lost as feces, limiting the length of the food chain.

A biome is a large geographical area characterized by distinct plant communities that are adapted to specific climatic conditions. It is not solely defined by the presence of animals or different population types, but rather by the specific types of plants that dominate the area and their relationship with the climate. The correct answer states that a biome is an area with distinct plant communities and associated with particular climates, which accurately captures the essence of a biome.