Bv Ecology Practice Test Expanded

The given statement describes the relationship between tapeworms and humans, where tapeworms live, eat, and reproduce inside the human digestive tract, robbing the host of nutrients. This is an example of parasitism, as the tapeworm benefits by obtaining nutrients from the host while the host is harmed by the loss of nutrients.

Grass is a producer because it is able to convert sunlight into energy through the process of photosynthesis. Producers are organisms that produce their own food and form the base of the food chain. In this graph, grass is the only organism listed that is capable of producing its own food, making it the correct answer.

Energy pyramids represent the flow of energy through different trophic levels in an ecosystem. Each level transfers only a fraction of the energy it receives to the next level, resulting in a decrease in available energy as we move up the pyramid. This loss of energy limits the number of levels that can be supported. By the time we reach the upper levels, there is insufficient energy to sustain a large number of organisms, hence energy pyramids are often limited to four or five levels.

Photosynthesis is the correct answer because it is the process through which carbon dioxide is converted into organic compounds, such as glucose, by green plants and some other organisms. During photosynthesis, plants use sunlight, water, and carbon dioxide to produce glucose and oxygen. This process plays a crucial role in the carbon cycle as it removes carbon dioxide from the atmosphere and converts it into organic matter, which can be consumed by other organisms or stored in plant tissues.

In a pyramid of energy, energy is transferred from one trophic level to the next higher trophic level. The transfer of energy is not efficient, and a significant amount of energy is lost as heat during each transfer. On average, about 90% of the energy is lost during this process. This means that only 10% of the energy from one trophic level is available for the next higher trophic level. This loss of energy is due to metabolic processes, heat production, and incomplete digestion and absorption of food by organisms.

All of the options listed (bacteria, fungi, small animals, humans) are subject to the limits imposed by logistic growth. Logistic growth refers to the concept that populations will eventually reach a carrying capacity, where resources become limited and growth slows down. This applies to all organisms, including bacteria, fungi, small animals, and humans. Therefore, the correct answer is that all of these options are subject to such limits.

Nitrogen comprises 78% of the atmosphere. This means that out of all the gases present in the Earth's atmosphere, nitrogen makes up the largest portion. The remaining 22% is composed of other gases such as oxygen, carbon dioxide, and trace amounts of other gases. Nitrogen is essential for various biological processes and is a key component in the formation of proteins and DNA.

An ecosystem includes all of the other levels of organization. A population refers to a group of individuals of the same species in a given area. A community refers to all the populations of different species in a given area. An organism refers to an individual living thing. A habitat refers to the specific environment where an organism lives. An ecosystem, on the other hand, includes all the living organisms (populations and communities) in an area, as well as the non-living factors (habitat) that interact with them. Therefore, the ecosystem encompasses all the other levels of organization.

The atmosphere is the greatest reserve of nitrogen on planet Earth. Nitrogen makes up about 78% of the Earth's atmosphere, making it the largest source of this element. Nitrogen is essential for various biological processes and is a key component of proteins and DNA. While nitrogen is also found in water, ground, and living organisms, the atmosphere contains the highest concentration and is therefore considered the greatest reserve.

Photosynthetic organisms, such as plants and algae, use carbon dioxide as their primary source of carbon for photosynthesis. They obtain carbon dioxide from the atmosphere and water. During photosynthesis, these organisms convert carbon dioxide into organic compounds, such as glucose, which they use as a source of energy and building blocks for growth and development. Therefore, carbon dioxide in the atmosphere and water serves as the main source of carbon for photosynthetic organisms.

A vegetarian is known as a primary consumer because they primarily consume plants and plant-based products. Primary consumers are the herbivores in a food chain or food web, which means they feed directly on producers (plants) for their energy and nutrients. Since vegetarians do not consume meat or animal products, they rely on plants as their main source of food. Therefore, the correct answer is "Primary Consumer".

Opportunistic, or r-strategy, organisms are characterized by their ability to reach sexual maturity rapidly. This means that they can reproduce at a young age and produce a large number of offspring in a short period of time. This strategy allows them to take advantage of favorable conditions and maximize their reproductive success. It is a common adaptation among species that inhabit unpredictable or unstable environments, where survival rates may be low and resources may be limited. By reaching sexual maturity quickly, these organisms can increase their chances of passing on their genes before unfavorable conditions arise.

Combustion is the process of burning fossil fuels, such as coal, oil, and natural gas, which releases carbon dioxide into the atmosphere. This is the leading cause of an increase in carbon dioxide levels in the atmosphere. Combustion occurs in various activities, including power generation, transportation, and industrial processes. As these fossil fuels are burned, the carbon stored within them is released as carbon dioxide, contributing to the greenhouse effect and climate change.

In an ecosystem, energy flow is one-way. This means that energy enters the ecosystem through the producers (plants) who convert sunlight into chemical energy through photosynthesis. This energy is then passed on to the primary consumers (herbivores) who eat the plants, and then to the secondary consumers (carnivores) who eat the herbivores. Energy is continuously transferred from one trophic level to the next, but it is not recycled back to the producers. Eventually, energy is lost as heat and is not available for further use. This unidirectional flow of energy is what sustains the ecosystem.

Photosynthesis is the process by which plants convert carbon dioxide and water into glucose and oxygen, using sunlight as the source of energy. Therefore, the correct answer is carbon, as carbon is a crucial element in the cycle of photosynthesis.

Frogs are considered secondary consumers because they feed on grasshoppers, which are primary consumers. In an ecosystem, primary consumers obtain energy by consuming producers, such as grass, while secondary consumers obtain energy by consuming primary consumers. Since frogs consume grasshoppers, they are classified as secondary consumers in this food chain.

The correct answer is "has many offspring, little care, few survive." This is because r-strategists are species that prioritize producing a large number of offspring, but provide minimal care for them. Due to the lack of parental investment, only a few of the offspring are expected to survive to adulthood. This reproductive strategy is commonly observed in species such as insects, fish, and some reptiles.

The competitive exclusion principle states that two species competing for the same resources cannot coexist indefinitely. In this scenario, the researcher combined cultures of two species of paramecium, but all individuals of one species died after 20 days. This suggests that one species outcompeted the other for resources, leading to the extinction of the less competitive species. Therefore, the correct answer is the competitive exclusion principle.

During photosynthesis, plants use sunlight, water, and carbon dioxide to produce oxygen and sugar. The process involves capturing energy from the sun and converting it into chemical energy stored in the form of sugar molecules. Oxygen is a byproduct of this process and is released into the atmosphere, while sugar is used by the plant as a source of energy for growth and other metabolic activities. Therefore, the correct answer is "Oxygen and Sugar."

In an ecosystem, energy flows in a unidirectional manner, starting from producers (plants) and passing through primary consumers (herbivores), secondary consumers (carnivores), and tertiary consumers (top carnivores). This implies that energy is not recycled within the ecosystem. Instead, it is transferred from one trophic level to another, with a significant amount being lost as heat at each level. The ultimate source of energy in an ecosystem is the sun, which is converted into chemical energy by producers through photosynthesis. Therefore, all the statements provided are true about energy in an ecosystem except for the fact that energy is recycled.

Oxygen comprises 21% of the atmosphere. This means that out of all the gases present in the Earth's atmosphere, oxygen makes up approximately one-fifth of the total composition. This is a significant percentage considering that oxygen is essential for the survival of most organisms, including humans.

The associated image depicts competitive exclusion. Competitive exclusion is a concept in ecology where two species with similar resource requirements cannot coexist in the same habitat. One species will outcompete the other, leading to the exclusion of the weaker species. The image likely shows a situation where one species has successfully outcompeted another for resources, resulting in the exclusion of the weaker species.

Based on the graph, it can be inferred that there is a direct correlation between the amount of grass and the number of sparrows in the ecosystem. Since the graph shows a single sparrow for every 100 kg of grass, it can be expected that with 100 kg of grass, there would be 1 kg of sparrows in the ecosystem.

The given answer is an example of a density-independent regulator of population growth. Density-dependent regulators are factors that affect population growth in relation to the population density, such as competition for resources, predation, and disease. In this case, the death of orange trees due to freezing temperatures is not influenced by the density of the population, but rather by the extreme environmental condition.

Resource partitioning refers to the division of limited resources among different species in order to reduce competition. In this scenario, the five closely related species of warblers have adapted to utilize different areas of the spruce tree or hunt for food in different ways. This allows them to coexist in the same habitat by minimizing competition for resources. By partitioning the resources, each species can access the necessary food sources without directly competing with one another, promoting species diversity and reducing the likelihood of extinction.

Combustion, respiration, and decomposition are all processes that increase the amount of carbon dioxide in the atmosphere. Combustion involves the burning of fossil fuels, releasing carbon dioxide as a byproduct. Respiration is the process by which organisms release carbon dioxide as they breathe. Decomposition is the breakdown of organic matter, which also releases carbon dioxide. Photosynthesis, on the other hand, is the process by which plants absorb carbon dioxide from the atmosphere, so it does not increase the amount of carbon dioxide in the atmosphere.

A climax community refers to a stable and mature ecosystem that has reached a state of equilibrium. It is characterized by a complex and diverse array of species that are well-adapted to the prevailing environmental conditions. However, if a catastrophic event, such as a wildfire or volcanic eruption, occurs, it can disrupt the balance of the climax community and lead to its replacement by another community. This is because such events can cause significant changes in the physical environment, making it unsuitable for the existing species and allowing new species to colonize and establish themselves.

Rocks and fossil fuels contain the largest reserve of carbon on planet Earth. Fossil fuels, such as coal, oil, and natural gas, are formed from the remains of ancient plants and animals that have been buried and subjected to high heat and pressure over millions of years. These fuels store carbon that was originally absorbed by plants through photosynthesis. Additionally, carbon is stored in rocks such as limestone, which is formed from the accumulation of marine organisms' remains. Therefore, rocks and fossil fuels hold a significant amount of carbon, making them the largest reserve on Earth.

Primary succession refers to the process of ecological succession that occurs in an area that has been completely devoid of life, such as new lava or sand dunes. In these harsh environments, pioneer species like lichens and mosses colonize the barren landscape, gradually breaking down rocks and creating soil. Over time, more complex plant species can establish themselves, attracting animals and leading to the development of a diverse ecosystem. This process can take hundreds or even thousands of years. Therefore, new lava or sand dunes are examples of areas where primary succession can be observed.

Respiration is the process by which cells convert oxygen and glucose/sugar into energy. Oxygen is necessary for respiration because it acts as the final electron acceptor in the electron transport chain, which generates ATP, the energy currency of cells. Glucose/sugar is the source of carbon atoms used to produce ATP through cellular respiration. Therefore, the correct answer is oxygen and glucose/sugar.

Secondary succession refers to the process of ecological succession that occurs in an area that has previously been inhabited by living organisms but has been disturbed or destroyed. In this case, the growth of weeds when a garden is tilled is an example of secondary succession. The disturbance caused by tilling the garden disrupts the existing plant community, allowing opportunistic species like weeds to colonize and establish themselves in the newly available space. Over time, the weed community may evolve and transition into a more stable and diverse plant community through further successional processes.