Science Test 1 (2011)

Organisms need energy to carry out various biological processes such as growth, reproduction, movement, and maintenance of their internal environment. This energy is obtained through various metabolic processes like respiration or photosynthesis. Without energy, organisms would not be able to survive or function properly, making the statement "Organisms need energy to live" true.

Burning large amounts of coal, oil, and other fossil fuels releases carbon dioxide into the atmosphere. This is because fossil fuels are made up of carbon compounds, and when they are burned, the carbon combines with oxygen to form carbon dioxide. As a result, the levels of carbon dioxide in the atmosphere increase, contributing to the greenhouse effect and climate change. Therefore, the statement is true.

Food is a source of energy for our bodies. When we consume food, it gets broken down into molecules that our body can use for energy. These molecules are then converted into ATP (adenosine triphosphate), which is the main energy currency of cells. So, it is correct to say that energy is stored in food.

Changes to ecosystems can cause a species to become extinct because ecosystems provide the necessary resources and conditions for a species' survival. Any alteration to the ecosystem, such as habitat destruction, pollution, or climate change, can disrupt the balance and availability of resources, making it difficult or impossible for a species to thrive. As a result, the species may not be able to adapt or find suitable conditions to survive, leading to their extinction. This highlights the interconnectedness and vulnerability of species within ecosystems.

Deserts are characterized by extremely low levels of rainfall, resulting in arid and dry conditions. As a result, the soil in deserts lacks vegetation cover, making it predominantly bare. This is due to the scarcity of water, which limits the growth of plants and prevents the formation of a dense plant cover. Therefore, the statement that deserts receive very little rain and much of the soil is bare is true.

Deciduous forests are characterized by receiving less rainfall compared to rainforests, and they also experience distinct warm and cold seasons. This means that the statement is accurate and true.

A niche refers to the specific role or position that a particular organism occupies within its ecosystem. It is the unique way in which an organism fits into its environment, including its interactions with other species and its utilization of resources. Each organism has its own niche, which helps to maintain the balance and functionality of the ecosystem. By occupying different niches, organisms can minimize competition for resources and coexist harmoniously. Therefore, the correct answer is niche.

Bacteria, fungi, and single-celled organisms are decomposers. Decomposers are organisms that break down dead organic matter, such as dead plants and animals, into simpler substances. They play a crucial role in nutrient recycling and the decomposition process, helping to release nutrients back into the ecosystem. By breaking down organic matter, decomposers contribute to the overall health and balance of ecosystems.

Loss of habitat causes most extinctions, meaning less babies.

The correct answer is "cold, warm, hot" because temperature is a measure of the degree of heat or coldness of an object or environment. It can be described as cold when it is at a low temperature, warm when it is at a moderate temperature, and hot when it is at a high temperature. These terms are commonly used to indicate different levels of temperature and are widely understood.

It is the loss of the last member of the species

The statement is false because deserts generally receive less rainfall compared to grasslands. Deserts are characterized by their arid and dry climate, with very little precipitation. On the other hand, grasslands receive a moderate amount of rainfall, making them more suitable for the growth of grass and other vegetation.

Freshwater refers to water that contains low levels of salt and is not found in the ocean or other saltwater bodies. It is typically found in lakes, rivers, streams, marshes, and swamps. These are all examples of freshwater ecosystems where plants and animals have adapted to survive in a freshwater environment. Forests, deserts, grasslands, oceans, coral reefs, and kelp forests, on the other hand, are not typically associated with freshwater environments.

Ecosystems are constantly changing due to various factors such as natural disturbances, climate change, human activities, and the interactions between different species. These changes can include shifts in species composition, population sizes, and overall ecosystem structure and function. It is important to understand and monitor these changes to effectively manage and conserve ecosystems and the services they provide. Therefore, the statement "Ecosystems are constantly changing" is true.

Ecosystems are indeed divided into two categories: nonliving and living. This division is based on the components that make up an ecosystem. The nonliving category includes factors such as climate, soil, water, and sunlight, which provide the necessary physical and chemical conditions for life. On the other hand, the living category includes all the organisms that inhabit the ecosystem, including plants, animals, and microorganisms. Both these categories are essential for the functioning and balance of an ecosystem.

Saltwater refers to water that has a high concentration of salt, typically found in oceans, coral reefs, and kelp forests. These environments are characterized by their saline nature and are home to a wide variety of marine organisms adapted to live in such conditions. The presence of saltwater in these ecosystems creates a unique habitat that supports diverse marine life and plays a crucial role in the overall health of the planet's oceans.

Introduced species can have a negative impact on local populations and ecosystems. When a species is introduced into a new ecosystem, it can outcompete native species for resources such as food, water, and habitat, leading to the decline or extinction of local populations. This can disrupt the balance of the ecosystem and cause further cascading effects on other species and the overall ecosystem health. Therefore, it is true that introduced species can cause the extinction of local populations.

A decomposer refers to an organism that feeds on dead producers and consumers, playing a crucial role in the ecosystem by breaking down organic matter and returning nutrients to the soil. Decomposers, such as bacteria and fungi, help in the process of decomposition, which is an essential part of the nutrient cycle. They break down dead organisms into simpler substances, allowing the nutrients to be recycled and reused by other organisms.

Scorpions, coyotes, and roadrunners are all organisms that have adapted to survive in desert environments. Deserts are characterized by extreme temperatures, limited water availability, and sparse vegetation. Scorpions have evolved to withstand the arid conditions and can go for long periods without water. Coyotes have adapted to the lack of water by obtaining moisture from their prey and are able to regulate their body temperature in the harsh desert climate. Roadrunners have developed long legs for running in the open desert and have specialized beaks for catching prey. Therefore, it is logical to conclude that these animals live in deserts.

Terrestrial refers to land-based ecosystems, excluding bodies of water. Forests, deserts, and grasslands are examples of terrestrial environments as they are all located on land. These ecosystems are characterized by their distinct vegetation and wildlife, with forests being dominated by trees, deserts having sparse vegetation and extreme arid conditions, and grasslands consisting mainly of grasses.

The statement is true because the burning of fossil fuels such as coal and oil releases greenhouse gases, including carbon dioxide, into the atmosphere. These greenhouse gases trap heat from the sun, leading to an increase in global temperatures and causing global warming. Therefore, the large amount of fossil fuels being released into the atmosphere is contributing to global warming.

Gazelles, zebras, and lions are commonly found in grasslands, specifically in Africa. Grasslands provide the ideal habitat for these animals as they offer an abundance of grasses and open spaces for grazing, as well as opportunities for hunting and predation. The African grasslands, also known as savannas, are characterized by vast expanses of grasses, scattered trees, and a diverse range of wildlife. This ecosystem supports the coexistence of herbivores like gazelles and zebras, as well as predators like lions, making it the most suitable option among the given choices.

Carnivores are organisms that primarily consume other animals. In the given food chain, carnivores are positioned after herbivores, indicating that they feed on herbivores. This means that they obtain their energy and nutrients by consuming other animals.

The given answer, "food chains," is the correct explanation for the definition provided. Food chains refer to the sequence of organisms in an ecosystem where energy is transferred from one organism to another through the consumption of food. It starts with the producers, which convert sunlight into energy through photosynthesis. The energy is then passed on to the herbivores, who consume the producers. Carnivores and omnivores come next in the food chain, as they consume the herbivores or other organisms. Therefore, food chains accurately describe how food energy moves from one organism to another in a community.

The statement is true because taiga is indeed a type of forested land that is characterized by the presence of evergreen trees such as pine, fir, and spruce. The taiga biome is typically found in cold climates, particularly in the northern parts of North America, Europe, and Asia. The evergreen trees in the taiga are well-adapted to survive the long, harsh winters and have needle-like leaves that help them conserve water. Overall, the statement accurately describes the characteristics of the taiga biome.

Grasslands receive less rainfall than forests because they are characterized by a dry climate and have shorter growing seasons. The lack of dense tree cover in grasslands allows for more sunlight to penetrate the ground, leading to higher evaporation rates and less moisture retention. This results in less rainfall in grasslands compared to forests, which have a higher amount of precipitation due to the presence of trees that can capture and retain moisture.

The given answer, "Biomes," is correct because the question is asking for the term that describes the different types of ecosystems found on Earth. Biomes are large areas with distinct climate, vegetation, and animal life. The options "Global Warming" and "Permafrost" are not appropriate answers as they do not refer to the different types of ecosystems.

Monkeys, sloths, orchids, and parrots are all species that are typically found in tropical rainforests. These ecosystems provide the ideal conditions for these organisms to thrive, with their high temperatures, abundant rainfall, and dense vegetation. The other options, such as deciduous forests, grasslands, deserts, taiga, and tundra, do not offer the same suitable habitat for these specific species. Therefore, the correct answer is tropical rainforest.

When plants and animals die, other bacteria break down their bodies through a process called decomposition. During this process, the bacteria release nitrogen gas back into the air. This is a crucial step in the nitrogen cycle, where nitrogen is continuously converted between different forms to be used by various organisms. Nitrogen gas is an essential component of the Earth's atmosphere and is necessary for the growth and survival of living organisms.

Herbivores are the correct answer because they are the animals that eat only plants. In the given food chain, the producers are the first level, followed by the second level producers. Herbivores, which are animals that feed on plants, come next in the chain. Carnivores, which are animals that eat other animals, and omnivores, which are animals that eat both plants and animals, are not the correct answer as they do not exclusively eat plants.

The answer includes three different soil conditions: run off or erosion, drought, and mud. Run off or erosion refers to the process of water carrying away soil particles, which can lead to soil degradation. Drought indicates a lack of water in the soil, causing it to become dry and potentially impacting plant growth. Mud refers to soil that is saturated with water, resulting in a soft and wet consistency. These three conditions highlight the different challenges and characteristics that can be present in soil.

Carbon dioxide and oxygen move between living and nonliving parts of an ecosystem in the carbon dioxide-oxygen cycle. This cycle involves the process of photosynthesis, where plants take in carbon dioxide from the atmosphere and release oxygen as a byproduct. Then, during respiration, living organisms take in oxygen and release carbon dioxide. This exchange of gases between living organisms and the environment ensures a continuous supply of oxygen for organisms to breathe and a source of carbon dioxide for plants to perform photosynthesis.

Single-celled algae are capable of photosynthesis, which means they can convert sunlight, carbon dioxide, and water into glucose (food) and oxygen. This process allows them to produce their own food and energy, making them producers in the ecosystem. Producers are organisms that can synthesize their own organic compounds and form the base of the food chain by providing energy to other organisms.

The nitrogen cycle describes how nitrogen moves between living and nonliving parts of an ecosystem. This cycle involves various processes such as nitrogen fixation, nitrification, assimilation, ammonification, and denitrification. Bacteria play a crucial role in this cycle by converting atmospheric nitrogen into a form that can be used by plants. Plants then take up this nitrogen and incorporate it into their tissues. Animals obtain nitrogen by consuming plants or other animals. Decomposers break down dead organisms and release nitrogen back into the soil, completing the cycle.

A producer is an organism that is able to make its own food through the process of photosynthesis or chemosynthesis. They are typically plants or algae that use sunlight, carbon dioxide, and water to produce glucose and oxygen. This ability to produce their own food allows producers to occupy the first trophic level in a food chain or web, and they form the foundation of all ecosystems.

Ecology is the correct answer because it is defined as the study of how the living and nonliving parts of ecosystems work together. It focuses on the relationships between organisms and their environment, including the interactions between different species, populations, and communities. Ecology also examines the physical and chemical factors that influence the distribution and abundance of organisms within their habitats. Therefore, ecology encompasses the study of ecosystems and their functioning, making it the most appropriate term among the given options.

Prairie dogs, elk, and buffalo are known to inhabit grasslands, particularly in North America. Grasslands provide the ideal habitat for these animals as they offer open spaces with abundant grass for grazing. The climate and vegetation of North American grasslands are well-suited for these species, allowing them to thrive in this ecosystem.

An organism refers to an individual living thing that is capable of carrying out the basic functions of life, such as growth, reproduction, and response to stimuli. It can be a plant, animal, or microorganism. In the context of the given definitions, all the other terms (ecosystem, ecology, species, population, community, and habitat) are related to the study or understanding of organisms and their interactions with the environment. Therefore, organism is the correct answer as it directly refers to a living thing itself.

The first producer in a food chain refers to the organism that directly converts sunlight into energy through the process of photosynthesis. This organism is typically a plant or algae that uses sunlight, water, and carbon dioxide to produce glucose and oxygen. As the main producer in the food chain, it serves as the primary source of energy for all other organisms in the ecosystem.

Omnivores are organisms that consume both plants and animals as their source of food. In the given food chain, omnivores are positioned at the top, indicating that they are capable of consuming both herbivores and carnivores. This suggests that they have a wider range of food options compared to herbivores and carnivores, allowing them to adapt to different environments and obtain nutrients from a variety of sources.

This statement is false because plants in grasslands are adapted to survive droughts and hot summers. Grasslands are characterized by their dry and hot climate, and the plants that grow in these regions have evolved to withstand these conditions. They have deep root systems that allow them to access water from lower soil layers, and they also have adaptations such as waxy leaves or the ability to go dormant during periods of extreme heat or drought. Therefore, plants in grasslands are well-suited to survive and thrive in these challenging environmental conditions.

Woodpeckers, skunks, and deer are all examples of animals that are commonly found in deciduous forests. Deciduous forests are characterized by trees that shed their leaves seasonally, and they provide a suitable habitat for a variety of wildlife. These forests have a moderate climate with distinct seasons, which makes them ideal for these animals to thrive. Woodpeckers can find plenty of trees to excavate for food and nesting, skunks can find shelter in the forest floor, and deer can find ample vegetation to graze on. Therefore, it is logical to conclude that woodpeckers, skunks, and deer live in deciduous forests.

The statement in the question is incorrect. Global warming is not caused by the large amount of heat released in the atmosphere by trash. Global warming is primarily caused by the increase in greenhouse gases, such as carbon dioxide, in the atmosphere due to human activities like burning fossil fuels and deforestation. Trash can contribute to global warming indirectly through the release of methane gas from decomposing organic waste in landfills, but it is not the main cause. Therefore, the correct answer is False.

underneath layer of soil

An ecosystem refers to the living and nonliving parts of the environment in a particular area. It includes all the plants, animals, and microorganisms, as well as the physical elements such as air, water, and soil. The interactions between these components create a complex web of relationships and energy flows. Ecosystems can vary in size, from a small pond to a vast forest. They play a crucial role in maintaining the balance of nature and providing essential services such as water purification, nutrient cycling, and habitat for various species.

Lemmings, snowy owls, and arctic foxes are all examples of animals that are adapted to live in the tundra. The tundra is a cold and treeless biome found in the Arctic and Antarctic regions, characterized by low temperatures, permafrost, and a short growing season. These animals have specific adaptations that allow them to survive in this harsh environment, such as thick fur, small ears, and hibernation. Therefore, the correct answer is tundra.

The correct answer is "hard, constant, light". This answer seems to be describing the different types or characteristics of rainfall. "Hard" suggests that the rainfall is heavy or intense, "constant" indicates that it is continuous or consistent, and "light" implies that it is gentle or not heavy. These terms help to describe the intensity and duration of rainfall.

Taiga is found outside the arctic circle.

The given answer, "2nd Producer," refers to the position of the organism in the food chain. In a food chain, producers are the organisms that can produce their own food through photosynthesis, such as plants. They are the first level in the food chain. The 2nd Producer indicates that it is the second level in the food chain, which means it consumes the producers (plants) and is consumed by other organisms like herbivores or carnivores.

A species is a group of organisms that can mate to produce offspring like themselves. This definition highlights the reproductive compatibility and genetic similarity among individuals within a species. It distinguishes species from other ecological terms like ecosystem, ecology, population, community, habitat, and organism, which may refer to broader or more specific concepts within the study of biology and ecology.