Natural Resources - Practice Test, Class 9 Science - Class 9 MCQ

Yes because tigers of india are only seen in corbett national park.therefore its is famous for its tigers.

Green plants of an ecosystem are called producers.
Producers are organisms that have the ability to produce their own food through the process of photosynthesis. They use sunlight, carbon dioxide, and water to synthesize glucose and oxygen. Green plants, such as trees, grasses, and algae, are examples of producers in an ecosystem. Here is a detailed explanation of why green plants are considered producers:
1. Photosynthesis: Green plants possess chlorophyll, a pigment that allows them to capture sunlight energy. Through the process of photosynthesis, they convert this energy into chemical energy in the form of glucose.
2. Autotrophs: Producers are also known as autotrophs because they can synthesize organic compounds using inorganic substances. Green plants are capable of producing their own food without relying on other organisms.
3. Primary producers: Green plants occupy the first trophic level in a food chain or food web. They are the primary source of energy in an ecosystem and provide food for other organisms.
4. Importance: Producers play a vital role in ecosystems as they provide energy and nutrients to consumers. They are responsible for converting solar energy into chemical energy, which is then transferred through the food chain.
In conclusion, green plants are called producers because they have the ability to produce their own food through photosynthesis. They are autotrophs and occupy the first trophic level in a food chain. Their role is crucial in sustaining the ecosystem by providing energy and nutrients to other organisms.

Energy flow in the ecosystem
Introduction:
Energy flow is an essential process in an ecosystem, as it determines the transfer of energy from one organism to another. It is through this energy flow that nutrients and energy are passed along the food chain, sustaining life within the ecosystem.
Unidirectional nature:
The energy flow in an ecosystem is primarily unidirectional, meaning it flows in one direction. This unidirectional flow can be explained as follows:
1. Energy input: Energy enters the ecosystem primarily from the sun, through the process of photosynthesis carried out by plants. Sunlight is converted into chemical energy in the form of glucose, which is then stored in plants.
2. Primary producers: Plants, as primary producers, convert solar energy into chemical energy through photosynthesis. They are the entry point for energy into the ecosystem.
3. Energy transfer: The energy stored in plants is then transferred to primary consumers (herbivores) when they consume plant material. This transfer of energy occurs through feeding relationships.
4. Secondary consumers: Secondary consumers, such as carnivores, obtain energy by consuming primary consumers. This energy transfer continues through successive trophic levels.
5. Energy loss: At each trophic level, energy is lost as heat during metabolic processes, such as respiration and movement. This energy loss limits the amount of energy available to the next trophic level.
6. Decomposers: Decomposers, such as bacteria and fungi, play a crucial role in the ecosystem by breaking down organic matter and releasing energy back into the environment. They complete the energy flow cycle by returning nutrients to the soil.
Conclusion:
In conclusion, energy flow in the ecosystem is primarily unidirectional, starting with the input of solar energy and progressing through the food chain. This unidirectional flow ensures the continuous transfer of energy, sustaining life within the ecosystem.

Firstly,we know that detritivores means the organisms which is heterotrophic nature in nutrition.So, Prokaryotes and fungi are two important groups of detritivores because they are also heterotrophics.

Nonrenewable Energy Source:
- Nonrenewable energy sources are those that cannot be easily replenished or regenerated within a short period of time.
- These energy sources are finite and will eventually be depleted.
Options:
- A: natural gas
- B: solar energy
- C: wind energy
- D: tidal energy
Identifying the Nonrenewable Energy Source:
- Among the given options, the nonrenewable energy source is natural gas (option A).
Explanation:
- Natural gas is considered a nonrenewable energy source because it is formed over millions of years from the remains of plants and animals buried deep within the Earth's crust.
- The extraction and production of natural gas involve drilling into underground reservoirs to release the gas.
- Once extracted, natural gas can be used for various purposes, such as heating, electricity generation, and as a fuel for vehicles.
- However, the reserves of natural gas are limited and will eventually be depleted.
- Unlike renewable energy sources, such as solar energy, wind energy, and tidal energy, natural gas cannot be replenished within a short period of time.
Therefore, the correct answer is A: natural gas.

They are primary consumers, as they do not make their own food as plants and cyanobacteria do. They must eat something in the environment. Some eat phytoplankton (the primary producers), some eat other zooplankton, some are detritivores (you could call those decomposers I guess), and others have symbiotic relationships with plants and other producers, but all must eat something in their environment, and are a food source for many other animals. They are the first level of consumers in their enviornments’ food web(s).

Terracing and Soil Conservation
Terracing is an effective soil conservation technique that involves creating flat or gently sloping platforms on hilly or steep terrain. This method helps to prevent erosion by reducing the velocity of water runoff and allowing it to infiltrate into the soil. While terracing can be beneficial in various landscapes, it is particularly helpful in hill regions.
Reasons why terracing helps the most in hill regions:
- Steep slopes: Hill regions often have steep slopes, which increase the risk of soil erosion. Terracing helps to create level surfaces that slow down the flow of water, reducing erosion.
- Water management: Terraces can effectively manage water runoff by controlling its flow, preventing it from washing away the topsoil. This is crucial in hill regions where rainfall is often intense and can easily cause erosion.
- Soil conservation: By reducing erosion, terracing helps to preserve the fertile topsoil in hill regions. This is important for agriculture and sustaining vegetation cover.
- Preventing landslides: Terraces can stabilize the soil on steep slopes, reducing the risk of landslides. They help to hold the soil in place and prevent it from slipping downhill.
- Increase agricultural productivity: Terracing creates flat or gently sloping areas that are suitable for cultivation. This allows farmers in hill regions to maximize their land use and increase agricultural productivity.
In conclusion, terracing is an effective soil conservation measure that is particularly beneficial in hill regions. It helps to control erosion, manage water runoff, stabilize slopes, preserve topsoil, and increase agricultural productivity. By implementing terracing techniques, hill regions can mitigate the negative impacts of erosion and sustain their soil resources for long-term sustainability.

As we know that tertiary consumers eat primary and secondary consumers as their main source of food (producers level). Today due to overpopulation , deforestation,lack of food and environmental pollution affects the life of producers, primary, secondary level.Thus tertiary level also most affects from this.So, Tertiary level is considered to be the most vulnerable to extinction.

Ozone Layer Location
The ozone layer is located in the stratosphere of the Earth's atmosphere. Here is a detailed explanation:
1. Atmosphere Layers:
- The Earth's atmosphere is divided into several layers based on temperature changes with altitude.
- The layers, from closest to Earth's surface to farthest, are troposphere, stratosphere, mesosphere, thermosphere, and exosphere.
2. Ozone Layer:
- The ozone layer is a region within the stratosphere that contains a high concentration of ozone (O3) molecules.
- Ozone is a form of oxygen (O2) that has three atoms instead of two.
- It is responsible for absorbing the majority of the Sun's ultraviolet (UV) radiation, protecting life on Earth from harmful UV rays.
3. Stratosphere:
- The stratosphere is located above the troposphere, extending from approximately 10 kilometers (6 miles) to 50 kilometers (31 miles) above the Earth's surface.
- It is characterized by a temperature inversion, where the temperature increases with altitude due to the presence of ozone.
4. Ozone Production and Destruction:
- Ozone is naturally produced in the stratosphere through the interaction of ultraviolet radiation with oxygen molecules.
- However, human activities, such as the release of certain chemicals called ozone-depleting substances (ODS), can accelerate the destruction of ozone molecules.
- The most well-known ODS are chlorofluorocarbons (CFCs) which were commonly used in aerosol cans, refrigeration systems, and air conditioning units.
5. Importance of the Ozone Layer:
- The ozone layer plays a crucial role in protecting life on Earth by absorbing most of the Sun's harmful UV-B and UV-C radiation.
- Excessive exposure to UV radiation can lead to various health issues, including skin cancer, cataracts, and weakened immune system.
- The depletion of the ozone layer can also have detrimental effects on ecosystems, including the disruption of marine and terrestrial food chains.
In conclusion, the ozone layer is located in the stratosphere, which is the second layer of Earth's atmosphere. It is responsible for absorbing harmful UV radiation and plays a vital role in protecting life on Earth.

Solar radiations heat up:
A: Land faster than the water bodies
- Land absorbs solar radiation more efficiently than water due to its lower specific heat capacity.
- Land has a lower albedo (reflectivity) compared to water, which means it absorbs a greater amount of solar radiation.
- The surface of the land is often rough and uneven, allowing for better absorption and retention of heat.
- Land heats up faster during the day as it requires less energy to raise its temperature compared to water.
B: Land slower than the water bodies
- This statement is incorrect as land heats up faster than water bodies.
C: Equally both land and water bodies
- This statement is incorrect as land heats up faster than water bodies.
D: Neither land nor water bodies
- This statement is incorrect as both land and water bodies are heated by solar radiation.
In conclusion, solar radiations heat up land faster than water bodies due to land's lower specific heat capacity, higher absorption rate, lower albedo, and rougher surface.

Non-Renewable Resources:
Non-renewable resources are those natural resources that cannot be replenished or regenerated within a short period of time. These resources are finite in nature and their availability diminishes over time. One example of non-renewable resources is coal and minerals.
Coal and Minerals:
- Coal is a fossil fuel formed from the remains of plants that lived and died millions of years ago. It is extracted from underground mines and used primarily for electricity generation and industrial purposes.
- Minerals are naturally occurring inorganic substances found in the Earth's crust. They are used in various industries such as construction, manufacturing, and electronics.
Characteristics of Coal and Minerals:
- Limited Availability: Coal and minerals are finite resources and their reserves are depleting over time. Once extracted and used, they cannot be replaced.
- Extraction Process: Coal and minerals require extensive mining operations to extract them from the Earth's crust. These processes can have significant environmental impacts, including habitat destruction and pollution.
- Energy Source: Coal is a major source of energy worldwide, but its combustion releases carbon dioxide and other pollutants, contributing to air pollution and climate change.
- Economic Importance: Coal and minerals play a vital role in the economy, providing raw materials for various industries and supporting employment opportunities.
Conclusion:
Coal and minerals are examples of non-renewable resources due to their limited availability, extensive extraction processes, and environmental impacts. It is important to explore alternative sources of energy and promote sustainable practices to reduce reliance on non-renewable resources and mitigate their negative effects on the environment.

Renewable Resources:
- Renewable resources are resources that can be replenished or regenerated naturally over a short period of time.
- They are considered sustainable as they are not depleted or consumed at a faster rate than they can be renewed.
- Examples of renewable resources include soil, water, flora, and fauna.
Analysis of the options:
- A: Soil
- Soil is a renewable resource as it can be replenished through natural processes such as decomposition and weathering.
- It takes time for soil to form, but with proper land management and conservation practices, it can be renewed and sustained.
- B: Water
- Water is also a renewable resource as it undergoes the water cycle, where it evaporates, condenses, and precipitates back to the Earth's surface.
- This process replenishes the water sources and ensures its availability.
- C: Flora and fauna
- Flora and fauna refer to the plant and animal life, respectively.
- They are renewable resources as they have the ability to reproduce and regenerate naturally.
- With proper conservation efforts and sustainable practices, the flora and fauna can be sustained.
Conclusion:
- Based on the analysis, all the options mentioned (A, B, and C) are renewable resources.
- Therefore, the correct answer is option D: All the above.

Protection provided by Ozone in the stratosphere:
The ozone layer in the stratosphere plays a crucial role in protecting life on Earth. Here's a detailed explanation of how ozone provides protection:
1. Absorption of UV radiation:
- Ozone molecules absorb and filter out most of the Sun's harmful ultraviolet (UV) radiation.
- The ozone layer acts as a shield, preventing the majority of UV-B (medium wavelength) and UV-C (short wavelength) radiation from reaching the Earth's surface.
2. Protection from skin cancer:
- UV radiation, particularly UV-B, is known to cause skin cancer in humans.
- The ozone layer's absorption of UV-B radiation reduces the risk of skin cancer and related health issues.
3. Preservation of ecosystems:
- UV radiation can have damaging effects on plants, phytoplankton, and other organisms in aquatic ecosystems.
- The ozone layer protects these ecosystems by reducing the penetration of harmful UV radiation into the water, ensuring the well-being of various species.
4. Safeguarding of the food chain:
- Ozone depletion can affect the productivity of phytoplankton, which forms the base of the marine food chain.
- By shielding phytoplankton from excessive UV radiation, the ozone layer helps maintain the balance of marine ecosystems and the abundance of marine life.
5. Climate regulation:
- Ozone indirectly contributes to climate regulation by influencing the distribution of solar energy in the Earth's atmosphere.
- The absorption of UV radiation by ozone affects temperature patterns and atmospheric circulation, which in turn impact weather and climate.
In conclusion, the ozone layer, primarily composed of ozone (O3) molecules, provides essential protection to life on Earth by absorbing and filtering out harmful UV radiation from the Sun. This protection is crucial for human health, the preservation of ecosystems, the stability of the food chain, and climate regulation.

The life supporting gases such as O2, CO2, and N2 are chiefly concentrated in the troposphere.
The troposphere is the lowest layer of the Earth's atmosphere, extending from the surface up to an average height of about 8-15 kilometers (5-9 miles). It is where weather phenomena occur and where most of the Earth's air mass is found. Here's why the correct answer is A:
1. Troposphere:
- The troposphere is the layer closest to the Earth's surface and is responsible for the majority of the Earth's weather.
- It contains about 75-80% of the total mass of the Earth's atmosphere.
- This layer is where we live and breathe, and it is where the life supporting gases such as oxygen (O2), carbon dioxide (CO2), and nitrogen (N2) are concentrated.
2. Exosphere:
- The exosphere is the outermost layer of the Earth's atmosphere, located above the thermosphere.
- It is a transitional region between Earth's atmosphere and outer space.
- The gases in the exosphere are very sparse, and the concentration of life supporting gases is negligible. Therefore, it is not the chief concentration of these gases.
3. Homosphere:
- The homosphere refers to the region of the atmosphere where the composition of gases is relatively uniform throughout.
- In the homosphere, the gases are well mixed and evenly distributed.
- While the homosphere includes the troposphere, it also extends into the upper layers of the atmosphere. Therefore, it is not solely responsible for the chief concentration of life supporting gases.
4. Stratosphere:
- The stratosphere is the layer above the troposphere, extending from about 15-50 kilometers (9-31 miles) above the Earth's surface.
- It is characterized by the presence of the ozone layer, which absorbs most of the Sun's harmful ultraviolet radiation.
- While the stratosphere contains a small amount of life supporting gases, its chief concentration is not as significant as in the troposphere.
In conclusion, the life supporting gases such as O2, CO2, and N2 are chiefly concentrated in the troposphere, which is the layer closest to the Earth's surface and where most of the Earth's air mass is found.

The Best Soil for Plant Growth: Loamy Soil
Loamy soil is widely considered the best soil for plant growth due to its balanced composition and excellent drainage capabilities. Here's a detailed explanation:
1. Composition:
- Loamy soil is a mixture of sand, silt, and clay in relatively equal proportions.
- It contains a good balance of both large and small particles, which allows for proper aeration, water retention, and nutrient availability.
- The presence of organic matter in loamy soil further enhances its fertility and nutrient-holding capacity.
2. Drainage:
- Loamy soil has excellent drainage capabilities, meaning it allows water to flow through it easily without becoming waterlogged.
- This is important for plant growth as excessive moisture can lead to root rot and other diseases.
- At the same time, loamy soil retains enough moisture to keep plants hydrated during dry spells, making it ideal for a wide range of plant species.
3. Nutrient Availability:
- Loamy soil has a high nutrient-holding capacity, allowing plants to access essential minerals and trace elements.
- The balanced composition of loamy soil ensures that nutrients are not excessively leached away by water or rendered unavailable due to compaction.
4. Root Development:
- The loose and crumbly texture of loamy soil provides an ideal environment for root development.
- Plant roots can easily penetrate the soil, accessing both water and nutrients without encountering excessive resistance.
- This promotes healthy root growth, leading to stronger and more productive plants.
In conclusion, loamy soil is the best choice for plant growth due to its balanced composition, excellent drainage, nutrient availability, and optimal root development conditions. It provides a favorable environment for a wide range of plant species to thrive and produce abundant yields.

Answer: C. Biogas plants
Explanation:
Biogas plants are the source of both power and manure. Here's a detailed explanation:
1. Biogas Plants:
- Biogas plants are facilities that utilize organic waste materials, such as agricultural waste, food waste, or animal manure, to produce biogas.
- These plants typically consist of anaerobic digesters, where the organic waste is broken down by bacteria in the absence of oxygen.
- The byproduct of this process is biogas, which primarily consists of methane and carbon dioxide.
2. Power Generation:
- Biogas can be used as a fuel to generate electricity and heat.
- The biogas is combusted in a gas turbine or a reciprocating engine, which drives a generator to produce electricity.
- This electricity can be utilized for various purposes, including powering homes, businesses, and even entire communities.
3. Manure Production:
- As part of the anaerobic digestion process, the organic waste is transformed into a nutrient-rich byproduct known as digestate.
- Digestate is a type of manure that can be used as a natural fertilizer in agriculture.
- It contains essential nutrients like nitrogen, phosphorus, and potassium, which are beneficial for plant growth and soil health.
4. Benefits of Biogas Plants:
- Biogas plants provide a sustainable solution for waste management by converting organic waste into useful resources.
- The production of biogas reduces the emission of greenhouse gases, such as methane, which is a potent contributor to climate change.
- The generated electricity can help reduce reliance on fossil fuels, leading to a cleaner and more sustainable energy system.
- The use of digestate as fertilizer reduces the need for chemical fertilizers, promoting organic farming practices and minimizing environmental pollution.
Therefore, biogas plants play a crucial role in providing both power and manure, making them a valuable asset for sustainable energy and waste management.

The Major Raw Material for Biogas is Cow Dung

• Biogas: Biogas is a renewable energy source produced through the process of anaerobic digestion.


• Raw Material: The raw material used in the production of biogas is known as the substrate or feedstock.


• Cow Dung: Cow dung is the major raw material for biogas production.


• Composition: Cow dung is rich in organic matter and contains a high concentration of volatile solids.


• Anaerobic Digestion: The process of anaerobic digestion involves the breakdown of organic matter by bacteria in the absence of oxygen.


• Bacteria: The bacteria present in cow dung convert the organic matter into biogas through a series of biochemical reactions.


• Other Feedstocks: Although cow dung is the major raw material, other organic materials such as agricultural residues, food waste, and sewage sludge can also be used as feedstock for biogas production.


• Benefits: The use of cow dung as a raw material for biogas production has various benefits, including waste management, energy generation, and reduction of greenhouse gas emissions.

Therefore, cow dung is the preferred raw material for biogas production due to its availability, high organic content, and potential for sustainable energy generation.

Atomic energy is obtained by using ores of uranium.

Here is a detailed explanation:

• Atomic energy: Atomic energy refers to the energy released by the process of nuclear reactions, specifically nuclear fission or fusion. It is a form of energy that is generated by manipulating the structure of atoms.


• Uranium: Uranium is a naturally occurring radioactive element that is commonly used as a fuel in nuclear power plants.


• Ores of uranium: Uranium is primarily obtained from its ores, which are rocks or minerals that contain a high concentration of uranium. The most commonly used uranium ore is uranium oxide, also known as pitchblende.


• Process of obtaining atomic energy: Atomic energy is obtained through the process of nuclear fission, where the nucleus of an atom is split into two smaller nuclei, releasing a significant amount of energy. Uranium-235, a radioactive isotope of uranium, is commonly used in nuclear reactors for this purpose.


• Role of uranium: Uranium-235 is a fissile material, which means it can sustain a nuclear chain reaction. When uranium-235 absorbs a neutron, it becomes unstable and splits into two smaller nuclei, along with the release of additional neutrons and a large amount of energy.


• Usage of atomic energy: Atomic energy generated from uranium is used to produce electricity in nuclear power plants, as well as for various other applications such as propulsion in nuclear submarines and spacecraft, and in medical and industrial fields.

Therefore, the correct answer is B: uranium. Uranium ores are used to obtain atomic energy through the process of nuclear fission.

Sanctuaries are established to protect animals.
- Definition: A sanctuary is a place where animals are protected and given a safe environment to live in.
- Purpose: The main objective of establishing sanctuaries is to protect and conserve the biodiversity of a particular area and provide a safe haven for wildlife.
- Habitat preservation: Sanctuaries help in preserving natural habitats for animals by providing them with suitable living conditions, food, and water sources.
- Conservation of endangered species: Many sanctuaries focus on conserving and protecting endangered species, providing a safe space for them to breed and thrive.
- Protection from hunting and poaching: Sanctuaries play a crucial role in protecting animals from illegal hunting, poaching, and other forms of exploitation.
- Research and education: Sanctuaries often serve as research centers for studying animal behavior, ecology, and conservation. They also play a vital role in educating the public about the importance of wildlife conservation.
- Rehabilitation and release: Some sanctuaries rehabilitate injured or orphaned animals and then release them back into the wild once they are ready.
- Ecotourism: Sanctuaries can also attract tourists who are interested in observing and learning about wildlife, thus contributing to the local economy and raising awareness about conservation efforts.
In summary, sanctuaries are established primarily to protect and conserve animals, providing them with a safe environment to live in and ensuring their survival for future generations.

As we know that fossil fuels means the fuel which is the sources of energy that have developed within the earth over millions of years due to the decomposition of the remains of plants and animals .So,here coal, petroleum and natural gas is the example of fossil fuel.