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All questions of People and the Environment for Grade 8 Exam
Which of the following is biodegradable?- a)Plastic mugs
- b)Leather belts
- c)Silver foil
- d)Iron nails
Correct answer is option 'B'. Can you explain this answer?
Which of the following is biodegradable?
a)
Plastic mugs
b)
Leather belts
c)
Silver foil
d)
Iron nails
|
Raghav Bansal answered |
Leather belts are biodegradable whereas silver foils, plastic mugs and iron nails are non - biodegradable. It takes leather between 25-50 years to completely decompose.
Flow of energy in an ecosystem is always- a)unidirectional
- b)bidirectional
- c)multidirectional
- d)no specific direction
Correct answer is option 'A'. Can you explain this answer?
Flow of energy in an ecosystem is always
a)
unidirectional
b)
bidirectional
c)
multidirectional
d)
no specific direction
|
|
Aishwarya jain answered |
Energy flows only in one direction in an ecosystem.
Which of the following groups does not contain only biodegradable items ?- a)Grass, flowers and leather
- b)Grass, wood and plastic
- c)Fruit-peels, cake and lime juice
- d)Cake, wood and grass
Correct answer is option 'B'. Can you explain this answer?
Which of the following groups does not contain only biodegradable items ?
a)
Grass, flowers and leather
b)
Grass, wood and plastic
c)
Fruit-peels, cake and lime juice
d)
Cake, wood and grass
|
Amit Kumar answered |
Correct Answer :- b
Explanation : A Non-Biodegradable material can be defined as a kind of substance which cannot be broken down by natural organisms and acts as a source of pollution. ... Non-biodegradable wastes are those who cannot be decomposed or dissolved by natural agents.
Plastic is a non-biodegradable substance.
Which of the following limits the number of trophic levels in a food chain ?- a)Decrease in energy at higher levels
- b)Deficient food supply
- c)Polluted air
- d)Water
Correct answer is option 'A'. Can you explain this answer?
Which of the following limits the number of trophic levels in a food chain ?
a)
Decrease in energy at higher levels
b)
Deficient food supply
c)
Polluted air
d)
Water
|
|
Ananya Das answered |
Due to the 10% rule, there is a decrease in energy at every higher trophic level.
Which of the following is non-biodegradable?- a)Wool
- b)Nylon
- c)Animal bones
- d)Tea leaves
Correct answer is option 'B'. Can you explain this answer?
Which of the following is non-biodegradable?
a)
Wool
b)
Nylon
c)
Animal bones
d)
Tea leaves
|
Srishti Singh answered |
Nylon plastic is the name for a long-chain, fiber forming polyamides, composing one of the largest groups of synthetic polymers. These chains are naturally very resistant to wear and tear, temperature and chemicals.so its non biodegradable.
Which of the following are environmental-friendly practices ?- a)Carrying the cloth bags to put purchases in while shopping
- b)Switching off unnecessary lights
- c)Walking to school instead of getting your mother to drop you on her scooter
- d)All of the above
Correct answer is option 'D'. Can you explain this answer?
Which of the following are environmental-friendly practices ?
a)
Carrying the cloth bags to put purchases in while shopping
b)
Switching off unnecessary lights
c)
Walking to school instead of getting your mother to drop you on her scooter
d)
All of the above
|
|
Ananya Das answered |
All the practices mentioned are environment friendly
Trophic level in an ecosystem represents- a)oxygen level
- b)water level
- c)energy level
- d)salt level
Correct answer is option 'C'. Can you explain this answer?
Trophic level in an ecosystem represents
a)
oxygen level
b)
water level
c)
energy level
d)
salt level
|
|
Amit Sharma answered |
- Organisms occupy a place in the natural surroundings or in a community according to their feeding relationship with other organisms.
- Based on the source of their nutrition or food, organisms occupy a specific place in the food chain that is known as their trophic level.
- Producers belong to the first trophic level, herbivores (primary consumer) to the second and carnivores (secondary consumer) to the third.
- The amount of energy decreases at successive trophic levels
Hence, trophic levels represent energy level as well.
In an ecosystem, herbivores represent- a)producers
- b)primary consumers
- c)secondary consumers
- d)decomposers
Correct answer is option 'B'. Can you explain this answer?
In an ecosystem, herbivores represent
a)
producers
b)
primary consumers
c)
secondary consumers
d)
decomposers
|
|
Amit Sharma answered |
A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another.
(i) At the base of the food chain lie the primary producers. The primary producers are autotrophs and are most often photosynthetic organisms such as plants, algae, or cyanobacteria.
(ii) Primary consumers are the organisms that eat the primary producers. They are usually herbivores, plant-eaters, though they may be algae eaters or bacteria eaters.
(iii) Secondary consumers are the organisms that eat the primary consumers. They are generally meat-eaters called carnivores.
(iv) Tertiary consumers are the organisms that eat the secondary consumers. These are carnivore-eating carnivores, like eagles or big fish.
The process of eating and being eaten is called-- a)Food chain
- b)Food store
- c)Food web
- d)Food cycle
Correct answer is option 'C'. Can you explain this answer?
The process of eating and being eaten is called-
a)
Food chain
b)
Food store
c)
Food web
d)
Food cycle
|
|
Amit Kumar answered |
The food chain is a sequence of populations or organisms through which food and energy are passed on an ecosystem with the members of each trophic levels. A food chain shows who is eating whom. Here, organisms of higher trophic level derive its nutrients from organisms of a lower trophic level.
Which one of the following will undergo fastest bio-degradation?- a)Mango seed
- b)Wood
- c)Mango peel
- d)Mango pulp
Correct answer is option 'D'. Can you explain this answer?
Which one of the following will undergo fastest bio-degradation?
a)
Mango seed
b)
Wood
c)
Mango peel
d)
Mango pulp
|
Gaurav Kumar answered |
Mango pulp contains enzymes like polyphenol oxidase which results in its browning and later degrades it and it is mainly absent in other substances.
Which of the following constitute a food-chain ?- a)Grass, wheat and mango
- b)Grass, goat and human
- c)Goat, cow and elephant
- d)Grass, fish and goat
Correct answer is option 'B'. Can you explain this answer?
Which of the following constitute a food-chain ?
a)
Grass, wheat and mango
b)
Grass, goat and human
c)
Goat, cow and elephant
d)
Grass, fish and goat
|
Vivek Rana answered |
Grass, goat and human constitute a food chain. Grass is an autotroph i.e. it produces its own food. Grass is eaten by goat which is a herbivore. Human beings are omnivores (they eat both meat and plant foods) so they eat meat of goat. Hence this is a food chain.
“Nitrous oxide is a green house gas” the above statement is-- a)True
- b)Partially false
- c)Partially true
- d)False
Correct answer is option 'A'. Can you explain this answer?
“Nitrous oxide is a green house gas” the above statement is-
a)
True
b)
Partially false
c)
Partially true
d)
False
|
|
Amit Sharma answered |
Like other greenhouse gases, nitrous oxide absorbs radiation and traps heat in the atmosphere, where it can live for an average of 114 years, according to the EPA.
A food chain consist of- a)Producers
- b)Consumers
- c)Decomposers
- d)Producers and consumers
Correct answer is option 'D'. Can you explain this answer?
A food chain consist of
a)
Producers
b)
Consumers
c)
Decomposers
d)
Producers and consumers
|
Simran Chakraborty answered |
Food chain
A food chain is a linear sequence of organisms in an ecosystem, where each organism is the source of food for the next organism in the chain. It represents the flow of energy and nutrients from one organism to another. A basic food chain consists of three main components: producers, consumers, and decomposers. However, in this case, the correct answer is option 'D', which means the food chain consists of both producers and consumers.
Producers
Producers, also known as autotrophs, are organisms that can produce their own food through photosynthesis or chemosynthesis. They are usually plants or algae that convert sunlight, water, and carbon dioxide into glucose, which serves as their source of energy. Producers are the foundation of the food chain as they provide the energy and nutrients for all other organisms.
Consumers
Consumers, also known as heterotrophs, are organisms that obtain their energy by consuming other organisms. They cannot produce their own food and rely on consuming other organisms, including plants and other animals, to obtain energy and nutrients. Consumers are further classified into different types based on their feeding habits:
- Herbivores: These are primary consumers that feed only on plants.
- Carnivores: These are secondary or tertiary consumers that feed on other animals.
- Omnivores: These consumers have a mixed diet and feed on both plants and animals.
- Scavengers: These consumers feed on dead organisms or carrion.
- Decomposers: These consumers break down dead organic matter and release nutrients back into the ecosystem.
Decomposers
Decomposers are organisms that play a crucial role in breaking down dead organisms and organic waste materials. They include bacteria, fungi, and certain types of insects. Decomposers break down complex organic compounds into simpler forms, releasing nutrients back into the environment. These nutrients can then be used by producers to produce more food, completing the cycle.
Conclusion
In a food chain, producers are essential as they convert energy from the sun into food, which is then consumed by consumers. Consumers, in turn, provide energy and nutrients for other consumers and decomposers. Decomposers play a vital role in recycling nutrients and breaking down dead organic matter. Therefore, the correct answer to the question is option 'D', as the food chain consists of both producers and consumers.
A food chain is a linear sequence of organisms in an ecosystem, where each organism is the source of food for the next organism in the chain. It represents the flow of energy and nutrients from one organism to another. A basic food chain consists of three main components: producers, consumers, and decomposers. However, in this case, the correct answer is option 'D', which means the food chain consists of both producers and consumers.
Producers
Producers, also known as autotrophs, are organisms that can produce their own food through photosynthesis or chemosynthesis. They are usually plants or algae that convert sunlight, water, and carbon dioxide into glucose, which serves as their source of energy. Producers are the foundation of the food chain as they provide the energy and nutrients for all other organisms.
Consumers
Consumers, also known as heterotrophs, are organisms that obtain their energy by consuming other organisms. They cannot produce their own food and rely on consuming other organisms, including plants and other animals, to obtain energy and nutrients. Consumers are further classified into different types based on their feeding habits:
- Herbivores: These are primary consumers that feed only on plants.
- Carnivores: These are secondary or tertiary consumers that feed on other animals.
- Omnivores: These consumers have a mixed diet and feed on both plants and animals.
- Scavengers: These consumers feed on dead organisms or carrion.
- Decomposers: These consumers break down dead organic matter and release nutrients back into the ecosystem.
Decomposers
Decomposers are organisms that play a crucial role in breaking down dead organisms and organic waste materials. They include bacteria, fungi, and certain types of insects. Decomposers break down complex organic compounds into simpler forms, releasing nutrients back into the environment. These nutrients can then be used by producers to produce more food, completing the cycle.
Conclusion
In a food chain, producers are essential as they convert energy from the sun into food, which is then consumed by consumers. Consumers, in turn, provide energy and nutrients for other consumers and decomposers. Decomposers play a vital role in recycling nutrients and breaking down dead organic matter. Therefore, the correct answer to the question is option 'D', as the food chain consists of both producers and consumers.
Function of an ecosystem involves-- a)Energy flow and nutrient movement
- b)Energy flow only
- c)Nutrient flow only
- d)None of the above.
Correct answer is option 'A'. Can you explain this answer?
Function of an ecosystem involves-
a)
Energy flow and nutrient movement
b)
Energy flow only
c)
Nutrient flow only
d)
None of the above.
|
|
Vijay Bansal answered |
Function of an ecosystem involves:
Energy flow and nutrient movement
Explanation:
Ecosystems are complex and dynamic systems that consist of living organisms (biotic components) and their physical environment (abiotic components). The functioning of an ecosystem involves the flow of energy and the movement of nutrients.
Energy flow:
- Energy flows through an ecosystem in a unidirectional manner. It enters the ecosystem through the producers (plants) via the process of photosynthesis, where sunlight is converted into chemical energy.
- This energy is then transferred to the primary consumers (herbivores) when they consume the producers.
- The energy continues to flow through the ecosystem as it is passed on from one trophic level to another. Each trophic level represents a feeding level in the food chain.
- The energy is eventually lost as heat during various biological processes, such as respiration and movement.
Nutrient movement:
- Nutrients, on the other hand, cycle within an ecosystem. They are continuously recycled between the biotic and abiotic components.
- For example, plants absorb nutrients from the soil and incorporate them into their tissues.
- When consumers feed on these plants, they obtain the nutrients and incorporate them into their own bodies.
- When organisms die or produce waste, the nutrients are released back into the environment through processes like decomposition.
- Microorganisms decompose organic matter and break it down into simpler forms, releasing nutrients that can be used by plants again.
- This nutrient cycling ensures that essential elements, such as carbon, nitrogen, and phosphorus, are constantly available for living organisms.
Importance:
The functioning of an ecosystem is crucial for the overall health and stability of the environment. The energy flow and nutrient movement within an ecosystem are interconnected and support the following:
1. Organism survival: Energy is required for the growth, reproduction, and metabolism of organisms. Nutrients are essential for the development and functioning of their cells and tissues.
2. Food chain/web: The energy flow through different trophic levels forms the basis of food chains and food webs. This allows for the transfer of energy and nutrients between different species.
3. Ecological balance: Nutrient cycling helps maintain the balance of essential elements in the environment. This ensures that all organisms have access to the necessary nutrients for their survival.
4. Biodiversity: Energy flow and nutrient cycling support the diversity of species within an ecosystem. Different organisms have specific energy and nutrient requirements, and their interactions contribute to the overall biodiversity.
In conclusion, the function of an ecosystem involves both the flow of energy and the movement of nutrients. These processes are interconnected and play a vital role in sustaining life within the ecosystem.
Energy flow and nutrient movement
Explanation:
Ecosystems are complex and dynamic systems that consist of living organisms (biotic components) and their physical environment (abiotic components). The functioning of an ecosystem involves the flow of energy and the movement of nutrients.
Energy flow:
- Energy flows through an ecosystem in a unidirectional manner. It enters the ecosystem through the producers (plants) via the process of photosynthesis, where sunlight is converted into chemical energy.
- This energy is then transferred to the primary consumers (herbivores) when they consume the producers.
- The energy continues to flow through the ecosystem as it is passed on from one trophic level to another. Each trophic level represents a feeding level in the food chain.
- The energy is eventually lost as heat during various biological processes, such as respiration and movement.
Nutrient movement:
- Nutrients, on the other hand, cycle within an ecosystem. They are continuously recycled between the biotic and abiotic components.
- For example, plants absorb nutrients from the soil and incorporate them into their tissues.
- When consumers feed on these plants, they obtain the nutrients and incorporate them into their own bodies.
- When organisms die or produce waste, the nutrients are released back into the environment through processes like decomposition.
- Microorganisms decompose organic matter and break it down into simpler forms, releasing nutrients that can be used by plants again.
- This nutrient cycling ensures that essential elements, such as carbon, nitrogen, and phosphorus, are constantly available for living organisms.
Importance:
The functioning of an ecosystem is crucial for the overall health and stability of the environment. The energy flow and nutrient movement within an ecosystem are interconnected and support the following:
1. Organism survival: Energy is required for the growth, reproduction, and metabolism of organisms. Nutrients are essential for the development and functioning of their cells and tissues.
2. Food chain/web: The energy flow through different trophic levels forms the basis of food chains and food webs. This allows for the transfer of energy and nutrients between different species.
3. Ecological balance: Nutrient cycling helps maintain the balance of essential elements in the environment. This ensures that all organisms have access to the necessary nutrients for their survival.
4. Biodiversity: Energy flow and nutrient cycling support the diversity of species within an ecosystem. Different organisms have specific energy and nutrient requirements, and their interactions contribute to the overall biodiversity.
In conclusion, the function of an ecosystem involves both the flow of energy and the movement of nutrients. These processes are interconnected and play a vital role in sustaining life within the ecosystem.
Assertion (A): All organisms such as plants, animals, microorganisms, and human beings interact with each other and maintain a balance in nature.Reason (R): An ecosystem consists of biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil, and minerals.- a)If both Assertion and Reason are true and Reason is the correct explanation of Assertion
- b)If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
- c)If Assertion is true but Reason is false
- d)If both Assertion and Reason are false
Correct answer is option 'B'. Can you explain this answer?
Assertion (A): All organisms such as plants, animals, microorganisms, and human beings interact with each other and maintain a balance in nature.
Reason (R): An ecosystem consists of biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil, and minerals.
a)
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
b)
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c)
If Assertion is true but Reason is false
d)
If both Assertion and Reason are false
|
Jyoti Mehta answered |
Assertion and Reason Overview
The assertion (A) claims that all organisms, including plants, animals, microorganisms, and humans, interact with each other and maintain a balance in nature. The reason (R) explains that an ecosystem consists of biotic components (living organisms) and abiotic components (physical factors like temperature, rainfall, etc.).
Analysis of Assertion (A)
- The assertion is true.
- Organisms interact in various ways, such as through food webs, nutrient cycling, and competition.
- These interactions contribute to the ecological balance, ensuring that populations of different species remain stable.
Analysis of Reason (R)
- The reason is also true.
- An ecosystem is indeed composed of both biotic and abiotic factors, which together create the environment in which organisms live and interact.
- Abiotic factors influence the types of organisms that can thrive in an ecosystem and their interactions.
Connection Between Assertion and Reason
- While both statements are true, the reason does not directly explain the assertion.
- The assertion focuses on the interactions and balance among organisms, while the reason provides a broader context about what constitutes an ecosystem.
- The dynamics of interaction among organisms involve more complex relationships than just the presence of abiotic factors.
Conclusion
- Therefore, the correct option is (b): both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
- This distinction highlights that while the structure of ecosystems is essential, the interactions among organisms are crucial for maintaining ecological balance.
The assertion (A) claims that all organisms, including plants, animals, microorganisms, and humans, interact with each other and maintain a balance in nature. The reason (R) explains that an ecosystem consists of biotic components (living organisms) and abiotic components (physical factors like temperature, rainfall, etc.).
Analysis of Assertion (A)
- The assertion is true.
- Organisms interact in various ways, such as through food webs, nutrient cycling, and competition.
- These interactions contribute to the ecological balance, ensuring that populations of different species remain stable.
Analysis of Reason (R)
- The reason is also true.
- An ecosystem is indeed composed of both biotic and abiotic factors, which together create the environment in which organisms live and interact.
- Abiotic factors influence the types of organisms that can thrive in an ecosystem and their interactions.
Connection Between Assertion and Reason
- While both statements are true, the reason does not directly explain the assertion.
- The assertion focuses on the interactions and balance among organisms, while the reason provides a broader context about what constitutes an ecosystem.
- The dynamics of interaction among organisms involve more complex relationships than just the presence of abiotic factors.
Conclusion
- Therefore, the correct option is (b): both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
- This distinction highlights that while the structure of ecosystems is essential, the interactions among organisms are crucial for maintaining ecological balance.
Ozone depletion has resulted in-- a)Less uv radiations on earth
- b)More uv radiations on earth
- c)Warming of earth
- d)Decrease in temperature
Correct answer is option 'B'. Can you explain this answer?
Ozone depletion has resulted in-
a)
Less uv radiations on earth
b)
More uv radiations on earth
c)
Warming of earth
d)
Decrease in temperature
|
|
Vicky Singh answered |
B
more uv radiation increase more heat which further increase temperatures
more uv radiation increase more heat which further increase temperatures
An example of man-made ecosystem is -- a)Desert
- b)Garden
- c)River
- d)Grassland
Correct answer is option 'B'. Can you explain this answer?
An example of man-made ecosystem is -
a)
Desert
b)
Garden
c)
River
d)
Grassland
|
Harshit Roy answered |
Answer is garden because of course all others are natural i.e. created by nature but garden is built by human beings that's why it's a man made ecosystem
Which of the following is non-biodegradable ?- a)Tea leaves
- b)Nylon
- c)remains of animals
- d)fleece of sheep
Correct answer is option 'B'. Can you explain this answer?
Which of the following is non-biodegradable ?
a)
Tea leaves
b)
Nylon
c)
remains of animals
d)
fleece of sheep
|
Vijayalaxmi Padaganur answered |
Because Nylon is the polymer which is non degradable
Which of the following is an example of biodegradable waste?- a)Plastic bags
- b)Glass bottles
- c)Fruit peels
- d)Metal cans
Correct answer is option 'C'. Can you explain this answer?
a)
Plastic bags
b)
Glass bottles
c)
Fruit peels
d)
Metal cans
|
Edu Impact answered |
Fruit peels are organic and can decompose naturally, making them biodegradable waste.
In due given food chain, suppose the amount of energy available at third trophic level is 50 KJ, what will be the energy available at due producer level ?- a)5000 KJ
- b)5 KJ
- c)500 KJ
- d)50 KJ
Correct answer is option 'A'. Can you explain this answer?
In due given food chain, suppose the amount of energy available at third trophic level is 50 KJ, what will be the energy available at due producer level ?
a)
5000 KJ
b)
5 KJ
c)
500 KJ
d)
50 KJ
|
Rekha iyer answered |
Only 10% of the energy present is given to the consumer at the next level, of the total energy the level/animal has.
Therefore, if 4th Level = 5kJ
3rd Level = 50kJ
2nd Level = 500kJ
Producer = 5,000kJ
Therefore, if 4th Level = 5kJ
3rd Level = 50kJ
2nd Level = 500kJ
Producer = 5,000kJ
The decomposers in an ecosystem-- a)Convert organic material to inorganic forms.
- b)Do not breakdown organic compounds.
- c)Convert inorganic materials into organic compounds.
- d)Convert inorganic material to simples forms.
Correct answer is option 'A'. Can you explain this answer?
The decomposers in an ecosystem-
a)
Convert organic material to inorganic forms.
b)
Do not breakdown organic compounds.
c)
Convert inorganic materials into organic compounds.
d)
Convert inorganic material to simples forms.
|
Ritika Bajaj answered |
Understanding Decomposers in Ecosystems
Decomposers play a crucial role in the functioning of ecosystems. Their primary task is to break down organic matter, which is essential for nutrient cycling.
Role of Decomposers
- Decomposers, such as bacteria, fungi, and certain insects, convert dead plants and animals into simpler inorganic materials.
- They facilitate the decay process, breaking down complex organic compounds into simpler substances like carbon dioxide, water, and minerals.
Nutrient Cycling
- By converting organic material to inorganic forms, decomposers release nutrients back into the soil.
- This process enriches the soil, making it available for plants to absorb, thus supporting new growth and maintaining the ecosystem's health.
Importance in Ecosystem Balance
- Decomposers help maintain ecological balance by recycling nutrients and ensuring that energy flows through the food web.
- Without decomposers, ecosystems would be overwhelmed with organic waste, leading to a decline in soil fertility and overall biodiversity.
Conclusion
In conclusion, the correct answer is option 'A' because decomposers are essential for converting organic material into inorganic forms, thereby supporting the continuous cycle of life within ecosystems. Their actions are vital for sustaining healthy environments and promoting biodiversity.
Decomposers play a crucial role in the functioning of ecosystems. Their primary task is to break down organic matter, which is essential for nutrient cycling.
Role of Decomposers
- Decomposers, such as bacteria, fungi, and certain insects, convert dead plants and animals into simpler inorganic materials.
- They facilitate the decay process, breaking down complex organic compounds into simpler substances like carbon dioxide, water, and minerals.
Nutrient Cycling
- By converting organic material to inorganic forms, decomposers release nutrients back into the soil.
- This process enriches the soil, making it available for plants to absorb, thus supporting new growth and maintaining the ecosystem's health.
Importance in Ecosystem Balance
- Decomposers help maintain ecological balance by recycling nutrients and ensuring that energy flows through the food web.
- Without decomposers, ecosystems would be overwhelmed with organic waste, leading to a decline in soil fertility and overall biodiversity.
Conclusion
In conclusion, the correct answer is option 'A' because decomposers are essential for converting organic material into inorganic forms, thereby supporting the continuous cycle of life within ecosystems. Their actions are vital for sustaining healthy environments and promoting biodiversity.
What is one way to properly store food to prevent waste?- a)Leave food out in the open
- b)Store food at high temperatures
- c)Keep food in a refrigerator
- d)Cover food with plastic bags
Correct answer is option 'C'. Can you explain this answer?
a)
Leave food out in the open
b)
Store food at high temperatures
c)
Keep food in a refrigerator
d)
Cover food with plastic bags
|
Subset Academy answered |
Refrigerating food slows down the growth of microorganisms, preventing spoilage and reducing waste.
What does "reduce" in waste management mean?- a)To burn waste
- b)To minimize the amount of waste produced
- c)To throw waste into the ocean
- d)To bury waste in the ground
Correct answer is option 'B'. Can you explain this answer?
a)
To burn waste
b)
To minimize the amount of waste produced
c)
To throw waste into the ocean
d)
To bury waste in the ground
|
Manisha Joshi answered |
Understanding "Reduce" in Waste Management
Waste management is crucial for maintaining a clean and healthy environment. One of the key principles in waste management is the concept of "reduce."
What Does "Reduce" Mean?
- Definition: To "reduce" means to minimize the amount of waste produced in the first place. This involves making conscious choices to limit consumption and prevent waste generation.
Importance of Reducing Waste
- Environmental Impact: Reducing waste helps conserve natural resources and reduces pollution. By producing less waste, we lessen the burden on landfills and decrease greenhouse gas emissions.
- Sustainability: Reducing waste supports sustainability. It encourages the use of materials efficiently and promotes a circular economy where resources are reused and recycled rather than discarded.
Actions to Reduce Waste
- Choose Wisely: Opt for products with less packaging. For example, buy items in bulk or choose brands that use eco-friendly packaging.
- Practice Minimalism: Embrace a minimalist lifestyle by only purchasing what you truly need. This helps in reducing unnecessary consumption.
- Repurpose and Donate: Instead of throwing away items that are no longer needed, consider repurposing them or donating to those in need.
Conclusion
By focusing on reducing waste, we can significantly contribute to a healthier planet. The goal is to produce less waste, thereby making our communities cleaner and more sustainable for future generations. Remember, every small action counts!
Waste management is crucial for maintaining a clean and healthy environment. One of the key principles in waste management is the concept of "reduce."
What Does "Reduce" Mean?
- Definition: To "reduce" means to minimize the amount of waste produced in the first place. This involves making conscious choices to limit consumption and prevent waste generation.
Importance of Reducing Waste
- Environmental Impact: Reducing waste helps conserve natural resources and reduces pollution. By producing less waste, we lessen the burden on landfills and decrease greenhouse gas emissions.
- Sustainability: Reducing waste supports sustainability. It encourages the use of materials efficiently and promotes a circular economy where resources are reused and recycled rather than discarded.
Actions to Reduce Waste
- Choose Wisely: Opt for products with less packaging. For example, buy items in bulk or choose brands that use eco-friendly packaging.
- Practice Minimalism: Embrace a minimalist lifestyle by only purchasing what you truly need. This helps in reducing unnecessary consumption.
- Repurpose and Donate: Instead of throwing away items that are no longer needed, consider repurposing them or donating to those in need.
Conclusion
By focusing on reducing waste, we can significantly contribute to a healthier planet. The goal is to produce less waste, thereby making our communities cleaner and more sustainable for future generations. Remember, every small action counts!
In the following groups of materials, which group contains only non biodegradable items.- a)Polythene, detergent, PVC
- b)Plastic, Bakelite, Leaf
- c)Plastic, detergent, grass
- d)Wood, paper leather
Correct answer is option 'A'. Can you explain this answer?
In the following groups of materials, which group contains only non biodegradable items.
a)
Polythene, detergent, PVC
b)
Plastic, Bakelite, Leaf
c)
Plastic, detergent, grass
d)
Wood, paper leather
|
Dr Manju Sen answered |
To determine which group contains only non-biodegradable items, we need to analyze each group of materials and identify the non-biodegradable items present in each group.
Group A:
- Polythene: Non-biodegradable
- Detergent: Non-biodegradable
- PVC: Non-biodegradable
Group B:
- Plastic: Non-biodegradable
- Bakelite: Non-biodegradable
- Leaf: Biodegradable
Group C:
- Plastic: Non-biodegradable
- Detergent: Non-biodegradable
- Grass: Biodegradable
Group D:
- Wood: Biodegradable
- Paper: Biodegradable
- Leather: Biodegradable
From the analysis, we can see that only Group A (Polythene, detergent, PVC) contains only non-biodegradable items. The other groups have at least one biodegradable item present.
Therefore, the correct answer is Group A.
Assertion (A): Biodegradable substances have a positive impact on the environment.Reason (R): Biodegradable substances break down naturally into harmless compounds.- a)If both Assertion and Reason are true and Reason is the correct explanation of Assertion
- b)If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
- c)If Assertion is true but Reason is false
- d)If both Assertion and Reason are false
Correct answer is option 'A'. Can you explain this answer?
Assertion (A): Biodegradable substances have a positive impact on the environment.
Reason (R): Biodegradable substances break down naturally into harmless compounds.
a)
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
b)
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c)
If Assertion is true but Reason is false
d)
If both Assertion and Reason are false
|
Mira Joshi answered |
Understanding the Assertion and Reason
The Assertion (A) states that biodegradable substances have a positive impact on the environment. The Reason (R) explains that these substances break down naturally into harmless compounds.
Analysis of Assertion (A)
- Biodegradable substances, such as food waste and paper, undergo natural decomposition.
- This process reduces pollution and minimizes landfill waste, contributing positively to environmental health.
Analysis of Reason (R)
- The breakdown of biodegradable materials into harmless compounds is a fundamental characteristic.
- This natural decomposition process prevents the accumulation of harmful substances in the environment, thus supporting sustainability.
Connection Between Assertion and Reason
- The reason provided (R) directly supports the assertion (A).
- If biodegradable substances break down into harmless compounds, they indeed have a positive impact on the environment by reducing waste and pollution.
Conclusion
- Since both the Assertion and Reason are true, and the Reason effectively explains why the Assertion is true, the correct answer is option 'A'.
- This relationship highlights the significance of choosing biodegradable materials in fostering a healthier ecosystem.
In summary, biodegradable substances play a crucial role in environmental preservation by breaking down naturally and minimizing harmful waste.
The Assertion (A) states that biodegradable substances have a positive impact on the environment. The Reason (R) explains that these substances break down naturally into harmless compounds.
Analysis of Assertion (A)
- Biodegradable substances, such as food waste and paper, undergo natural decomposition.
- This process reduces pollution and minimizes landfill waste, contributing positively to environmental health.
Analysis of Reason (R)
- The breakdown of biodegradable materials into harmless compounds is a fundamental characteristic.
- This natural decomposition process prevents the accumulation of harmful substances in the environment, thus supporting sustainability.
Connection Between Assertion and Reason
- The reason provided (R) directly supports the assertion (A).
- If biodegradable substances break down into harmless compounds, they indeed have a positive impact on the environment by reducing waste and pollution.
Conclusion
- Since both the Assertion and Reason are true, and the Reason effectively explains why the Assertion is true, the correct answer is option 'A'.
- This relationship highlights the significance of choosing biodegradable materials in fostering a healthier ecosystem.
In summary, biodegradable substances play a crucial role in environmental preservation by breaking down naturally and minimizing harmful waste.
How do we properly manage non-biodegradable waste?- a)Burn it
- b)Compost it
- c)Recycle it
- d)Bury it
Correct answer is option 'C'. Can you explain this answer?
a)
Burn it
b)
Compost it
c)
Recycle it
d)
Bury it
|
|
Shivani Banerjee answered |
Understanding Non-Biodegradable Waste
Non-biodegradable waste refers to materials that do not decompose naturally in the environment. This includes plastics, glass, metals, and certain chemicals. Given the environmental impact of this waste, proper management is crucial.
Why Recycling is Key
Recycling is the most effective method for managing non-biodegradable waste. Here’s why:
- Reduces Landfill Waste
Recycling decreases the amount of waste sent to landfills, which can overflow and lead to pollution.
- Conserves Resources
It helps to conserve natural resources by reusing materials instead of extracting new ones. For instance, recycling aluminum saves 95% of the energy needed to create new aluminum from raw materials.
- Minimizes Pollution
Recycling reduces air and water pollution associated with the production of new materials, making it a cleaner alternative.
- Encourages Sustainable Practices
By recycling, we promote a circular economy where materials are reused, minimizing the need for new resources and reducing the environmental footprint.
Other Options Explained
- Burning
While burning waste can reduce volume, it often releases harmful toxins into the atmosphere.
- Composting
Composting is only suitable for biodegradable waste like food scraps and yard waste, not for non-biodegradable materials.
- Burying
Burying non-biodegradable waste in landfills can lead to soil and water contamination over time.
Conclusion
In summary, recycling is the correct approach for managing non-biodegradable waste. It not only conserves resources and reduces pollution but also fosters sustainable practices for a healthier planet.
Non-biodegradable waste refers to materials that do not decompose naturally in the environment. This includes plastics, glass, metals, and certain chemicals. Given the environmental impact of this waste, proper management is crucial.
Why Recycling is Key
Recycling is the most effective method for managing non-biodegradable waste. Here’s why:
- Reduces Landfill Waste
Recycling decreases the amount of waste sent to landfills, which can overflow and lead to pollution.
- Conserves Resources
It helps to conserve natural resources by reusing materials instead of extracting new ones. For instance, recycling aluminum saves 95% of the energy needed to create new aluminum from raw materials.
- Minimizes Pollution
Recycling reduces air and water pollution associated with the production of new materials, making it a cleaner alternative.
- Encourages Sustainable Practices
By recycling, we promote a circular economy where materials are reused, minimizing the need for new resources and reducing the environmental footprint.
Other Options Explained
- Burning
While burning waste can reduce volume, it often releases harmful toxins into the atmosphere.
- Composting
Composting is only suitable for biodegradable waste like food scraps and yard waste, not for non-biodegradable materials.
- Burying
Burying non-biodegradable waste in landfills can lead to soil and water contamination over time.
Conclusion
In summary, recycling is the correct approach for managing non-biodegradable waste. It not only conserves resources and reduces pollution but also fosters sustainable practices for a healthier planet.
“Flow of energy is unidirectional”. It means that-- a)Energy always flows form east to west direction.
- b)The energy of the autotrophs reaches back to the solar input.
- c)Energy which passes to the higher trophic levels doesn’t come back to lower trophic levels.
- d)None of these.
Correct answer is option 'C'. Can you explain this answer?
“Flow of energy is unidirectional”. It means that-
a)
Energy always flows form east to west direction.
b)
The energy of the autotrophs reaches back to the solar input.
c)
Energy which passes to the higher trophic levels doesn’t come back to lower trophic levels.
d)
None of these.
|
|
Rajesh Khatri answered |
The correct answer is c) Energy which passes to the higher trophic levels doesn’t come back to lower trophic levels.
The flow of energy in an ecosystem is unidirectional, which means that it flows in one direction only. In the context of a food chain or food web, this means that energy flows from lower trophic levels, or producers (such as plants), to higher trophic levels, or consumers (such as herbivores and carnivores). Once the energy is passed to a higher trophic level, it does not flow back to a lower trophic level. For example, once a herbivore consumes a plant, the energy contained in the plant is transferred to the herbivore, but it is not returned to the plant. Instead, the energy is passed along to higher trophic levels if the herbivore is eaten by a carnivore, or it is lost as heat through metabolism or other processes.
Assertion (A): Energy available at each trophic level gets diminished progressively due to the loss of energy at each level.Reason (R): Food chains generally consist of only three or four steps due to the significant energy loss at each trophic level.- a)If both Assertion and Reason are true and Reason is the correct explanation of Assertion
- b)If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
- c)If Assertion is true but Reason is false
- d)If both Assertion and Reason are false
Correct answer is option 'B'. Can you explain this answer?
Assertion (A): Energy available at each trophic level gets diminished progressively due to the loss of energy at each level.
Reason (R): Food chains generally consist of only three or four steps due to the significant energy loss at each trophic level.
a)
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
b)
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c)
If Assertion is true but Reason is false
d)
If both Assertion and Reason are false
|
Future Foundation Institute answered |
- The Assertion is true.It is a fundamental concept in ecology that energy diminishes at each trophic level in a food chain. This is due to the loss of energy during metabolism, heat loss, and other inefficiencies in energy transfer.
- The Reason is also true.Food chains are limited in length due to the significant energy loss that occurs at each trophic level. This limitation is a result of the inefficiency of energy transfer between trophic levels.
- However, the Reason is not the correct explanation of the Assertion.While both statements are true, the fact that energy diminishes at each trophic level does not directly explain why food chains generally consist of only three or four steps. The length of food chains is influenced by various factors beyond just energy loss.
Find the incorrect statement-- a)Soil provides water and minerals for the plant.
- b)Soil provides disease resistant environment for plants.
- c)Soil provides the substratum for plant growth.
- d)Soil provides necessary nutrients for plants.
Correct answer is option 'B'. Can you explain this answer?
Find the incorrect statement-
a)
Soil provides water and minerals for the plant.
b)
Soil provides disease resistant environment for plants.
c)
Soil provides the substratum for plant growth.
d)
Soil provides necessary nutrients for plants.
|
Maqsood Alam answered |
A, c, d
Which of the following constitutes the forth trophic level ?- a)Top carnivores
- b)Herbivores
- c)Small carnivores
- d)Plants
Correct answer is option 'A'. Can you explain this answer?
Which of the following constitutes the forth trophic level ?
a)
Top carnivores
b)
Herbivores
c)
Small carnivores
d)
Plants
|
|
Saquib raza khan answered |
Level 1: Plants and algae make their own food and are called producers. Level 2: Herbivores eat plants and are called primary consumers. Level 3: Carnivores that eat herbivores are called secondary consumers. Level 4: Carnivores that eat other carnivores are called tertiary consumers.
Choose the correctly matched pair:- a)10% Rule - Energy transferred to the next trophic level
- b)Biological Magnification - Decrease in chemical concentration at higher trophic levels
- c)Food Web - Linear sequence of organisms
- d)Unidirectional Energy Flow - Energy flows back to autotrophs
Correct answer is option 'A'. Can you explain this answer?
a)
10% Rule - Energy transferred to the next trophic level
b)
Biological Magnification - Decrease in chemical concentration at higher trophic levels
c)
Food Web - Linear sequence of organisms
d)
Unidirectional Energy Flow - Energy flows back to autotrophs
|
BT Educators answered |
- Option A: 10% Rule - Energy transferred to the next trophic level: Explanation: The 10% Rule indicates that only about 10% of the energy from one trophic level is transferred to the next level. The rest is lost as heat, used in metabolism, or remains unassimilated.
- Option B: Biological Magnification - Decrease in chemical concentration at higher trophic levels - Incorrect: Biological Magnification refers to the increase in concentration of harmful chemicals at higher trophic levels, not a decrease.
- Option C: Food Web - Linear sequence of organisms - Incorrect: A food web represents a complex network of feeding relationships, not a linear sequence. A linear sequence is referred to as a food chain.
- Option D: Unidirectional Energy Flow - Energy flows back to autotrophs - Incorrect: Unidirectional Energy Flow means that energy flows in one direction—from the sun to autotrophs (producers) to various levels of consumers and does not flow back.
An ecosystem consists of biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil, and _______.- a)Minerals
- b)Gravity
- c)Light
- d)Electricity
Correct answer is option 'C'. Can you explain this answer?
An ecosystem consists of biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil, and _______.
a)
Minerals
b)
Gravity
c)
Light
d)
Electricity
|
Kamna Science Academy answered |
Light is an important abiotic component of an ecosystem. It influences processes like photosynthesis in plants, which is essential for life in the ecosystem. Other options such as -
a) Minerals: Minerals are part of the soil and contribute to the nutrient cycle in ecosystems. However, they are generally considered part of the soil (which is an abiotic component) rather than an independent abiotic factor. Minerals help sustain plant life, but they aren't usually listed as a separate abiotic component like light.
b) Gravity: While gravity does affect the movement of water and gases in ecosystems, it is not typically considered a primary abiotic factor in an ecosystem. It is a fundamental physical force but does not directly impact the living processes like temperature, rainfall, or light.
d) Electricity: Electricity itself is not typically a direct abiotic factor in most ecosystems. While it can affect certain human-made systems or natural phenomena (like lightning), it is not as fundamental to the operation of ecosystems as light, temperature, or rainfall.
Therefore, Correct Answer- Option C
What is one way to reduce plastic waste?- a)Using plastic bags for shopping
- b)Reusing glass bottles
- c)Buying metal cans
- d)Burning plastic
Correct answer is option 'B'. Can you explain this answer?
What is one way to reduce plastic waste?
a)
Using plastic bags for shopping
b)
Reusing glass bottles
c)
Buying metal cans
d)
Burning plastic
|
Stoneridge Institute answered |
- One effective way to reduce plastic waste is by reusing glass bottles.
- This method helps to minimise the use of plastic containers, which are a major source of pollution.
- Using glass, which is easily recyclable, contributes to a more sustainable environment.
Which process involves using waste materials to create new products?- a)Burning
- b)Composting
- c)Recycling
- d)Storing
Correct answer is option 'C'. Can you explain this answer?
a)
Burning
b)
Composting
c)
Recycling
d)
Storing
|
Muskaan Reddy answered |
Understanding Recycling
Recycling is the process that transforms waste materials into new products, significantly benefiting the environment and conserving resources. Here’s a closer look at what recycling entails:
What is Recycling?
- Recycling involves collecting, processing, and converting materials that would otherwise be discarded.
- Common recyclable materials include paper, cardboard, glass, metals, and some plastics.
How Does Recycling Work?
- Collection: Recyclable materials are gathered from homes, businesses, and public spaces.
- Processing: The collected materials are sorted and cleaned to prepare them for manufacturing.
- Manufacturing: Recyclables are then transformed into new products. For example, recycled paper can be made into new paper products, and glass can be melted down to create new glass items.
Benefits of Recycling
- Conserves Natural Resources: Recycling reduces the need for raw materials, preserving forests, water, and minerals.
- Reduces Waste: It minimizes the amount of waste sent to landfills, which can help reduce pollution.
- Saves Energy: Producing new products from recycled materials often uses less energy compared to creating them from virgin materials.
- Promotes Sustainability: Recycling supports a sustainable economy by encouraging the responsible use of resources.
Conclusion
Recycling is a crucial process in managing waste and promoting environmental health. It allows us to turn waste into valuable resources, making it an essential practice for a sustainable future. By participating in recycling, individuals can contribute to conserving our planet's resources and reducing our environmental footprint.
Recycling is the process that transforms waste materials into new products, significantly benefiting the environment and conserving resources. Here’s a closer look at what recycling entails:
What is Recycling?
- Recycling involves collecting, processing, and converting materials that would otherwise be discarded.
- Common recyclable materials include paper, cardboard, glass, metals, and some plastics.
How Does Recycling Work?
- Collection: Recyclable materials are gathered from homes, businesses, and public spaces.
- Processing: The collected materials are sorted and cleaned to prepare them for manufacturing.
- Manufacturing: Recyclables are then transformed into new products. For example, recycled paper can be made into new paper products, and glass can be melted down to create new glass items.
Benefits of Recycling
- Conserves Natural Resources: Recycling reduces the need for raw materials, preserving forests, water, and minerals.
- Reduces Waste: It minimizes the amount of waste sent to landfills, which can help reduce pollution.
- Saves Energy: Producing new products from recycled materials often uses less energy compared to creating them from virgin materials.
- Promotes Sustainability: Recycling supports a sustainable economy by encouraging the responsible use of resources.
Conclusion
Recycling is a crucial process in managing waste and promoting environmental health. It allows us to turn waste into valuable resources, making it an essential practice for a sustainable future. By participating in recycling, individuals can contribute to conserving our planet's resources and reducing our environmental footprint.
The energy available at each trophic level gets diminished progressively due to loss of energy at each ____.- a)producers
- b)autotrophs
- c)trophic level
- d)consumers
Correct answer is option 'C'. Can you explain this answer?
The energy available at each trophic level gets diminished progressively due to loss of energy at each ____.
a)
producers
b)
autotrophs
c)
trophic level
d)
consumers
|
|
Anagha Shah answered |
The Concept of Trophic Levels
In an ecosystem, energy flows through various trophic levels, which are hierarchical stages represented by producers, consumers, and decomposers. Each level plays a crucial role in the energy transfer process.
Energy Loss at Each Trophic Level
Energy diminishes significantly at each trophic level due to several factors:
- Energy Conversion Efficiency: Only about 10% of the energy from one trophic level is passed on to the next. The rest is lost primarily as heat through metabolic processes.
- Metabolic Processes: Organisms at each level use energy for growth, reproduction, and maintenance, resulting in energy loss during cellular respiration and other metabolic activities.
- Incomplete Consumption: Not all biomass of one trophic level is consumed by the next. For instance, a herbivore may not eat all parts of a plant, leading to further energy loss.
Hierarchy of Trophic Levels
In a typical food chain:
- Producers: These are autotrophs (like plants) that convert solar energy into chemical energy through photosynthesis. They form the base of the food chain.
- Primary Consumers: Herbivores that feed on producers, obtaining energy but losing a significant portion in the process.
- Secondary and Tertiary Consumers: Carnivores that consume herbivores and other carnivores. With each step up the chain, energy diminishes further.
Conclusion
The correct answer is option 'C' because the energy available at each trophic level diminishes progressively due to losses incurred at each trophic level. Understanding this concept is vital for ecological studies and conservation efforts.
In an ecosystem, energy flows through various trophic levels, which are hierarchical stages represented by producers, consumers, and decomposers. Each level plays a crucial role in the energy transfer process.
Energy Loss at Each Trophic Level
Energy diminishes significantly at each trophic level due to several factors:
- Energy Conversion Efficiency: Only about 10% of the energy from one trophic level is passed on to the next. The rest is lost primarily as heat through metabolic processes.
- Metabolic Processes: Organisms at each level use energy for growth, reproduction, and maintenance, resulting in energy loss during cellular respiration and other metabolic activities.
- Incomplete Consumption: Not all biomass of one trophic level is consumed by the next. For instance, a herbivore may not eat all parts of a plant, leading to further energy loss.
Hierarchy of Trophic Levels
In a typical food chain:
- Producers: These are autotrophs (like plants) that convert solar energy into chemical energy through photosynthesis. They form the base of the food chain.
- Primary Consumers: Herbivores that feed on producers, obtaining energy but losing a significant portion in the process.
- Secondary and Tertiary Consumers: Carnivores that consume herbivores and other carnivores. With each step up the chain, energy diminishes further.
Conclusion
The correct answer is option 'C' because the energy available at each trophic level diminishes progressively due to losses incurred at each trophic level. Understanding this concept is vital for ecological studies and conservation efforts.
Autotrophs or producers are at the _______ trophic level in a food chain.- a)Primary
- b)Secondary
- c)Tertiary
- d)Quaternary
Correct answer is option 'A'. Can you explain this answer?
Autotrophs or producers are at the _______ trophic level in a food chain.
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
|
|
Pranjal Patel answered |
Understanding Trophic Levels
In an ecosystem, organisms are categorized into different trophic levels based on their role in the food chain. This classification helps in understanding the flow of energy and nutrients within an ecosystem.
What Are Autotrophs?
- Autotrophs, also known as producers, are organisms that can produce their own food through photosynthesis or chemosynthesis.
- Examples include plants, algae, and certain bacteria.
Position of Autotrophs in the Trophic Levels
- Autotrophs occupy the first trophic level in a food chain.
- This is because they are the primary source of energy for all other organisms.
Why are They Called Primary Producers?
- The term "primary producer" signifies their role in converting inorganic substances (like sunlight, water, and carbon dioxide) into organic matter (food).
- They form the base of the food chain and support all other trophic levels.
Flow of Energy in Ecosystems
- Energy flows from autotrophs to herbivores (primary consumers) and then to carnivores (secondary and tertiary consumers).
- Each subsequent trophic level relies on the energy produced by the level below it.
Conclusion
- Therefore, the correct answer to the question is option 'A': Autotrophs or producers are at the primary trophic level in a food chain.
- Understanding this fundamental concept is crucial for studying ecology and environmental science.
In an ecosystem, organisms are categorized into different trophic levels based on their role in the food chain. This classification helps in understanding the flow of energy and nutrients within an ecosystem.
What Are Autotrophs?
- Autotrophs, also known as producers, are organisms that can produce their own food through photosynthesis or chemosynthesis.
- Examples include plants, algae, and certain bacteria.
Position of Autotrophs in the Trophic Levels
- Autotrophs occupy the first trophic level in a food chain.
- This is because they are the primary source of energy for all other organisms.
Why are They Called Primary Producers?
- The term "primary producer" signifies their role in converting inorganic substances (like sunlight, water, and carbon dioxide) into organic matter (food).
- They form the base of the food chain and support all other trophic levels.
Flow of Energy in Ecosystems
- Energy flows from autotrophs to herbivores (primary consumers) and then to carnivores (secondary and tertiary consumers).
- Each subsequent trophic level relies on the energy produced by the level below it.
Conclusion
- Therefore, the correct answer to the question is option 'A': Autotrophs or producers are at the primary trophic level in a food chain.
- Understanding this fundamental concept is crucial for studying ecology and environmental science.
The formula of Ozone is _______- a)O3
- b)O2
- c)O4
- d)O6
Correct answer is option 'A'. Can you explain this answer?
The formula of Ozone is _______
a)
O3
b)
O2
c)
O4
d)
O6
|
|
Tanvi patil answered |
The formula of Ozone is O3.
Explanation:
What is Ozone?
Ozone is a gas that is made up of three oxygen atoms bonded together. It is a pale blue gas with a pungent odor. Ozone is present in small amounts in the Earth's atmosphere and plays an important role in the ozone layer.
The Composition of Ozone
The composition of ozone is determined by the number of atoms present in its molecule. In the case of ozone, there are three oxygen atoms bonded together.
Chemical Formula of Ozone
The chemical formula of a substance represents the types and numbers of atoms in its molecule. In the case of ozone, the chemical formula is O3. The 'O' represents oxygen, and the subscript '3' indicates that there are three oxygen atoms in each ozone molecule.
Formation of Ozone
Ozone is formed in the Earth's atmosphere through a process called photodissociation. When ultraviolet (UV) radiation from the Sun interacts with oxygen molecules (O2), it causes them to split apart. The resulting oxygen atoms (O) can then react with other oxygen molecules to form ozone (O3).
Properties of Ozone
Ozone is a highly reactive gas. It is an excellent oxidizing agent and can react with a wide range of substances. Ozone is also unstable, meaning it can easily decompose back into oxygen molecules. Its reactivity and instability make ozone useful for various applications, such as water purification and air disinfection.
The Importance of Ozone
The ozone layer, located in the Earth's stratosphere, plays a crucial role in protecting life on Earth. It absorbs the majority of the Sun's harmful ultraviolet (UV) radiation, preventing it from reaching the Earth's surface. This helps to protect living organisms from the harmful effects of UV radiation, such as skin cancer and damage to the environment.
In conclusion, the formula of ozone is O3, indicating that it consists of three oxygen atoms bonded together.
Explanation:
What is Ozone?
Ozone is a gas that is made up of three oxygen atoms bonded together. It is a pale blue gas with a pungent odor. Ozone is present in small amounts in the Earth's atmosphere and plays an important role in the ozone layer.
The Composition of Ozone
The composition of ozone is determined by the number of atoms present in its molecule. In the case of ozone, there are three oxygen atoms bonded together.
Chemical Formula of Ozone
The chemical formula of a substance represents the types and numbers of atoms in its molecule. In the case of ozone, the chemical formula is O3. The 'O' represents oxygen, and the subscript '3' indicates that there are three oxygen atoms in each ozone molecule.
Formation of Ozone
Ozone is formed in the Earth's atmosphere through a process called photodissociation. When ultraviolet (UV) radiation from the Sun interacts with oxygen molecules (O2), it causes them to split apart. The resulting oxygen atoms (O) can then react with other oxygen molecules to form ozone (O3).
Properties of Ozone
Ozone is a highly reactive gas. It is an excellent oxidizing agent and can react with a wide range of substances. Ozone is also unstable, meaning it can easily decompose back into oxygen molecules. Its reactivity and instability make ozone useful for various applications, such as water purification and air disinfection.
The Importance of Ozone
The ozone layer, located in the Earth's stratosphere, plays a crucial role in protecting life on Earth. It absorbs the majority of the Sun's harmful ultraviolet (UV) radiation, preventing it from reaching the Earth's surface. This helps to protect living organisms from the harmful effects of UV radiation, such as skin cancer and damage to the environment.
In conclusion, the formula of ozone is O3, indicating that it consists of three oxygen atoms bonded together.
Which trophic level in a food chain consists of autotrophs or producers?- a)First trophic level
- b)Second trophic level
- c)Third trophic level
- d)Fourth trophic level
Correct answer is option 'A'. Can you explain this answer?
Which trophic level in a food chain consists of autotrophs or producers?
a)
First trophic level
b)
Second trophic level
c)
Third trophic level
d)
Fourth trophic level
|
|
Pranjal Patel answered |
Trophic Levels in a Food Chain
In an ecosystem, the food chain is organized into different trophic levels, which represent the flow of energy and nutrients. Each level consists of different types of organisms, categorized primarily based on their method of obtaining energy.
First Trophic Level: Autotrophs or Producers
The first trophic level is occupied by autotrophs, commonly known as producers. These organisms play a crucial role in the ecosystem. Here’s why:
- Definition of Autotrophs: Autotrophs are organisms that can produce their own food using sunlight (photosynthesis) or chemical energy (chemosynthesis).
- Examples: Common examples include plants, algae, and some bacteria. They convert solar energy into chemical energy, forming the base of the food web.
- Significance: By synthesizing organic compounds, they provide energy for all other trophic levels (herbivores, carnivores, etc.), establishing the foundation for the entire ecosystem.
Subsequent Trophic Levels
While the first trophic level consists of producers, the other levels are composed of consumers:
- Second Trophic Level (Primary Consumers): These are herbivores that feed on producers.
- Third Trophic Level (Secondary Consumers): These organisms primarily eat primary consumers and are often carnivores.
- Fourth Trophic Level (Tertiary Consumers): These are top predators that can eat secondary consumers.
In summary, the first trophic level is essential because it supports all other levels in the food chain, making it vital for ecosystem stability and energy flow.
In an ecosystem, the food chain is organized into different trophic levels, which represent the flow of energy and nutrients. Each level consists of different types of organisms, categorized primarily based on their method of obtaining energy.
First Trophic Level: Autotrophs or Producers
The first trophic level is occupied by autotrophs, commonly known as producers. These organisms play a crucial role in the ecosystem. Here’s why:
- Definition of Autotrophs: Autotrophs are organisms that can produce their own food using sunlight (photosynthesis) or chemical energy (chemosynthesis).
- Examples: Common examples include plants, algae, and some bacteria. They convert solar energy into chemical energy, forming the base of the food web.
- Significance: By synthesizing organic compounds, they provide energy for all other trophic levels (herbivores, carnivores, etc.), establishing the foundation for the entire ecosystem.
Subsequent Trophic Levels
While the first trophic level consists of producers, the other levels are composed of consumers:
- Second Trophic Level (Primary Consumers): These are herbivores that feed on producers.
- Third Trophic Level (Secondary Consumers): These organisms primarily eat primary consumers and are often carnivores.
- Fourth Trophic Level (Tertiary Consumers): These are top predators that can eat secondary consumers.
In summary, the first trophic level is essential because it supports all other levels in the food chain, making it vital for ecosystem stability and energy flow.
Green house gases are-- a)Gases used in house for cooking
- b)Green in colour
- c)Traps solar radiations and increase temperature.
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Green house gases are-
a)
Gases used in house for cooking
b)
Green in colour
c)
Traps solar radiations and increase temperature.
d)
None of these
|
Eduskill Classes answered |
Greenhouse gases are:
- Gases used in house for cooking: This option is incorrect as greenhouse gases are not related to gases used for cooking in houses.
- Green in colour: This option is incorrect as the term "greenhouse" in greenhouse gases does not refer to the color, but rather to the concept of trapping heat.
- Traps solar radiations and increase temperature: This option is correct. Greenhouse gases are gases that absorb and emit infrared radiation within the thermal infrared range. They trap solar radiation in the Earth's atmosphere, which leads to an increase in temperature, known as the greenhouse effect.
- None of these: This option is incorrect as option C is the correct answer.
In summary, greenhouse gases are gases that trap solar radiation and increase the temperature of the Earth's atmosphere. They are not related to gases used for cooking in houses or their color.
- Gases used in house for cooking: This option is incorrect as greenhouse gases are not related to gases used for cooking in houses.
- Green in colour: This option is incorrect as the term "greenhouse" in greenhouse gases does not refer to the color, but rather to the concept of trapping heat.
- Traps solar radiations and increase temperature: This option is correct. Greenhouse gases are gases that absorb and emit infrared radiation within the thermal infrared range. They trap solar radiation in the Earth's atmosphere, which leads to an increase in temperature, known as the greenhouse effect.
- None of these: This option is incorrect as option C is the correct answer.
In summary, greenhouse gases are gases that trap solar radiation and increase the temperature of the Earth's atmosphere. They are not related to gases used for cooking in houses or their color.
According to 10% law, the energy available to each successive level is _________ of previous level- a)10%
- b)1%
- c)100%
- d)None
Correct answer is option 'A'. Can you explain this answer?
According to 10% law, the energy available to each successive level is _________ of previous level
a)
10%
b)
1%
c)
100%
d)
None
|
|
Dr Manju Sen answered |
According to the 10% law, the energy available to each successive level is 10% of the previous level.
Explanation:
- The 10% law: The 10% law is a principle in ecology that states that only 10% of the energy available at one trophic level is transferred to the next trophic level.
- Trophic levels: In an ecosystem, organisms are organized into trophic levels, which represent the different levels of the food chain. The first trophic level consists of producers (plants), followed by primary consumers, secondary consumers, and so on.
- Energy transfer: As energy flows through the food chain, it is transferred from one trophic level to another. However, not all the energy is transferred. According to the 10% law, only 10% of the energy is passed on to the next trophic level.
- Example: To illustrate the 10% law, let's consider a simple food chain. Suppose there are 1000 units of energy available at the producer level (plants). According to the 10% law:
- Only 10% (100 units) of the energy will be available to the primary consumers (herbivores) at the next trophic level.
- Then, only 10% (10 units) of the energy will be available to the secondary consumers (carnivores) at the next trophic level.
- Finally, only 10% (1 unit) of the energy will be available to the tertiary consumers (top carnivores) at the highest trophic level.
Therefore, the correct answer is A: 10%.
Choose the correctly matched pair.- a)Biotic Components - Temperature, Rainfall
- b)Abiotic Components - Wind, Soil, Minerals
- c)Natural Ecosystem - Garden, Crop-fields
- d)Human-made Ecosystem - Forests, Ponds
Correct answer is option 'B'. Can you explain this answer?
a)
Biotic Components - Temperature, Rainfall
b)
Abiotic Components - Wind, Soil, Minerals
c)
Natural Ecosystem - Garden, Crop-fields
d)
Human-made Ecosystem - Forests, Ponds
|
|
BT Educators answered |
- Option A: Biotic Components - Temperature, Rainfall
- Biotic components refer to the living organisms within an ecosystem, such as plants, animals, and microorganisms.
- Temperature and Rainfall are physical factors and thus classified as abiotic components.
- Therefore, Option A is incorrectly matched.
- Option B: Abiotic Components - Wind, Soil, Minerals
- Abiotic components include non-living physical factors that impact an ecosystem, such as Wind, Soil, and Minerals.
- Therefore, this option is correctly matched.
- Option C: Natural Ecosystem - Garden, Crop-fields
- Natural ecosystems occur naturally without human intervention and include forests, ponds, and lakes.
- Gardens and crop-fields, on the other hand, are created and maintained by humans, making them human-made (artificial) ecosystems.
- Therefore, Option C is incorrectly matched.
- Option D: Human-made Ecosystem - Forests, Ponds
- Forests and ponds are examples of natural ecosystems.
- Human-made ecosystems include those altered or created by human activity, such as gardens and crop-fields.
- Therefore, Option D is incorrectly matched.
- Thus, the correctly matched pair is Option B: Abiotic Components - Wind, Soil, Minerals.
Micro-organisms belongs to the group of-- a)Decomposers
- b)Producers
- c)Consumers
- d)None of the above
Correct answer is option 'A'. Can you explain this answer?
Micro-organisms belongs to the group of-
a)
Decomposers
b)
Producers
c)
Consumers
d)
None of the above
|
Master Training Institute answered |
Micro-organisms belong to the group of decomposers.
In conclusion, micro-organisms are a group of decomposers that play a vital role in the ecosystem by breaking down organic matter and recycling nutrients. They are found in various environments and are essential for maintaining the balance of nature.
- Micro-organisms are small, single-celled organisms that are not visible to the naked eye.
- They play a crucial role in the ecosystem by breaking down organic matter and recycling nutrients.
- Decomposers, such as bacteria and fungi, are responsible for the process of decomposition.
- Decomposition is the breakdown of dead plants and animals into simpler substances, which can then be used by other organisms.
- Micro-organisms secrete enzymes that help in the breakdown of complex organic molecules into simpler compounds.
- They obtain their energy by breaking down organic matter.
- Micro-organisms are found in various environments, such as soil, water, and even inside the bodies of other organisms.
- They are essential for the nutrient cycling in ecosystems and help in maintaining the balance of nature.
- Examples of micro-organisms that act as decomposers include bacteria, fungi, and certain types of protozoa.
In conclusion, micro-organisms are a group of decomposers that play a vital role in the ecosystem by breaking down organic matter and recycling nutrients. They are found in various environments and are essential for maintaining the balance of nature.
How can we recycle plastic?- a)Throw it in the ocean
- b)Heat it to make new products
- c)Use it to feed animals
- d)Store it in landfills
Correct answer is option 'B'. Can you explain this answer?
a)
Throw it in the ocean
b)
Heat it to make new products
c)
Use it to feed animals
d)
Store it in landfills
|
Kds Coaching answered |
Recycling plastic involves heating it to create new products like buckets, bags, and chairs.
Which of the following constitute a food chain ?- a)Goat, cow and elephant
- b)Grass, goat and human
- c)Grass, fish and goat.
- d)Grass, wheat and mango.
Correct answer is option 'B'. Can you explain this answer?
Which of the following constitute a food chain ?
a)
Goat, cow and elephant
b)
Grass, goat and human
c)
Grass, fish and goat.
d)
Grass, wheat and mango.
|
|
Eduskill Classes answered |
Food Chain Explanation:
A food chain represents the transfer of energy and nutrients from one organism to another in an ecosystem. It consists of a sequence of organisms, each serving as a source of food for the next organism. Let's analyze the options given:
Option A:
- Goat, cow, and elephant: While these organisms can coexist in an ecosystem, they do not form a food chain as they are not directly linked in terms of energy transfer from one to another.
Option B:
- Grass, goat, and human: This forms a food chain as it represents the flow of energy and nutrients. Grass is consumed by the goat, and the goat serves as food for humans.
Option C:
- Grass, fish, and goat: This does not form a food chain as there is no direct connection between grass and fish. The goat is not involved in the energy transfer between grass and fish.
Option D:
- Grass, wheat, and mango: This also does not form a food chain as there is no direct connection between grass and mango. Wheat is not involved in the energy transfer between these organisms.
Therefore, the correct answer is Option B: Grass, goat, and human, as it represents a food chain where energy and nutrients flow from grass to goat and then to humans.
A food chain represents the transfer of energy and nutrients from one organism to another in an ecosystem. It consists of a sequence of organisms, each serving as a source of food for the next organism. Let's analyze the options given:
Option A:
- Goat, cow, and elephant: While these organisms can coexist in an ecosystem, they do not form a food chain as they are not directly linked in terms of energy transfer from one to another.
Option B:
- Grass, goat, and human: This forms a food chain as it represents the flow of energy and nutrients. Grass is consumed by the goat, and the goat serves as food for humans.
Option C:
- Grass, fish, and goat: This does not form a food chain as there is no direct connection between grass and fish. The goat is not involved in the energy transfer between grass and fish.
Option D:
- Grass, wheat, and mango: This also does not form a food chain as there is no direct connection between grass and mango. Wheat is not involved in the energy transfer between these organisms.
Therefore, the correct answer is Option B: Grass, goat, and human, as it represents a food chain where energy and nutrients flow from grass to goat and then to humans.
Ozone shields the surface of the earth from ______ radiation from the Sun.- a)Harmful
- b)Ultraviolet (UV)
- c)Infrared
- d)Visible
Correct answer is option 'B'. Can you explain this answer?
Ozone shields the surface of the earth from ______ radiation from the Sun.
a)
Harmful
b)
Ultraviolet (UV)
c)
Infrared
d)
Visible
|
Ias Masters answered |
Ozone shields the surface of the earth from ultraviolet (UV) radiation from the Sun. UV radiation can be harmful to organisms, and ozone plays a crucial role in protecting life on Earth from its adverse effects.
Choose the correctly matched pair.- a)Ozone - Greenhouse Gas
- b)Plastic - Biodegradable
- c)Chlorofluorocarbons (CFCs) - Ozone Depletion
- d)Ultraviolet (UV) Radiation - Harmless to Humans
Correct answer is option 'C'. Can you explain this answer?
a)
Ozone - Greenhouse Gas
b)
Plastic - Biodegradable
c)
Chlorofluorocarbons (CFCs) - Ozone Depletion
d)
Ultraviolet (UV) Radiation - Harmless to Humans
|
K.L Institute answered |
- Option A: Ozone - Greenhouse Gas Ozone is not primarily categorized as a greenhouse gas. While it does have some greenhouse properties, its main environmental significance lies in its role in the stratosphere, where it protects Earth from harmful ultraviolet (UV) radiation. Thus, this pair is incorrectly matched.
- Option B: Plastic - Biodegradable Most plastics are non-biodegradable, meaning they do not break down easily by natural processes. This characteristic leads to long-term environmental pollution. Thus, this pair is incorrectly matched.
- Option C: Chlorofluorocarbons (CFCs) - Ozone Depletion Chlorofluorocarbons (CFCs) are synthetic chemicals that have been shown to deplete the ozone layer in the stratosphere. They release chlorine atoms when exposed to UV radiation, which then break down ozone molecules, leading to ozone layer thinning. This pair is correctly matched.
- Option D: Ultraviolet (UV) Radiation - Harmless to Humans Ultraviolet (UV) radiation is harmful to humans and can cause skin cancer, cataracts, and other health issues. It is precisely because of this harm that the ozone layer's protective role is so crucial. Thus, this pair is incorrectly matched.
Which of the following is biodegradable-- a)Plastic
- b)Paper
- c)Polythene
- d)Aluminium foil
Correct answer is option 'B'. Can you explain this answer?
Which of the following is biodegradable-
a)
Plastic
b)
Paper
c)
Polythene
d)
Aluminium foil
|
EduRev Class 10 answered |
Biodegradable Materials
- Paper: Paper is derived from plant fibers and is one of the most common biodegradable materials. It decomposes naturally over time when exposed to the environment.
Non-biodegradable Materials
- Plastic: Plastic is a synthetic material that is not easily broken down by natural processes. It can persist in the environment for hundreds of years.
- Polythene: Polythene, also known as polyethylene, is a type of plastic that is non-biodegradable.
- Aluminium foil: Aluminium foil is a metal material that is not biodegradable. It does not decompose naturally and can take a long time to break down.
Therefore, the only biodegradable material among the given options is paper.
Montreal protocol became effective in-- a)1987
- b)1988
- c)1985
- d)1972
Correct answer is option 'A'. Can you explain this answer?
Montreal protocol became effective in-
a)
1987
b)
1988
c)
1985
d)
1972
|
|
K.L Institute answered |
Montreal Protocol Effective Date
The Montreal Protocol, an international environmental treaty designed to protect the ozone layer, became effective in 1989. The protocol was adopted on September 16, 1987, and entered into force on January 1, 1989. It has since been ratified by almost all countries around the world.
Details:
Here are some key points about the effective date of the Montreal Protocol:
Adoption: The Montreal Protocol was adopted on September 16, 1987, during a conference held in Montreal, Canada.
Effective Date: The protocol became effective on January 1, 1989, marking the official start of its implementation.
Objective: The primary objective of the Montreal Protocol is to phase out the production and use of substances that deplete the ozone layer, such as chlorofluorocarbons (CFCs) and halons.
Success: The Montreal Protocol is considered one of the most successful international environmental agreements. It has led to a significant reduction in the production and consumption of ozone-depleting substances globally.
Amendments: Over the years, the protocol has been amended several times to strengthen its provisions and address emerging ozone-depleting substances. These amendments include the London Amendment (1990), Copenhagen Amendment (1992), and Beijing Amendment (1999).
The Montreal Protocol serves as a crucial framework for international cooperation in protecting the ozone layer and has played a significant role in preventing further depletion.
The Montreal Protocol, an international environmental treaty designed to protect the ozone layer, became effective in 1989. The protocol was adopted on September 16, 1987, and entered into force on January 1, 1989. It has since been ratified by almost all countries around the world.
Details:
Here are some key points about the effective date of the Montreal Protocol:
The Montreal Protocol serves as a crucial framework for international cooperation in protecting the ozone layer and has played a significant role in preventing further depletion.
Assertion (A): In an ecosystem, the autotrophs are positioned at the first trophic level.Reason (R): Autotrophs convert solar energy into chemical energy that is utilized by heterotrophs and decomposers.- a)If both Assertion and Reason are true and Reason is the correct explanation of Assertion
- b)If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
- c)If Assertion is true but Reason is false
- d)If both Assertion and Reason are false
Correct answer is option 'A'. Can you explain this answer?
Assertion (A): In an ecosystem, the autotrophs are positioned at the first trophic level.
Reason (R): Autotrophs convert solar energy into chemical energy that is utilized by heterotrophs and decomposers.
a)
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
b)
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c)
If Assertion is true but Reason is false
d)
If both Assertion and Reason are false
|
|
K.L Institute answered |
- The assertion is correct. Autotrophs, such as green plants, occupy the first trophic level in an ecosystem as they are capable of converting solar energy into chemical energy through photosynthesis.
- The reason is also correct. Autotrophs play a fundamental role in capturing solar energy and converting it into a form that can be utilized by heterotrophs (consumers) and decomposers within the ecosystem.
- Therefore, in this context, Option A is the correct answer as both the Assertion and Reason are true, and the Reason provides a valid explanation for the Assertion.
What does the term "urban" refer to?- a)Rural areas
- b)Villages
- c)Cities and towns
- d)Agricultural fields
Correct answer is option 'C'. Can you explain this answer?
a)
Rural areas
b)
Villages
c)
Cities and towns
d)
Agricultural fields
|
|
Stoneridge Institute answered |
"Urban" refers to areas related to cities and towns, where population density is higher than rural areas.
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