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All questions of Our Environment for Class 10 Exam
Depletion of ozone is mainly due to- a)chlorofluorocarbon compounds
- b)carbon monoxide
- c)methane
- d)pesticides
Correct answer is option 'A'. Can you explain this answer?
Depletion of ozone is mainly due to
a)
chlorofluorocarbon compounds
b)
carbon monoxide
c)
methane
d)
pesticides
|
Rahul tiwari answered |
Depletion of ozone layer is mainly due to chlorofluorocarbon compounds.
Which of the following is not a biotic component of an ecosystem ?- a)Rainfall
- b)Plants
- c)Animals
- d)Human beings
Correct answer is option 'A'. Can you explain this answer?
Which of the following is not a biotic component of an ecosystem ?
a)
Rainfall
b)
Plants
c)
Animals
d)
Human beings
|
Amit Kumar answered |
Rainfall is not a living organism
Which of the following is not biodegradable ?- a)Grass
- b)Plastic bag
- c)Paper
- d)Wood
Correct answer is option 'B'. Can you explain this answer?
Which of the following is not biodegradable ?
a)
Grass
b)
Plastic bag
c)
Paper
d)
Wood
|
Krishna Iyer answered |
Plastic bags are synthetic materials. These are not degraded by bacteria.
Which one of the following is an artificial ecosystem ?- a)Pond
- b)Crop field
- c)Lake
- d)Forest
Correct answer is option 'B'. Can you explain this answer?
Which one of the following is an artificial ecosystem ?
a)
Pond
b)
Crop field
c)
Lake
d)
Forest
|
|
Krishna Iyer answered |
Crop field is an artificial ecosystem.
Every food chain in the ecosystem begins with………. which are the original source of food.- a)Saprophytes
- b)Parasites
- c)Producers
- d)Herbivores
Correct answer is option 'C'. Can you explain this answer?
Every food chain in the ecosystem begins with………. which are the original source of food.
a)
Saprophytes
b)
Parasites
c)
Producers
d)
Herbivores
|
|
Amit Kumar answered |
All green plants and few blue-green algae which can produce food by photosynthesis are called the producers.
In a food chain, the third trophic level is always occupied by- a)carnivores
- b)herbivores
- c)decomposers v
- d)producers
Correct answer is option 'A'. Can you explain this answer?
In a food chain, the third trophic level is always occupied by
a)
carnivores
b)
herbivores
c)
decomposers v
d)
producers
|
Gaurav Kumar answered |
The third trophic level in a food chain is always occupied by carnivores.
In a given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level ?
Grass → Grasshopper → Frog → Snake → Hawk
- a)5 kJ
- b)50 kJ
- c)500 kJ
- d)5000 kJ
Correct answer is option 'D'. Can you explain this answer?
In a given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level ?
Grass → Grasshopper → Frog → Snake → Hawk
Grass → Grasshopper → Frog → Snake → Hawk
a)
5 kJ
b)
50 kJ
c)
500 kJ
d)
5000 kJ
|
Surbhi Gupta answered |
According to 10 percent law, 90% of the energy captured from the previous trophic level is lost to the environment and only 10 percent is made available to the next trophic level.
In this food chain, at the 4th trophic level, 5 kJ energy is available to the snake
⇒ Energy available to Frog = 10% of 50 kJ
⇒ Energy available to Grasshopper = 10% of 500 kJ
⇒ Energy available to Grass = 10% of 5000 kJ.
A food chain comprising birds, green plants, fish and man. The concentration of harmful chemical entering the food chain will be maximum in- a)green plants
- b)man
- c)birds
- d)fish
Correct answer is option 'B'. Can you explain this answer?
A food chain comprising birds, green plants, fish and man. The concentration of harmful chemical entering the food chain will be maximum in
a)
green plants
b)
man
c)
birds
d)
fish
|
|
Avinash Patel answered |
- A food chain comprising birds, green plants, fish and man.
- Food chain in ecology, the sequence of transfers of matter and energy in the form of food from one organism to another organism.
- Food chains intervined locally into a food web because most organisms consume more than one type of animal or plant.
- Each level of a food chain represents a different trophic level.
- Humans are to be present at the top of the food chain because they eat all kinds of plants and animals.
- The human food chain starts with plants.
- Humans are dominant consumers.
- They affect food webs through energy production and agriculture, pollution, habitat destruction, overfishing and hunting it affect both soil and aquatic ecosystem.
Which group of organisms are not constituents of a food chain?
(i) Grass, lion, rabbit, wolf
(ii) Plankton, man, fish, grasshopper
(iii) Wolf, grass, snake, tiger
(iv) Frog, snake, eagle, grass, grasshopper- a)(i) and (ii)
- b)(iii) and (iv)
- c)(ii) and (iii)
- d)(i) and (iv)
Correct answer is option 'C'. Can you explain this answer?
Which group of organisms are not constituents of a food chain?
(i) Grass, lion, rabbit, wolf
(ii) Plankton, man, fish, grasshopper
(iii) Wolf, grass, snake, tiger
(iv) Frog, snake, eagle, grass, grasshopper
(i) Grass, lion, rabbit, wolf
(ii) Plankton, man, fish, grasshopper
(iii) Wolf, grass, snake, tiger
(iv) Frog, snake, eagle, grass, grasshopper
a)
(i) and (ii)
b)
(iii) and (iv)
c)
(ii) and (iii)
d)
(i) and (iv)
|
|
Krishna Iyer answered |
The organisms in an ecosystem are related through food requirements. This relationship is called food chain. In option (i) grass is eaten by rabbit, rabbit is consumed by wolf and lion eats wolf. In option (iv) grasshopper eats grass, frog eats grasshopper, snake eats frog and eagle consumes snake. In option (ii) grasshopper is found in terrestrial ecosystems not aquatic ecosystems. In option (iii) there is no herbivore animal to consume grass. Thus, the correct answer is option C.
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
|
K.L Institute answered |
- Assertion: In this scenario, the Assertion is correct as it highlights the interaction and balance maintenance in nature by various organisms.
- Reason: The Reason is also accurate, explaining the components of an ecosystem. However, the Reason is not a direct explanation of the Assertion; rather, it provides additional information about what constitutes an ecosystem. Hence, the correct answer is Option B.
Which of the following statements about food chain and energy flow through ecosystem is false?- a)Food webs include two or more food chains
- b)All organisms that are not producers are consumers
- c)A single organism can feed at several trophic levels
- d)Detritivores feed at all trophic levels except the producer level
- e)The lower the trophic level at which an organism feeds, the more energy available
Correct answer is option 'D'. Can you explain this answer?
Which of the following statements about food chain and energy flow through ecosystem is false?
a)
Food webs include two or more food chains
b)
All organisms that are not producers are consumers
c)
A single organism can feed at several trophic levels
d)
Detritivores feed at all trophic levels except the producer level
e)
The lower the trophic level at which an organism feeds, the more energy available
|
|
Gaurav Kumar answered |
There are many food chains which are interconnected to form the food web and so one organism can feed at different trophic levels in the different food chain. There is a 0gradual decrease in the energy of the increasing trophic levels due to the loss of energy with each transfer. The producers are the organisms which can synthesize food and the organisms which feed on the other sources are known as consumers. The detrivores are the organisms which feed on the dead matter of the organisms which belong to all the trophic levels.
Excessive exposure of humans to UV rays results in
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcers- a)(i) and (ii)
- b)(ii) and (iv)
- c)(i) and (iii)
- d)(iii) and (iv)
Correct answer is option 'C'. Can you explain this answer?
Excessive exposure of humans to UV rays results in
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcers
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcers
a)
(i) and (ii)
b)
(ii) and (iv)
c)
(i) and (iii)
d)
(iii) and (iv)
|
Madara Uchiha answered |
UV Rays as the name suggests Ultra Violent rays causes a lot of harm to our body and to our environment like :-
1. temporary/permanent blindness
2. skin cancer
3. faster evaporation of water which leads to drying of leaves(Forest Fire)
4. infrastructural damage
and so on
Excessive exposure of humans to UV-rays results in
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcer- a)(i) and (ii)
- b)(ii) and (iv)
- c)(i) and (iii)
- d)(iii) and (iv)
Correct answer is option 'C'. Can you explain this answer?
Excessive exposure of humans to UV-rays results in
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcer
(i) damage to immune system
(ii) damage to lungs
(iii) skin cancer
(iv) peptic ulcer
a)
(i) and (ii)
b)
(ii) and (iv)
c)
(i) and (iii)
d)
(iii) and (iv)
|
|
Gaurav Kumar answered |
UV rays or ultraviolet rays can affect human health in many ways like causing skin cancer or weakening immune system. Excessive exposure to UV rays can lead to skin cancer because the UV rays cause damage to the DNA in skin cells.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Garden is an artificial ecosystem.Reason : Biotic and abiotic components are manipulated by humans.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Garden is an artificial ecosystem.
Reason : Biotic and abiotic components are manipulated by humans.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Kiran Mehta answered |
Crop fields are man made and some biotic and abiotic components are manipulated by humans. Artificial ecosystems are those ecosystems which are modified and managed by human beings.
Crop fields are man-made, plants do not grow naturally; rather , most of the plants are grown by humans according to the season, type of soil, etc. Crop fields are not like wild forest areas which are left to the care of nature and can sustain themselves.
In crop fields, the land is managed, soil is prepared for sowing seeds, then irrigated and further progress is also kept under observation for getting good yield.
Thus, crop fields are known as artificial ecosystems.
In the garden ecosystem, which of the following are producers?- a)Insects
- b)Snakes
- c)Grasses
- d)Rabbits
Correct answer is option 'C'. Can you explain this answer?
In the garden ecosystem, which of the following are producers?
a)
Insects
b)
Snakes
c)
Grasses
d)
Rabbits
|
|
Hitakshi 💞💞 answered |
Green plants (grasses) are autotrophic. They perform photosynthesis by using solar energy to synthesize their own food. Hence they are the producers in an ecosystem.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Supersonic jets cause pollution as they thin out ozone.Reason : Depletion of ozone causes greenhouse effect.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Supersonic jets cause pollution as they thin out ozone.
Reason : Depletion of ozone causes greenhouse effect.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
Raghav Bansal answered |
90% of naturally occurring atmospheric ozone occurs in the stratosphere. Stratospheric ozone is very important, it removes almost all incoming UVA, and 70% of the incoming UVB at equator, 90% at poles. All aircraft produce water, CO2, CO etc. in exhaust gases. Most commercial flights are confined to the troposphere, but high-level supersonic aircraft inject pollutants into the stratosphere, which leads to the thinning of the ozone layer. Of these nitrogen oxides are especially harmful.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Decomposers keep the environment clean.Reason : They recycle matter by breaking down the organic remains and waste products of plants and animals.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Decomposers keep the environment clean.
Reason : They recycle matter by breaking down the organic remains and waste products of plants and animals.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Aditya Shah answered |
Decomposers keep the environment clean by decomposing or consuming the dead remains of other organisms.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Aquatic f o o d chain is the food chain present in water bodies.Reason : The example of an aquatic food chain is phytoplankton → zooplankton → fish → shark.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Aquatic f o o d chain is the food chain present in water bodies.
Reason : The example of an aquatic food chain is phytoplankton → zooplankton → fish → shark.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
Pooja Shah answered |
Aquatic food chain is the food chain present in water bodies, e.g. phytoplankton → zooplankton → fish → shark
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Biotic components of the ecosystem continuously require energy to carry on life processes.Reason : Abiotic components are the nonliving factors of the ecosystem.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'B'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Biotic components of the ecosystem continuously require energy to carry on life processes.
Reason : Abiotic components are the nonliving factors of the ecosystem.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Sarita iyer answered |
Assertion: Biotic components of the ecosystem continuously require energy to carry on life processes.
Reason: Abiotic components are the nonliving factors of the ecosystem.
The correct answer is option B.
Explanation:
Biotic Components Require Energy:
- The biotic components of an ecosystem include all living organisms such as plants, animals, and microorganisms.
- These organisms require energy to carry out various life processes such as growth, reproduction, movement, and metabolism.
- Energy is obtained through various sources such as sunlight, organic matter, or other organisms.
- Green plants, for example, use sunlight to carry out photosynthesis and convert it into chemical energy in the form of glucose.
- Animals, on the other hand, obtain energy by consuming plants or other animals.
Abiotic Components of Ecosystem:
- Abiotic components are the nonliving factors of an ecosystem.
- They include physical and chemical factors such as sunlight, temperature, water, air, soil, and minerals.
- These factors provide the necessary conditions for the survival and functioning of the biotic components.
- While abiotic components do not require energy for their own life processes, they play a crucial role in determining the availability of resources and environmental conditions for the biotic components.
Relationship between Assertion and Reason:
- The assertion states that biotic components of the ecosystem continuously require energy to carry on life processes, which is true.
- The reason states that abiotic components are the nonliving factors of the ecosystem, which is also true.
- However, the reason does not provide a direct explanation for why biotic components require energy.
- The reason simply provides additional information about the nature of abiotic components and their role in the ecosystem.
- The requirement of energy by biotic components is primarily due to their physiological processes and the need to maintain their biological functions.
Therefore, both the assertion and reason are true, but the reason is not the correct explanation of the assertion. Hence, option B is the correct answer.
Reason: Abiotic components are the nonliving factors of the ecosystem.
The correct answer is option B.
Explanation:
Biotic Components Require Energy:
- The biotic components of an ecosystem include all living organisms such as plants, animals, and microorganisms.
- These organisms require energy to carry out various life processes such as growth, reproduction, movement, and metabolism.
- Energy is obtained through various sources such as sunlight, organic matter, or other organisms.
- Green plants, for example, use sunlight to carry out photosynthesis and convert it into chemical energy in the form of glucose.
- Animals, on the other hand, obtain energy by consuming plants or other animals.
Abiotic Components of Ecosystem:
- Abiotic components are the nonliving factors of an ecosystem.
- They include physical and chemical factors such as sunlight, temperature, water, air, soil, and minerals.
- These factors provide the necessary conditions for the survival and functioning of the biotic components.
- While abiotic components do not require energy for their own life processes, they play a crucial role in determining the availability of resources and environmental conditions for the biotic components.
Relationship between Assertion and Reason:
- The assertion states that biotic components of the ecosystem continuously require energy to carry on life processes, which is true.
- The reason states that abiotic components are the nonliving factors of the ecosystem, which is also true.
- However, the reason does not provide a direct explanation for why biotic components require energy.
- The reason simply provides additional information about the nature of abiotic components and their role in the ecosystem.
- The requirement of energy by biotic components is primarily due to their physiological processes and the need to maintain their biological functions.
Therefore, both the assertion and reason are true, but the reason is not the correct explanation of the assertion. Hence, option B is the correct answer.
If a grasshopper is eaten by a frog, then the energy transfer will be from- a)producer to decomposer
- b)producer to primary consumer
- c)primary consumer to secondary consumer
- d)secondary consumer to primary consumer
Correct answer is option 'C'. Can you explain this answer?
If a grasshopper is eaten by a frog, then the energy transfer will be from
a)
producer to decomposer
b)
producer to primary consumer
c)
primary consumer to secondary consumer
d)
secondary consumer to primary consumer
|
|
Karan sethi answered |
The energy transfer will be from c) primary consumer to secondary consumer.
Explanation: In a food chain, energy is transferred from one trophic level to another as organisms consume other organisms. A grasshopper, being an herbivore, feeds on plants (producers) making it a primary consumer. A frog, on the other hand, is a carnivore that feeds on other animals, such as grasshoppers, making it a secondary consumer. When a frog eats a grasshopper, the energy stored in the grasshopper's body is transferred to the frog, thus the transfer is from primary consumer (grasshopper) to the secondary consumer (frog).
Explanation: In a food chain, energy is transferred from one trophic level to another as organisms consume other organisms. A grasshopper, being an herbivore, feeds on plants (producers) making it a primary consumer. A frog, on the other hand, is a carnivore that feeds on other animals, such as grasshoppers, making it a secondary consumer. When a frog eats a grasshopper, the energy stored in the grasshopper's body is transferred to the frog, thus the transfer is from primary consumer (grasshopper) to the secondary consumer (frog).
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Decomposers act as cleaning agents of the environment.Reason : The decomposers recycle waste material in the hydrosphere.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Decomposers act as cleaning agents of the environment.
Reason : The decomposers recycle waste material in the hydrosphere.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Anita Menon answered |
Organisms which break down the complex organic compounds present in dead and decaying matter are called decomposers, e.g., certain bacteria and fungi. Decomposers act as cleaning agents of the environment by decomposing the dead bodies of plants and animals. They also help in recycling of materials, replenishment of soil's nutrients etc. The consequence of their absence in an ecosystem can be disastrous as discussed below
(i) The dead bodies would keep lying, it would lead to their accumulation and thus, polluting the environment.
(ii) The elements by which bodies are made would never be returned to the environment. As a result, all the nutrients present in soil, air and water would soon be exhausted and the whole life cycle of organisms will be disrupted.
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.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Ozone is both beneficial and damaging.Reason : Stop the release of chlorofluorocarbons to protect the ozone.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'B'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Ozone is both beneficial and damaging.
Reason : Stop the release of chlorofluorocarbons to protect the ozone.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
Ishan Choudhury answered |
Ozone is damaging as it is a deadly poison. It is beneficial as it shields the surface of the earth from UV radiations of the Sun. We should stop the release of Chlorofluorocarbons (CFCs) to protect the ozone.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : A biotic component of an ecosystem involves cycling of material and flow of energy.Reason : This is essential to keep biotic factors alive.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : A biotic component of an ecosystem involves cycling of material and flow of energy.
Reason : This is essential to keep biotic factors alive.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
Meera Rana answered |
The assertion is correct because plants can synthesize food due to the presence of abiotic components like carbon dioxide and sunlight, due to which energy is produced. This energy is transferred at each trophic level.
The reason is correct because due to energy obtained, organisms at each trophic level sustain.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Ecology is the study of the relationship between living organisms and their environment.Reason : The biotic community and non-living environment of an area function together to form an ecosystem.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Ecology is the study of the relationship between living organisms and their environment.
Reason : The biotic community and non-living environment of an area function together to form an ecosystem.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Rohit Sharma answered |
All the interacting organisms in an area together with the non-living constituents of the environment form an ecosystem. Thus, an ecosystem consists of biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil and minerals.
Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the- a)food web
- b)ecological pyramid
- c)ecosystem
- d)food chain
Correct answer is option 'A'. Can you explain this answer?
Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the
a)
food web
b)
ecological pyramid
c)
ecosystem
d)
food chain
|
Khusboo jain answered |
Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the food web.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion: Herbivores are called first order consumers.Reason : Tiger is a top carnivore.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'B'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Herbivores are called first order consumers.
Reason : Tiger is a top carnivore.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Amit Kumar answered |
Herbivores obtain their food from plants. Hence, they are known as first order carnivores. The carnivores like tigers cannot be preyed upon further, lie at the top of the food chain and hence termed as top carnivores.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : A network of food chains existing together in an ecosystem is known as the food web.Reason : An animal like a kite cannot be a part of a food web.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'C'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : A network of food chains existing together in an ecosystem is known as the food web.
Reason : An animal like a kite cannot be a part of a food web.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Ishaani mehta answered |
Assertion: A network of food chains existing together in an ecosystem is known as the food web.
Reason: An animal like a kite cannot be a part of a food web.
The correct answer for this question is option 'C'.
Explanation:
To understand why option 'C' is the correct answer, let's break down the assertion and reason given in the question.
Assertion: A network of food chains existing together in an ecosystem is known as the food web.
- This statement is true. A food web is a complex network of interconnected food chains that shows the flow of energy and nutrients in an ecosystem. It represents the feeding relationships between different organisms in the ecosystem.
Reason: An animal like a kite cannot be a part of a food web.
- This statement is false. An animal like a kite can indeed be a part of a food web. In a food web, organisms are interconnected through feeding relationships. Each organism occupies a specific trophic level and interacts with multiple other organisms as both predator and prey. A kite, for example, can be a predator that feeds on smaller animals like rodents or insects and can also be preyed upon by larger predators like eagles or owls. Thus, it is an integral part of the food web.
Therefore, while the assertion is true, the reason provided is false. This is why option 'C' is the correct answer.
Reason: An animal like a kite cannot be a part of a food web.
The correct answer for this question is option 'C'.
Explanation:
To understand why option 'C' is the correct answer, let's break down the assertion and reason given in the question.
Assertion: A network of food chains existing together in an ecosystem is known as the food web.
- This statement is true. A food web is a complex network of interconnected food chains that shows the flow of energy and nutrients in an ecosystem. It represents the feeding relationships between different organisms in the ecosystem.
Reason: An animal like a kite cannot be a part of a food web.
- This statement is false. An animal like a kite can indeed be a part of a food web. In a food web, organisms are interconnected through feeding relationships. Each organism occupies a specific trophic level and interacts with multiple other organisms as both predator and prey. A kite, for example, can be a predator that feeds on smaller animals like rodents or insects and can also be preyed upon by larger predators like eagles or owls. Thus, it is an integral part of the food web.
Therefore, while the assertion is true, the reason provided is false. This is why option 'C' is the correct answer.
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
|
|
Maulik Ghoshal answered |
Understanding the 10% Rule
The 10% Rule is a fundamental concept in ecology that describes the efficiency of energy transfer in an ecosystem.
Energy Transfer Between Trophic Levels
- In a typical food chain, energy is transferred from one trophic level to the next.
- Only about 10% of the energy from one level is passed on to the next level.
- This phenomenon occurs due to energy losses through metabolic processes such as respiration, movement, and heat.
Importance of the 10% Rule
- The 10% Rule highlights the inefficiency of energy transfer in ecosystems, emphasizing that only a fraction of energy is available to higher trophic levels.
- For example, if a plant (producer) captures 1000 calories of energy from the sun, only about 100 calories will be available to the herbivore (primary consumer) that eats it, and merely 10 calories will be available to the carnivore (secondary consumer) that eats the herbivore.
Implications on Ecosystem Structure
- The limitation imposed by the 10% Rule affects the number of trophic levels in an ecosystem.
- It explains why food chains are typically short, as significant energy loss restricts the number of levels that can be sustained.
Conclusion
The correct answer is option 'A' because it accurately reflects the principle of energy transfer in ecological systems, emphasizing that only about 10% of energy is passed to the next trophic level. Understanding this rule is crucial for studying energy dynamics and the structure of ecosystems.
The 10% Rule is a fundamental concept in ecology that describes the efficiency of energy transfer in an ecosystem.
Energy Transfer Between Trophic Levels
- In a typical food chain, energy is transferred from one trophic level to the next.
- Only about 10% of the energy from one level is passed on to the next level.
- This phenomenon occurs due to energy losses through metabolic processes such as respiration, movement, and heat.
Importance of the 10% Rule
- The 10% Rule highlights the inefficiency of energy transfer in ecosystems, emphasizing that only a fraction of energy is available to higher trophic levels.
- For example, if a plant (producer) captures 1000 calories of energy from the sun, only about 100 calories will be available to the herbivore (primary consumer) that eats it, and merely 10 calories will be available to the carnivore (secondary consumer) that eats the herbivore.
Implications on Ecosystem Structure
- The limitation imposed by the 10% Rule affects the number of trophic levels in an ecosystem.
- It explains why food chains are typically short, as significant energy loss restricts the number of levels that can be sustained.
Conclusion
The correct answer is option 'A' because it accurately reflects the principle of energy transfer in ecological systems, emphasizing that only about 10% of energy is passed to the next trophic level. Understanding this rule is crucial for studying energy dynamics and the structure of ecosystems.
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
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Polythene bags and plastic containers are non-biodegradable substances.Reason: They can be broken down by microorganisms in natural simple harmless substances.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'C'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Polythene bags and plastic containers are non-biodegradable substances.
Reason: They can be broken down by microorganisms in natural simple harmless substances.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Aditya Shah answered |
Substances like polythene bags and plastics are non- biodegradable because they cannot be broken down by micro-organisms into simpler harmless substances in nature. Substances that can be broken down by microorganisms in natural simple harmless substances are biodegradable substances.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : The crown fires are most destructive as they burn the tree top.Reason : Due to crown fire the temperature of that area may rise upto 700°C.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : The crown fires are most destructive as they burn the tree top.
Reason : Due to crown fire the temperature of that area may rise upto 700°C.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Aditya Shah answered |
Crown files are most destructive. These destroy the canopies of trees and entire vegetational cover of that particular area. Due to this fire, the temperature rises upto 700°C and may adversely affect the vegetation.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion :Praying mantis is green in colour which merges with plant foliage.
Reason : Animals adopt different strategies to survive in hostile environment.
- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion :Praying mantis is green in colour which merges with plant foliage.
Reason : Animals adopt different strategies to survive in hostile environment.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Aditya Shah answered |
Animals blend with the surroundings or background to remain unnoticed for protection and aggression.
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.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Flow of energy in a food chain is unidirectional.Reason : Energy captured by autotrophs does not revert back to the solar input and it passes to the herbivores.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Flow of energy in a food chain is unidirectional.
Reason : Energy captured by autotrophs does not revert back to the solar input and it passes to the herbivores.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Aarush srinivasan answered |
Explanation:
Flow of Energy in a Food Chain:
- In a food chain, energy flows from one trophic level to the next.
- The flow of energy is unidirectional, meaning it moves in one direction only.
Energy Transfer in Food Chain:
- Autotrophs (producers) capture solar energy through photosynthesis and convert it into chemical energy.
- This energy is then passed on to herbivores (primary consumers) when they consume autotrophs.
- The energy captured by autotrophs does not revert back to the solar input; instead, it moves through the food chain to higher trophic levels.
Assertion and Reason Analysis:
- The assertion that the flow of energy in a food chain is unidirectional is true.
- The reason provided, that energy captured by autotrophs does not revert back to the solar input and passes to herbivores, correctly explains why the flow of energy is unidirectional.
Therefore, option 'A' is the correct choice as both the assertion and reason are true, and the reason is the correct explanation for the assertion.
Flow of Energy in a Food Chain:
- In a food chain, energy flows from one trophic level to the next.
- The flow of energy is unidirectional, meaning it moves in one direction only.
Energy Transfer in Food Chain:
- Autotrophs (producers) capture solar energy through photosynthesis and convert it into chemical energy.
- This energy is then passed on to herbivores (primary consumers) when they consume autotrophs.
- The energy captured by autotrophs does not revert back to the solar input; instead, it moves through the food chain to higher trophic levels.
Assertion and Reason Analysis:
- The assertion that the flow of energy in a food chain is unidirectional is true.
- The reason provided, that energy captured by autotrophs does not revert back to the solar input and passes to herbivores, correctly explains why the flow of energy is unidirectional.
Therefore, option 'A' is the correct choice as both the assertion and reason are true, and the reason is the correct explanation for the assertion.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : First trophic level in a food chain is always a green plant.Reason : Green plants are called producers.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : First trophic level in a food chain is always a green plant.
Reason : Green plants are called producers.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Arun Sharma answered |
Green plants are producers. The first trophic level in a food chain is a producer i.e. those organisms which produce food by photosynthesis.
First link in any food chain is usually green plants because- a)they are widely distributed
- b)they are fixed at one place in the soil
- c)they alone have the capacity to synthesise food using sunlight
- d)there are more herbivores than carnivores
Correct answer is option 'C'. Can you explain this answer?
First link in any food chain is usually green plants because
a)
they are widely distributed
b)
they are fixed at one place in the soil
c)
they alone have the capacity to synthesise food using sunlight
d)
there are more herbivores than carnivores
|
Crafty Classes answered |
Why are green plants usually the first link in any food chain?
Green plants are usually the first link in any food chain because:
- Capacity to synthesize food: Green plants are the primary producers in an ecosystem. They have the ability to synthesize their food through a process called photosynthesis, using sunlight, water, and carbon dioxide. This allows them to convert solar energy into chemical energy in the form of glucose.
- Provide energy: Green plants serve as a source of energy for other organisms in the food chain. They convert sunlight energy into organic matter, which is consumed by herbivores.
- Abundance: Green plants are widely distributed and abundant in most ecosystems. They can be found in various habitats, including terrestrial and aquatic environments. Their abundance ensures a stable and continuous food supply for other organisms.
- Fixed in one place: Unlike animals, green plants are fixed in one place due to their root systems. This allows them to establish a stable base for the food chain, as they act as a foundation for the whole ecosystem.
Overall, green plants hold a crucial role in the food chain as they provide energy, are widely distributed, have the capacity to synthesize food, and form the primary link in the transfer of energy through the ecosystem.
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.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : CFCs deplete the ozone layer.
Reason : CFCs are used as refrigerants and in fire extinguishers.
- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : CFCs deplete the ozone layer.
Reason : CFCs are used as refrigerants and in fire extinguishers.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Kritika menon answered |
Understanding the Assertion and Reason
The assertion states that "CFCs deplete the ozone layer." This is indeed true. Chlorofluorocarbons (CFCs) are chemicals that have been widely used in various applications, particularly as refrigerants in air conditioning systems and in fire extinguishers. When released into the atmosphere, CFCs rise up and eventually reach the stratosphere, where they break down ozone molecules, leading to the depletion of the ozone layer.
Role of CFCs in Ozone Layer Depletion
- CFCs release chlorine atoms when they are exposed to ultraviolet (UV) radiation in the stratosphere.
- These chlorine atoms react with ozone (O3) molecules, resulting in the breakdown of ozone into oxygen (O2).
- The depletion of the ozone layer increases UV radiation reaching the Earth's surface, leading to harmful effects like skin cancer and cataracts.
Connection Between Assertion and Reason
The reason provided states that "CFCs are used as refrigerants and in fire extinguishers." This statement is also true as CFCs have historically been used in these applications. However, while the reason accurately describes the use of CFCs, it does not explain why they deplete the ozone layer. Therefore, while both statements are true, the reason does not provide a valid explanation for the assertion.
Conclusion
Given that both the assertion and the reason are true, but the reason does not correctly explain the assertion, the correct choice is:
- Option (b): Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
The assertion states that "CFCs deplete the ozone layer." This is indeed true. Chlorofluorocarbons (CFCs) are chemicals that have been widely used in various applications, particularly as refrigerants in air conditioning systems and in fire extinguishers. When released into the atmosphere, CFCs rise up and eventually reach the stratosphere, where they break down ozone molecules, leading to the depletion of the ozone layer.
Role of CFCs in Ozone Layer Depletion
- CFCs release chlorine atoms when they are exposed to ultraviolet (UV) radiation in the stratosphere.
- These chlorine atoms react with ozone (O3) molecules, resulting in the breakdown of ozone into oxygen (O2).
- The depletion of the ozone layer increases UV radiation reaching the Earth's surface, leading to harmful effects like skin cancer and cataracts.
Connection Between Assertion and Reason
The reason provided states that "CFCs are used as refrigerants and in fire extinguishers." This statement is also true as CFCs have historically been used in these applications. However, while the reason accurately describes the use of CFCs, it does not explain why they deplete the ozone layer. Therefore, while both statements are true, the reason does not provide a valid explanation for the assertion.
Conclusion
Given that both the assertion and the reason are true, but the reason does not correctly explain the assertion, the correct choice is:
- Option (b): Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : The concentration of harmful chemicals is more in human beings.Reason : Man is at the apex of the food chain.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : The concentration of harmful chemicals is more in human beings.
Reason : Man is at the apex of the food chain.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Avinash Patel answered |
Harmful chemicals accumulate progressively at each trophic level. Since man is at the apex of all the food chains, the concentration of harmful chemicals may be higher in human beings. The phenomenon involved is known as biomagnification.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Man is a herbivore.Reason : Omnivores eat both plant food and meat of animals.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'D'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Man is a herbivore.
Reason : Omnivores eat both plant food and meat of animals.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Anita Menon answered |
Man is an example of an omnivorous animal because Omni means all and vore means eater. An organism which can feed on the plant, as well as the meat of the animal, are called omnivorous.
Man consumes plants (fruit vegetables) and also eats the meat of animals like goat, chicken etc thus man is considered as the Omnivorous animal.
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
|
Lakshya Ias answered |
Autotrophs or producers occupy the first trophic level in a food chain, as they are the primary energy converters that transform sunlight into chemical energy, initiating the flow of energy through the ecosystem.
Which of the following is an autotroph?- a)Lion
- b)Insect
- c)Tree
- d)Mushroom
Correct answer is option 'C'. Can you explain this answer?
Which of the following is an autotroph?
a)
Lion
b)
Insect
c)
Tree
d)
Mushroom
|
Anju Mala answered |
Autotrophs means organisms who prepare their own food and heterotrophs are organisms who depend on autotrophs directly or indirectly and as you may be knowing that tree or plants prepare their own food by the process of photosynthesis , so c is the correct 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
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
|
Lohit Matani answered |
Autotrophs or producers, which include green plants capturing solar energy, form the first trophic level in a food chain. They convert sunlight into chemical energy, initiating the flow of energy through the ecosystem.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Tropical rain forests are disappearing fast from developing countries such as India.Reason : No value is attached to these forests because they are poor in biodiversity.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'C'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Tropical rain forests are disappearing fast from developing countries such as India.
Reason : No value is attached to these forests because they are poor in biodiversity.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Kiran Mehta answered |
Tropical rain forests have disappeared mainly due to man’s activities. Due to overpopulation in countries like India, rain forests are cut to make space available for man to live and build houses. To build buildings and factories man has incessantly cut down trees. This has caused the depletion of rainforests.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Trophic levels are formed by only plants.Reason : Food chains and webs are formed due to linked organisms on the basis of their nutrition.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'D'. Can you explain this answer?
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Trophic levels are formed by only plants.
Reason : Food chains and webs are formed due to linked organisms on the basis of their nutrition.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
e)
Both Assertion and Reason are false.
|
|
Anita Menon answered |
A trophic level is the position of an organism in a food chain. A food chain starts with producers which are green plants and occupy the lowest trophic level. The highest trophic level is occupied by carnivores which feed on lower trophic levels for energy. A simple food chain is represented as
Plant ---> Herbivore ---> Carnivore
Hence, trophic levels are formed by different organisms linked in a food chain.
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.
An ecosystem includes- a)all living organisms
- b)non-living objects
- c)both living organisms and non-living objects
- d)sometimes living organisms and sometimes non-living objects
Correct answer is option 'C'. Can you explain this answer?
An ecosystem includes
a)
all living organisms
b)
non-living objects
c)
both living organisms and non-living objects
d)
sometimes living organisms and sometimes non-living objects
|
Subhankar Kapoor answered |
An ecosystem is an interaction between the living organism (biotic component) and their physical environment (abiotic componenet). Thus, the correct answer is option C.
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.
Chapter doubts & questions for Our Environment - Science Class 10 2025 is part of Class 10 exam preparation. The chapters have been prepared according to the Class 10 exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for Class 10 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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