Important Questions of Our Environment Class 10 Science Chapter 15
Question 1.
Why is the maximum concentration of pesticides found in human beings?
Year of Question :(2012)
Answer:
The pesticides are not biodegradable, they get accumulated progressively at each trophic level. As human beings occupy the topmost level in food chain, their concentration becomes maximum in our bodies
Question 2.
Give one method which could be applied to reduce our intake of pesticides through food to some extent?
Year of Question :(2015)
Answer:
By using biological methods for controlling insects in fields and by washing fruits and vegetables before eating could help to reduce our intake of pesticides through food to some extent
Question 3.
Various steps in a food chain represent?
Year of Question :(2015)
- (a) food web
- (b) trophic level
- (c) ecosystem
- (d) biomagnification
Answer:
Question 4.
With regard to various food chains operating in an ecosystem, man is a?
Year of Question :(2015)
- (a) Consumer
- (b) Producer
- (c) Producer and consumer
- (d) Producer and decomposer. (2020)
Answer:
Question 5.
Food web is constituted by?
Year of Question :(2015)
- (a) relationship between the organisms and the environment
- (b) relationship between plants and animals
- (c) various interlinked food chains in an ecosystem
- (d) relationship between animals and environment. (2020)
Answer:
- (c) various interlinked food chains in an ecosystem
Question 6.
What is an ecosystem?
Year of Question :(2017)
Answer:
An ecosystem is defined as a structural and functional unit of the biosphere. It comprises of living organisms and their non-living environment that interact by means of food chains and biogeo-chemical cycles resulting in energy-flow, biotic diversity and material cycling to form stable self-supporting system
Question 7.
Why is a lake considered to be a natural ecosystem?
Year of Question :(2017)
Answer:
Lake is an ecosystem where living organisms grow, reproduce and interact among each other as well as with abiotic components and carry out other activities in nature by themselves without any human interference, therefore it is referred to as a natural ecosystem
Question 8.
In the following food chain, plants provide 500 J of energy to rats. How much energy will be available to hawks from snakes?
Plants ? Rats ? Snakes ? Hawks ?
Year of Question :(2017)
Answer:
In an ecosystem, only 10% of energy is transferred from one trophic level to next, i.e. 10 percent law and rest is dissipated into the environment. Therefore, if plants (being producers-1st trophic level)-transfer 500 J of energy to rats (2nd trophic level) then rats would transfer 50 J of energy to snakes (3rd trophic level) which in turn will transfer only 5 J of energy to hawks (4th or last trophic level) in a food chain
Question 9.
In the following food chain, 100 J of energy is available to the lion. How much energy was available to the producers?
Plants ? Deer ? Lion ?
Year of Question :(2017)
Answer:
As per 10% law of flow of energy in an ecosystem only 10% of energy is received by the next trophic level. Hence, in the given food chain : If 100 .J of energy is available to lion, the plants or producers have 10,000 J of energy available to them
Question 10.
List two biotic components of a biosphere?
Year of Question :(2015)
Answer:
Two biotic components of a biosphere are
- (i) Producers - Include organisms which can produce their food using simple inorganic compounds, e.g., all green plants, blue green algae (cyanobacteria)
- (ii) Consumers - Include organisms which are unable to synthesise their food, therefore, utilise materials and energy stored by the producers or eat other organisms, e.g., all the animals
Question 11.
Why are green plants called producers?
Year of Question :(2016)
Answer:
Green plants are called producers because they manufacture their own food with the help of CO2 and H2O in the presence of sunlight and chlorophyll
Question 12.
In a food chain of frog, grass, insect and snake, assign trophic level to frog?
Year of Question :(2016)
Answer:
In the given food chain, frog belongs to the third trophic level as shown here
Question 13.
Why do producers always occupy the first trophic level in every food chain?
Year of Question :(2016)
Answer:
Producers are the green plants that can manufacture food using CO2 and H2O in the presence of sunlight, i.e., they are autotrophs. They serve as a source of food for all non-producers or consumers directly or indirectly. Hence, producers occupy the first trophic level in a food chain
Question 14.
We often use the word environment. What does it mean?
Year of Question :(2016)
Answer:
Environment can be defined as the physical or biological world where an organism lives. Literally speaking, an organisms immediate surrounding constitutes its environment which includes both biotic and abiotic components around him
Question 15.
Which of the following are always at the second trophic level of food chains? Carnivores, Autotrophs, Herbivores?
Year of Question :(2015)
Answer:
Herbivores always occupy the second trophic level of food chains
Question 16.
The following organisms form a food chain. Which of these will have the highest concentration of non-biodegradable chemicals? Name the phenomenon associated with it. Insects, Hawk, Grass, Snake, Frog?
Year of Question :(2015)
Answer:
Among the following organisms of the food chain, hawk being top consumer is present at topmost trophic level, hence will have the highest concentration of non-biodegradable chemicals due to a phenomenon known as biomagnification
Question 17.
List two examples of natural ecosystem?
Year of Question :(2012)
Answer:
The two examples of natural ecosystem are
- Forest ecosystem
- River ecosystem
Question 18.
What is meant by the term Biomass?
Year of Question :(2014)
Answer:
Biomass is the total amount of living or organic matter in an ecosystem at any time
Question 19.
Bacteria and fungi are called decomposers. Why?
Year of Question :(2012)
Answer:
Bacteria and fungi are called decomposers because these microorganisms break down the complex organic matter present in dead plants and animals into simpler substances
Question 20.
In a food chain, if 10,000 joules of energy is available to the producer, how much energy will be available to the secondary consumer to transfer it to the tertiary consumer?
Year of Question :(2012)
Answer:
According to ten percent law, 10% of the energy of producer will be available to primary consumer, and 10% of this energy will be available to secondary consumer and so on.
Hence, 100 J of energy will be available to the secondary consumer to transfer it to tertiary consumer
Question 21.
Consider the following food chain which occurs in a forest:
Grass ? Deer ? Lion
If 10000 J of solar energy is available to the grass, how much energy would be available to the deer to transfer it to the lion?
Year of Question :(2015)
Answer:
The energy available to the deer is 1000 J to transfer it to the lion. This can be depicted as follows:
Question 22.
What is meant by biological magnification?
Year of Question :(2011)
Answer:
Biological magnification or biomagnification refers to the process of accumulation of non- biodegradable chemicals (pesticides, etc.) into the body of organisms through the food chain which go on increasing in its concentration at each trophic level
Question 23.
Give an example to illustrate that indiscriminate use of pesticides may result in the degradation of the environment?
Year of Question :(2011)
Answer:
Pesticides are the chemicals used to kill plant and animal pests. They are non-biodegradable and toxicants. For example, excessive use of DDT resulted in reduced population of fish eating birds. DDT accumulated in such birds through the food chain. It interfered with the egg shell formation. The shell being thin broke due to weight of the bird during incubation. Hence, their population declined
Question 24.
What are decomposers? List two important roles they play in the environment?
Year of Question :(2012)
Answer:
Decomposers are microorganisms including bacteria and fungi which decompose or break-down the complex organic compound present in dead plants and animals into simpler substances. Role of decomposers in environment are
- They help in decomposing dead bodies of plants and animals and hence act as cleansing agents of environmcnl
- They help in recycling of materials in the ecosystem lo maintain its stability
Question 25.
List two reasons to show that the existence of decomposers is essential in an ecosystem?
Year of Question :(2014)
Answer:
The existence of decomposers in an ecosystem is essential because
- (i) If there were no decomposers, then the dead bodies of plants and animals would keep lying as such and the elements constituting plant and animal bodies would never be returned to their original pools like soil, air and water. In such case the organic waste go on accumulating and the cyclic process of life and death would be disrupted
- (ii) Decomposers make the soil fertile by providing/replenishing nutrients to it, thus forming the integral part of ecosystem
Question 26.
State with reason any two possible consequences of elimination of decomposers from the earth?
Year of Question :(2014)
Answer:
Consequences of elimination of decomposers are
- (i) There would be no recycling of nutrients and therefore, raw materials to produce food will not be available to producers. Hence, the food chains will get affected
- (ii) The dead bodies of plants and animals will go on accumulating in the absence of decomposition thereby polluting the environment
Question 27.
What does a trophic level represent in a food chain? State the position of autotrophs and herbivores in a food chain?
Year of Question :(2014)
Answer:
Trophic level represents each of several hierarchical levels of a food chain operating in an ecosystem, consisting of organism sharing the same function in the food chain and the same nutritional relationship to the primary sources of energy.
The position of producers (or autotrophs) in a food chain constitute the first trophic level. They fix up suns energy and make it available for consumers. The herbivores or primary consumers (which feed upon plants) constitute the second trophic level in a food chain
Question 28.
- (a) From the following group of organisms create a food chain which is most advantageous for human beings in terms of energy.
Hawk, Rat, Cereal plant, Goat, Snake, Human being
- (b) State the possible disadvantage if the cereal plant is growing in soil rich in pesticides
- (c) Construct a food web using the organisms mentioned above. (2020)
Answer:
- (a) A food chain which is most advantageous for human beings in terms of energy is:
Cereal plant ? Human being
- (b) If the cereal plant is growing in soil rich in pesticides, these pesticides are absorbed by growing plants along with water and minerals, when animals eat these cereal plants, these poisonous chemical pesticides go into their bodies through food. This increase in concentration of harmful pesticides in the body of living organisms at each trophic level of a food chain is called biological magnification. Pesticides are lethal to non-target species also. The extensive use of pesticides in agriculture can change the community of microorganisms living in soil
Question 29.
- (a) Create a food chain of the following organisms.
Insect, Hawk, Grass, Snake, Frog
- (b) Name the organism at the third trophic level of the created food chain
- (c) Which organism of this food chain will have the highest concentration of non- biodegradable chemicals
- (d) Name the phenomenon associated with it
- (e) If 10,000 Joules of energy is available to frogs, how much energy will be available to snakes in this food chain? (2020)
Answer:
- (a) Grass ? Insect ? Frog ? Snake ? Hawk
- (b) Frog is present in the above created food chain
- (c) Hawk is the top consumer of the food chain, so, it will have high concentration of non- biodegradable chemicals
- (d) Biological magnification
- (e) As per 10% law of flow of energy in an ecosystem, only 10% of energy is received by the next trophic level. Hence, in the given food chain, if 10,000 Joules of energy is available to frog, then the energy available to snakes will be 1000 Joule
Question 30.
- (a) What is an ecosystem
- (b) List any two natural ecosystems
- (c) We do not clean ponds or lakes but an aquarium needs to be cleaned regularly. Why? (2020)
Answer:
- (a) An ecosystem is defined as a structural and functional unit of the biosphere comprising of living organisms and their non-living environment
- (b) Two examples of natural ecosystem are: pond ecosystem and grassland ecosystem
- (c) Ponds or lakes being natural ecosystems are self sufficient and do not need to be maintained regularly. On the other hand, aquarium being an artificial ecosystem needs to be cleaned and maintained regularly as it contains mainly fishes as living organisms, as compared to natural ecosystems where presence of other organisms maintains a balance. Also, because the producers and decomposers are absent in aquarium the fish waste or excretory products, i.e., ammonia may turn into toxic compounds and accumulate to dangerous levels causing the fishes to die. Hence, the artificial ecosystems like aquarium needs to be cleaned regularly
Question 31.
What is meant by trophic level in a food chain? Construct a terrestrial food chain with trophic levels. The energy flow in a food chain is always unidirectional. Why?
Year of Question :(2020)
Answer:
The various steps representing organisms in a food chain at which the transfer of food and energy takes place are called trophic levels.
Four trophic levels in a terrestrial food chain:
Grass ? Rabbit ? Wild cat ? Tiger
There is a unidirectional llow of energy from sun to producers and subsequenllv to series of different types of consumers, i.e.,
Solar radiations ? Producers ? Herbivores ? Carnivores
It cannot pass in reverse direction, lhcre is always a decrease in the flow of energy and content with rise in trophic level. Large quantity of energy is lost at each step in the form of heat and is also used up in various metabolic activities.
Question 32.
Complete the following flow chart based on ecosystem and its components?
Year of Question :(2012)
Answer:
- Aquatic
- Abiotic
- Inorganic substances
- Producers
- Structural and functional unit of biosphere
Question 33.
- (a) Construct a terrestrial food chain comprising four trophic levels
- (b) What will happen if we kill all organisms in one trophic level
- (c) Calculate the amount of energy available to the organisms at the fourth trophic level. If the energy available to the organisms at the second trophic level is 2000 J. (2020)
Answer:
- (a) A terrestrial food chain with four trophic levels is :
Grass ? Insect ? Frog ? Eagle
- (b) Removal of the organisms of any trophic level will always adversely affect the ecosystem, e.g., the removal of lions and tigers (top carnivores) will cause rapid increase in deer population, which leads to rapid consumption of vegetation resulting in scarcity of vegetation and population crash of deer
- (c) According to ten percent law, only 10% of the energy is received by the next trophic level.
If the energy available at second trophic level (T2) is 2000 J, so the 20 J of energy will be at fourth trophic level (T4)
Question 34.
Define an ecosystem. Draw a block diagram to show the flow of energy in an ecosystem?
Year of Question :(2019)
Answer:An ecosyslcm is defined as a structural and functional unil of ihe biosphere. It comprises of living organisms and their non-living environment that interact by means of food chains and biogeo-chemical cycles resulting in energy-flow, biotic diversity and material cycling to form stable self-supporting system.
Green plants capture about 1% of the solar energy incident on the earth to carry out the process of photosynthesis. A part of this trapped energy is used by plants in performing their metabolic activities and some energy is released as heat into the atmosphere. The remaining energy is chemical energy stored in the plants as photosynthetic products. When these green plants are eaten up by herbivores, the chemical energy stored in the plants is transferred to these animals. These animals (herbivores) utilise some of this energy for metabolic activities and some energy is released as heat while the remaining energy is stored in their body. This process of energy transfer is repeated till top carnivores. In an ecosystem, transfer of energy follows 10 percent law, i.e,, only 10 percent of the energy is transferred to each trophic level from the lower trophic level. Nearly 90 percent of energy is lost when it moves from one trophic level to the next.
The given block diagram shows unidirectional flow of energy at different trophic levels in a freshwater ecosystem:
Question 35.
What is a food chain? Why is the flow of energy in an ecosystem unidirectional? Explain briefly?
Year of Question :(2019)
Answer:
The sequential interlinking of organisms involving transfer of food energy from the producers, through a series of organisms with repeated eating and being eaten is called the food chain. A food chain involves a nutritive interaction between the living organisms of an ecosystem. There is a unidirectional flow of energy from sun to producers and subsequently to series of different types of consumers, i.e.,
Solar radiations ? Producers ? Herbivores ? Carnivores
It cannot pass in reverse direction. There is always a decrease in the flow of energy and content with rise in trophic level. Large quantity of energy is lost at each step in the form of heat and is also used up in various metabolic activities
Question 36.
"Energy flow in food chains is always unidirectional." Justify this statement.
Explain how the pesticides enter a food chain and subsequently get into our body?
Year of Question :(2014)
Answer:
Some harmful non-biodegradable chemicals (pesticides, e.g., D.D.T.) enter the bodies
of organisms through the food chains and get concentrated at each trophic level. This phenomenon is called biomagnification or biological magnification. For example, in a food chain operating in a pond, river or lake, the water contains a small amount - 0.02 ppb (parts per billion) of harmful pesticides, i.e., D.D.T. When this water is consumed by phytoplanktons and zooplanktons, the concentration of these chemicals increases to 5 ppm. Fishes feeding on these, accumulate 240 ppm. Birds and humans feeding on these fishes were found to contain 1600 ppm of these chemicals. Thus, there is an increase in the concentration of the chemicals at each trophic level
Question 37.
"Our food grains such as wheat and rice, the vegetables and fruits and even meat are found to contain varying amounts of pesticide residues." State the reason to explain how and why it happens. ?
Year of Question :(2014)
Answer:
Pesticides are poisonous chemical substances which are sprayed over crop plants to protect them from pests and diseases. These chemical pesticides mix up with soil and water. From soil and water, these pesticides are absorbed by the growing plants along with water and other minerals. When herbivorous animals feed on these plants the poisonous pesticides enter their bodies through the food chain. Similarly, when the carnivorous animals eat these herbivores, the pesticides get transferred to their bodies. Therefore, the plant products such as food grains, vegetables and fruits as well as meat of animals contain varying amounts of pesticide residues in them depending upon the trophic level they occupy in a food chain
Question 38.
What is meant by food chain? "The number of trophic levels in a food chain is limited." Give reason to justify this statement. ?
Year of Question :(2014)
Answer:
The sequence of living organisms in a community in which one organism consumes or feeds upon another organism to transfer food energy, is called a food chain. The various steps in a food chain at which the transfer of food (or energy) takes place are called trophic levels. In fact, in a food chain, each step representing an organism forms a trophic level.
The number of trophic levels in a food chain are limited because at each trophic level only 10% of energy is utilised for the maintenance of organism which occur at that trophic level and the remaining large portion is lost as heat. As a result organisms at each trophic level pass on lesser energy to the next trophic level, than they receive. The longer the food chain, the lesser is the energy available to the final member of food chain. Food chains generally consist of three or four trophic levels because beyond that the energy available to the next organism will be too small and insufficient to sustain the life of that organism
Question 39.
- (a) What is an ecosystem? List its two main components
- (b) We do not clean ponds or lakes, but an aquarium needs to be cleaned regularly. Explain. (Delhi 2013)
Answer:
The two main components of ecosystem are
- Abiotic components - Non-living components of ecosystem, e.g., soil, water, air, light, etc
- Biotic components - Living components of ecosystem, e.g., plants, animals and microbes
Question 40.
Choose the incorrect statement from the following?
Year of Question :(2015)
- (a) Ozone is a molecule formed by three atoms of oxygen.
- (b) Ozone shields the surface of the earth from ultraviolet radiations.
- (c) Ozone is deadly poisonous.
- (d) Ozone gets decomposed by UV radiations. (2020)
Answer:
- (d) Ozone gets decomposed by UV radiations. (2020)
- Answer questions numbers 41 to 44 on the basis of your understanding of the following paragraph and the related studied concepts:
India today is facing the problem of overuse of resources, contamination of water and soil and lack of methods of processing the waste. The time has come for the world to say goodbye to "single use plastics". Steps must be undertaken to develop environment-friendly substitutes, effective plastics waste collection and methods of its disposal. Indore treated 15 lakhs metric tonnes of waste in just 3 years, through biomining and bioremediation techniques. Bioremediation involves introducing microbes into a landfill to naturally break it down and biomining involves using trommel machines to sift through the waste to separate to soil and the waste component. The city managed to chip away 15 lakh metric tonnes of waste at a cost of around t 10 crore. A similar experiment was successfully carried out in Ahmedabad also
Question 41.
State two methods of effective plastic waste collection in your school?
Year of Question :(2012)
Answer:
Two methods of effective plastic waste collection : (i) Use of separate dustbins for plastic collection (ii) Use of reusable for the canteen and school events (iii) Encourage less plastic in packed lunches
Question 42.
Name any two uses of single use plastic in daily life?
Year of Question :(2012)
Answer:
Single use plastic, often also referred to as disposable plastics are commonly used for plastic packaging and include items intended to be use only once before they are thrown away or recycled. These include grocery bags, food packaging, bottles, straws, containers, cups and cutlery
Question 43.
If we discontinue the use of plastic, how can an environment-friendly substitute be provided?
Year of Question :(2012)
Answer:
Best alternativescan be use of stainless steel, glass and platinum. Silicone storage containers. Cloth bags can be used in place of plastic bags. Use of wooden cleaning brushes, kitchen utensils and cutting board, pottery and other ceramics products, etc
Question 44.
Do you think microbes will work similarly in landfill sites as they work in the laboratory? Justify your answer?
Year of Question :(2020)
Answer:
Microbes may not work exactly the same way in landfill sites as they work in laboratories because it is difficult to replicate the exact ambient conditions required for the microbes to thrive in these two conditions. But due to same downstream processing and other mechanism, they will work similarly in landfill sites
Question 45.
The depletion of ozone layer is a cause of concern. Why?
Year of Question :(2016)
Answer:
Ozone layer is the ozone rich area in the stratospheric layer of atmosphere which acts as a protective shield by preventing harmful UV radiations from entering the Earth surface. Hence, the depletion of ozone layer is a cause of concern
Question 46.
Write one negative effect on the environment, of affluent life style of few persons of a society?
Year of Question :(2014)
Answer:
Affluent lifestyle of few persons leads to exploitation and over consumption of resources leading to their scarcity and generation of greater amount of waste materials which causes imbalance in environment
Question 47.
Why is excessive use of CFCs a cause of concern?
Year of Question :(2016)
Answer:
CFCs or Chlorofluorocarbons are potent compounds that release active chlorine in the atmosphere which reacts with ozone molecules present there to convert them to oxygen. This results in thinning of ozone layer. Hence, excessive use of CFCs is a cause of concern
Question 48.
What is the function of ozone in the upper atmosphere?
Year of Question :(2013)
Answer:
Ozone (O3) gas forms a protective shield in the upper atmosphere that absorbs most of the harmful ultraviolet radiations coming from Sun that can harm human beings, animals and plants. It protects us from various health hazards
Question 49.
Why should biodegradable and non- biodegradable wastes be discarded in two separate dustbins?
Year of Question :(2013)
Answer:
Biodegradable wastes are decomposed naturally by the action of microbes which degrade them to their simple constituents enabling their nutrients to recycle among the biotic and abiotic components of ecosystem. However, non-biodegradable wastes cannot be disposed off naturally since they cannot be decomposed by microbes. Such wastes are either recycled, incinerated or put in landfills, etc. As the disposal methods of the two types of waste is different, it is advisable to discard the two types of waste in two separate dustbins
Question 50.
Write the full name of the group of compounds mainly responsible for the depletion of ozone layer?
Year of Question :(2013)
Answer:
Chlorofluorocarbons (CFCs) are the group of compounds mainly responsible for ozone depletion
Important Questions and Answers from Chapter 15: Our Environment
Question 1.
What is an ecosystem? What are its components?
Answer:
An ecosystem is a system where living organisms interact with each other and with non-living components.
Components of an Ecosystem:
Biotic Components (Living): Plants, animals, microorganisms.
Abiotic Components (Non-living): Air, water, sunlight, soil, temperature.
Question 2.
What are food chains and food webs? Give an example of each.
Answer:
Food Chain:
A food chain shows how energy moves from one organism to another in a sequence.
Example: Grass → Deer → Lion.
Food Web:
A food web is a collection of interconnected food chains.
Example: In a pond ecosystem, Algae ? Fish ? Bird can be part of a food web.
Question 3.
Explain trophic levels. Name the four trophic levels with examples.
Answer:
Trophic levels are the positions that organisms occupy in a food chain.
First Trophic Level (Producers):
Organisms like green plants that make food from sunlight.
Example: Grass.
Second Trophic Level (Primary Consumers):
Herbivores that eat plants.
Example: Deer.
Third Trophic Level (Secondary Consumers):
Carnivores that eat herbivores.
Example: Frog.
Fourth Trophic Level (Tertiary Consumers):
Larger carnivores that eat smaller carnivores.
Example: Lion.
Question 4.
What is biological magnification? How does it affect humans?
Answer:
Biological magnification is the process where harmful chemicals accumulate and increase in concentration at each trophic level of the food chain.
Effects on Humans:
Humans, being at the top of the food chain, accumulate the highest amount of these chemicals.
This can lead to health problems like cancer or nervous system disorders.
Examples of harmful chemicals include pesticides and mercury.
Question 5.
How does energy flow in an ecosystem? Why is it unidirectional?
Answer:
Energy Flow in an Ecosystem:
Energy enters the ecosystem through producers (plants) that convert sunlight into food.
This energy moves to primary consumers, then to secondary consumers, and so on.
Unidirectional Energy Flow:
Energy flow is unidirectional because once energy is transferred, it cannot return to the previous trophic level.
A large amount of energy is lost as heat at each level, making it unavailable for further use.
Question 6.
What is the role of decomposers in an ecosystem? Why are they important?
Answer:
Decomposers are organisms like bacteria and fungi that break down dead plants and animals into simpler substances.
Importance of Decomposers:
They help in recycling nutrients back into the soil.
Without decomposers, dead matter and waste would accumulate, disrupting the ecosystem.
Question 7.
What are biodegradable and non-biodegradable substances? Give examples of each.
Answer:
Biodegradable Substances:
These substances can be broken down by microorganisms.
Examples: Vegetable peels, paper, fruit waste.
Non-biodegradable Substances:
These cannot be broken down easily and remain in the environment for a long time.
Examples: Plastic, glass, metals.
Question 8.
What is the ozone layer? How is it being depleted?
Answer:
The ozone layer is a protective layer in the Earth’s atmosphere that blocks harmful UV radiation from the Sun.
Ozone Depletion:
The use of chemicals like CFCs (Chlorofluorocarbons) in refrigerants and aerosol sprays has damaged the ozone layer.
The Montreal Protocol (1987) was an international agreement to reduce CFC production.
Question 9.
How does the depletion of the ozone layer affect living organisms?
Answer:
Effects of Ozone Layer Depletion:
Increased exposure to UV rays, which can cause skin cancer, eye damage, and weakened immune systems.
UV radiation also affects plant growth and harms aquatic ecosystems.
Question 10.
What are some ways to manage waste effectively?
Answer:
Ways to Manage Waste:
Segregation: Separate biodegradable and non-biodegradable waste.
Recycling: Reuse materials like plastic, paper, and metal.
Composting: Convert organic waste like food scraps into fertilizer for plants.
Reduce: Minimize the use of disposable items and packaging.
Awareness: Educate people about the importance of waste reduction.