NCERT Solutions For Class 10 Science Chapter 13 Our Environment

Download Our Environment NCERT Solutions PDF

Students can download the solutions of the Our Environment chapter to improve their understanding of the ecosystem. The Class 10 Science Chapter 13 Our Environment question answer PDF can be accessed anytime and anywhere without the internet.

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Also Read,

• NCERT Exemplar Solutions for Class 10 Science Our Environment

• NCERT Notes for Class 10 Science Our Environment

Access Class 10 Science Chapter 13 Our Environment Solutions (In-text Exercise)

The chapter 'Our Environment' helps students learn about ecosystems, food chains, and how human actions affect nature. Given below are the Class 10 Science Chapter 13 Our Environment question answer, which are designed by subject experts following the NCERT curriculum for better understanding.

Topic 13.1: Ecosystem and its components:

Q1. What are trophic levels? Give an example of a food chain and state the different trophic levels in it.

Answer:

Every step or level of the food chain is referred to as a trophic level. Energy transfer in the form of food occurs from one trophic level to another. Trophic levels can be broadly divided into Producers, Primary, Secondary, and Tertiary Consumers.

An example of a food chain:

Grass → Grasshopper → Frog → Snake → Eagle

Here, Grass is a producer, Grasshopper is the herbivore, Frog is the first carnivore, Snake is the second carnivore, and Eagle at the top is the third carnivore.

Q2. What is the role of decomposers in the ecosystem?

Answer:

Decomposers decompose the dead and decaying organisms' organic matter into simpler inorganic compounds. Decomposition aids in recycling nutrients back into the ecosystem, thus providing a constant supply of energy. Through the decomposition of dead organisms, they clean the environment and avoid the buildup of waste. The inorganic compounds released also enrich the soil, making it fertile for plant growth. Decomposers thus have an important role in sustaining the ecosystem's balance.

They also help in decomposing plant litter, like leaves and twigs, which aids in soil creation. Without decomposers, dead organic material would pile up, throwing the cycle of life off balance. Bacteria and fungi are the major decomposers, functioning well to decompose complex materials.

Topic 13.2: How do Our Activities Affect the Environment?

Q1. Why are some substances biodegradable and some non-biodegradable?

Answer:

Substances that can be broken down by biological processes are said to be biodegradable. In our environment, many of the substances are broken down easily by decomposers. Examples: Paper, vegetable peels, etc.

However, substances that cannot be broken down biologically but only by physical means are known as non-biodegradable substances. Example: Plastic.

Q2. Give any two ways in which biodegradable substances would affect the environment.

Answer:

Two ways in which biodegradable substances would affect the environment are:

1. These substances, on degradation, can produce a foul smell that affects the population living nearby. They may also become a breeding place for insects.

2. Many harmful greenhouse gases may evolve during degradation, leading to global warming.

Q3. Give any two ways in which non-biodegradable substances would affect the environment.

Answer:

Any two ways in which non-biodegradable substances may affect the environment are:

1. The main problem caused is pollution. Non-biodegradable substances take many decades to degrade and hence remain in the environment, causing pollution.

2. They may render the soil infertile and hence affect the vegetation

Q4. What is ozone, and how does it affect any ecosystem?

Answer:

Ozone (O₃) is a molecule made of three oxygen atoms. It affects the ecosystem in two ways, depending on its location:

• In the upper atmosphere (stratosphere) - It forms a protective layer that absorbs harmful ultraviolet (UV) radiation. The depletion of this layer allows more UV rays to reach the Earth, harming living organisms.

• At ground level (troposphere) - It acts as a pollutant that harms the respiratory systems of humans and animals and damages plants and vegetation.

Q5. How can you help in reducing the problem of waste disposal? Give any two methods.

Answer:

Two methods used to reduce the problems of waste disposal are:

1. Throwing biodegradable and non-biodegradable waste into separate dustbins so that recycling can be done easily.

2. By putting the organic waste into compost pits dug in the ground, and preparing compost. This compost helps in increasing the fertility of the soil.

3. Practising the 3 R's: Reduce, Reuse, and Recycle.

Class 10 Science Chapter 13 Our Environment Solutions (Chapter-end Exercise)

Solving the questions is important, as it makes students more confident and also decreases their stress. So, in this, we will cover all Class 10 Science Chapter 13 Our Environment question answers.

Q1. Which of the following groups contains only biodegradable items?

(a) Grass, flowers, and leather

(b) Grass, wood, and plastic

(c) Fruit peels, cake, and lime juice

(d) Cake, wood, and grass

Answer:

Option (A)- Grass, flowers are biodegradable, but processed leather takes a very long time to decompose, so it is not fully biodegradable.

Option (B)- Grass, wood are natural and decompose easily, so they are biodegradable, but plastic is non-biodegradable.

Option (C)- Fruit peels, cake, and lime juice are all natural and easily decompose, so they are biodegradable.

Option (D)- Cake, wood, and grass are also natural materials that decompose easily and are biodegradable.

Hence, the correct option is (c) and (d).

Q2. Which of the following constitutes a food chain?

(a) Grass, wheat, and mango

(b) Grass, goat, and human

(c) Goat, cow, and elephant

(d) Grass, fish, and goat

Answer:

A food chain consists of different trophic levels.

(b) Grass → Goat → Human; constitute a food chain.

Here, the grass is a producer, the goat is the primary consumer, and the human is the secondary consumer.

Hence, the correct option is (b), Grass, goat, and human

Q3. Which of the following are environment-friendly practices?

(a) Carrying cloth bags to put purchases in while shopping

(b) Switching off unnecessary lights and fans

(c) Walking to school instead of getting your mother to drop you on her scooter

(d) All of the above

Answer:

All of the above-mentioned practices are environmentally friendly.

Hence, (d) All of the above is the correct answer.

Q4. What will happen if we kill all the organisms in one trophic level?

Answer:

If all the organisms of a trophic level are destroyed, the food chain will become unbalanced. The animals in the direct higher trophic level will die because of a lack of food, and the effect will follow. Also, the number of organisms in the direct lower trophic level will continue to grow, and this will destroy its direct lower level because of greater demand but lesser supply. So the entire food chain will collapse.

Q5. Will the impact of removing all the organisms in a trophic level be different for different trophic levels? Can the organisms of any trophic level be removed without causing any damage to the ecosystem?

Answer:

Yes, the impact of removing all the organisms in a trophic level will be different for different trophic levels.

No, the organisms of any trophic level cannot be removed without causing any damage to the ecosystem.

Consider the following example:

Grass → Deer → Lion

1. If all the grass is removed, the deer will die out due to starvation, which in turn will wipe out the lions.

2. If the entire deer population is removed, the lions will die out due to starvation. The grasses will increase in number and turn the land into forests.

3. If all the lions are removed, the population of deer will keep on increasing, which in turn will eat all the grass, leaving the land barren.

Q6. What is biological magnification? Will the levels of this magnification be different at different levels of the ecosystem?

Answer:

Biological Magnification is the rise in the concentration of toxic materials in the body of the organism at every trophic level.

Yes, the magnification levels are varied at various levels of the ecosystem. It is at the highest level of the food chain.

Since chemicals such as pesticides and DDT are not degradable, these collected progressively at every trophic level. Since human beings are at the top of any food chain, the highest concentration of these chemicals is collected in their bodies.

Q7. What are the problems caused by the non-biodegradable wastes that we generate?

Answer:

The non-biodegradable waste that we generate has the following problems for the environment:

1. Non-biodegradable wastes like pesticides reduce the fertility of soil as they penetrate it. The pH level of the soil becomes unsuitable for vegetation.

2. Non-biodegradable wastes like pesticides accumulate progressively at each trophic level and thus harm the organisms.

3. Non-biodegradable materials like plastics, when burning, release toxic chemicals into the environment, which leads to air pollution.

Q8. If all the waste we generate is biodegradable, will this have no impact on the environment?

Answer:

If everything we throw away is biodegradable, it can still affect the environment if not dumped properly. It can cause a bad odour, impacting surrounding communities. It can also be a breeding ground for mosquitoes and other insects, which may lead to increased disease transmission. Proper dumping grounds must thus be established for effective waste management.

Composting is the best method of disposing of biodegradable waste, as it transforms waste into organic matter that can be utilized. Proper segregation of waste should be ensured by municipal authorities to allow recycling and composting. Public awareness campaigns can inform people about proper waste disposal. A well-maintained and clean environment leads to healthier and sustainable living.

Q9. Why is damage to the ozone layer a cause for concern? What steps are being taken to limit this damage?

Answer:

The ozone layer in the stratosphere is responsible for absorbing dangerous UV rays, which protects all living organisms. If the ozone layer gets depleted, higher exposure to UV radiation can cause severe health problems, such as skin cancer in human beings, and harm plants and animals. Thus, ozone layer damage is a significant environmental issue.

To minimize this harm, the manufacture of chlorofluorocarbons (CFCs), the cause of ozone depletion, was phased out in 1986. Global agreements such as the Montreal Protocol have been enforced to control ozone-depleting substances. Public awareness programs promote the use of environmentally friendly products. Researchers are also working on sustainable substitutes for toxic chemicals to save the ozone layer.

Approach to Solve Our Environment Class 10 Question Answer

To answer Our Environment questions, students should simply follow the steps given below:

1. Start by understanding that an ecosystem is made up of biotic (living) and abiotic (non-living) elements.

2. Biotic elements are living things such as producers (plants), consumers (animals), and decomposers (bacteria, fungi).

3. Abiotic elements are non-living elements such as sunlight, water, air, soil, temperature, and minerals.

4. Learn how biotic and abiotic elements interact to create balance in the ecosystem and sustain life. Students can take help from the Class 10 Science Chapter 13 Our Environment Solutions.

5. Study how producers use abiotic factors (sunlight, water) to produce food, and then move to the consumers and decomposers.

6. Mark important terms: ecosystem, biotic, abiotic, producers, consumers, decomposers, and nutrient cycle. Students have to practice the NCERT Solutions for Class 10 Science to score well in exams.

Also, check the NCERT Books and NCERT Syllabus here:

• NCERT Books Class 10 Science

• NCERT Syllabus Class 10 Science

• NCERT Books Class 10

• NCERT Syllabus Class 10

Important Topics of Class 10 Science Chapter 13 Our Environment

This is the list of the topics that students are going to study in the chapter Our Environment. Questions are asked frequently about these topics. So, students are advised to gain clarity using the NCERT Solutions for Class 10 Science Chapter 13 Our Environment.

• Ecosystems and Their Components

• Food Chains and Food Webs

• Trophic Levels and Energy Flow

• Biodegradable and Non-Biodegradable Wastes

• Effect of Human Activities on the Environment

Important Question from Class 10 Science Chapter 13 Our Environment

This chapter explains how different components of the environment interact and how human activities impact the ecosystem. Practicing different questions given in the NCERT Solutions for Class 10 Science Chapter 13 Our Environment improves confidence.

Question: Which of the following is a non-biodegradable waste?

a) Vegetable peels

b) Paper

c) Plastic

d) Cotton

Answer: The correct answer is option c) Plastic

Explanation: Paper, clipboards, metal containers like aluminium plants and human waste, and several plant products are classified under biodegradable substances. However, an example of a non-biodegradable substance could be plastic products.

What Students Learn from Our Environment NCERT Solutions

This chapter helps students understand the link between living beings and their surroundings. A few important things that students learn from these solutions are given below:

• The Our Environment NCERT Solutions explain food chains and food webs in simple terms.
• Students learn about the importance of energy flow in ecosystems.
• It highlights how waste management and recycling can reduce pollution.
• Students get clarity on ozone layer depletion and its harmful effects.
• The Our Environment class 10 question answer makes students aware of sustainable practices to protect the planet.

NCERT Chapter-wise Solutions for Class 10 Science

Below are the chapter-wise solutions: