GSEB Solutions for Class 10 Science and Technology – Our Environment

GSEB Solutions for Class 10 Science and Technology – Our Environment (English Medium)

GSEB SolutionsMathsScience
Question 1:
Select the proper choice from the given multiple choices :

Question 1.1:
Which of the following is an example of biodegradable waste :
Solution :
A. Vegetables
Vegetable waste can be decomposed by biological processes. Thus, it is a biodegradable waste.

Question 1.2:
Which of the following is an example of non-biodegradable waste :
Solution :
D. Polythene
Polythene cannot be decomposed by biological processes. Thus, it is a non-biodegradable waste.

Question 1.3:
Ecosystem is an interacting system made up of :
Solution :
A. Organism and their physical surroundings
In an ecosystem, there is an interaction between all organisms including plants, animals, micro-organisms and their physical environment.

Question 1.4:
The structural and functional unit of the environment is known as :
Solution :
C. Ecosystem
In an ecosystem, there is an interaction between all living organisms and their physical environment. Thus, it is considered as the structural and the functional unit of the environment.

Question 1.5:
First order consumers are :
Solution :
B. Herbivores
Herbivores directly feed on producers and are thus, first order consumers.

Question 1.6:
Omnivorous organisms consume :
Solution :
C. Plants and animals both
Omnivorous organisms consume both plant and animals as food. They are called as tertiary consumers.

Question 1.7:
Edaphic factors are included in :
Solution :
A. Abiotic components
Edaphic factors are abiotic components which include soil structure and composition.

Question 1.8:
How many molecules of ozone can be decomposed by one atom of chlorine ?
Solution :
B. 1,00,000
Chlorine atom reacts with the ozone molecule and removes an atom of oxygen from the molecule one by one. One chlorine atom can decompose 1,00,000 molecules of ozone in this manner.

Question 1.9:
The most important compound which accounts for almost 80% of the total depletion of ozone layer is :
Solution :
C. Chlorofluoro carbon
Chlorine present in chlorofluorocarbon decomposes the molecules of ozone resulting in the depletion of the ozone layer.

Question 2:
Answer the following questions in brief :

Question 2.1:
What is an environment.
Solution :
Environment is an interacting medium of all plants, animals and human beings with their physical surroundings.

Question 2.2:
Define ecosystem.
Solution :
Ecosystem is an interacting system between all organisms and their physical environment.

Question 2.3:
Define food chain and food web.
Solution :
All living organisms which depend on each other for their requirement of food form a chain. This chain is called a food chain.
The interlinking of two or more food chains forms a net. This net is termed as a food web.

Question 2.4:
Give examples of solid waste.
Solution :
Solid waste includes:

• Fruits and vegetable waste such as peels
• Scales and bones from food remains
• Metal waste
• Glasses
• Plastic
• Polythene

Question 2.5:
What do you mean by biodegradable waste ?
Solution :
Waste which can be decomposed by biological processes and thus does not accumulate in the environment is called biodegradable waste.

Question 2.6:
Give examples of non-biodegradable waste.
Solution :
Non-biodegradable waste includes:

• Glass
• Plastic
• Polythene

Question 2.7:
How ozone is formed ?
Solution :
Oxygen molecules in the stratosphere absorb ultraviolet photons and undergo photodissociation i.e. an oxygen molecule splits into two oxygen atoms.
O₂→O + O
These free oxygen atoms then combine with oxygen molecules and in turn form ozone molecules.
O₂ + O → O₃

Question 2.8:
Name compounds responsible for depletion of ozone layer.
Solution :
Compounds responsible for depletion of ozone layer include:

• Chlorofluorocarbon
• Carbon Tetrachloride
• Methyl Chloroform
• Methyl Bromide

Question 3:
Write answers of the following questions :

Question 3.1:
Describe the types of waste.
Solution :
Waste can be classified as biodegradable waste and non-biodegradable waste.
Waste which can be decomposed by biological processes and thus does not accumulate in the environment is called biodegradable waste. Example – remains of fruits, vegetables, bones, scales etc.
Waste which cannot be decomposed by biological processes and thus accumulates in the environment is called non-biodegradable waste. Example – plastic, polythene, glass etc.

Question 3.2:
Explain the components of an ecosystem.
Solution :
An ecosystem comprises of two main components: biotic components and abiotic components.
Biotic components: All living organisms of an ecosystem make up biotic components. Example – producers, consumers and decomposers.
Abiotic components: All non-living factors of an ecosystem make up abiotic components. Example – soil, water, light, temperature, wind, humidity, rain, inorganic nutrients, dead organic matter etc.

Question 3.3:
Explain food chain giving suitable example.
Solution :
All living organisms which depend on each other for their requirement of food form a chain. This chain is called food chain.
The following is an example of food chain where the producers form the first trophic level, the herbivores, the second, and the carnivores, the third and the omnivores form the fourth trophic level.
Grasses ← Grasshopper ← Rats ← Hawks

Question 3.4:
Explain food web giving suitable example.
Solution :
The interlinking of two or more food chains forms a net. This net is termed as a food web.
An organism need not be confined to only one food chain. An individual organism may be linked to food chains of different ecosystems as well. This results in the formation of a food web.
Example – A snake can be a part of multiple food chains. It can feed on rats (terrestrial food chain) or on salamander (aquatic food chain) or even a sparrow (another terrestrial food chain), thus showing interlinking between different food chains and forming a food web.

Question 3.5:
What are the global problems ?
Solution :
Global problems are the problems which affect the entire planet and thus all living organisms on the planet. Some of the global problems are:

• Global warming
• Depletion of ozone layer
• Deforestation
• Loss of biodiversity and ecosystem
• Depletion of fisheries
• Water deficits
• Pollution
• Waste disposal

Question 3.6:
How amount of household waste can be reduced ?
Solution :
Following measures can help to reduce the amount of household waste:

• Buy loose fruits and vegetables instead of packed ones to avoid packaging.
• Use reusable nappies.
• Use rechargeable batteries.
• Buy and use reusable cloth, carry bags for shopping instead of paper bags or polythene bags.
• Donate old clothes, shoes and other waste household items instead of throwing them.
• Reuse the back side of used, waste paper as scrap paper.
• Always give paper for recycling instead of throwing them.
• Put kitchen and other biodegradable waste in a separate container and use it for making compost.

Question 4:
Answer the following questions in detail :

Question 4.1:
Explain Food Chain (with figure)
Solution :
All living organisms which depend on each other for their requirement of food form a chain. This chain is called a food chain.

The following is an example of food chain where the producers form the first trophic level, the herbivores, the second, the carnivores, the third and carnivores form the fourth trophic level.

Grasses ← Grasshopper ← Rats ← Hawks

A food chain describes the path in which energy and nutrients flow in an ecosystem. A food chain begins with producers which trap the energy from sunlight and produce food. This energy then moves in the form of food to herbivores or primary consumers followed by secondary, tertiary and quaternary consumers.

The flow of energy is always unidirectional in an ecosystem.

Question 4.2:
Explain Food web (with figure)
Solution :
The interlinking of two or more food chains forms a net. This net is termed as a food web.

An organism need not be confined to only one food chain. An individual organism may be linked to food chains of different ecosystems as well. This results in the formation of a food web.

Example – A snake can be a part of multiple food chains. It can feed on rats (terrestrial food chain) or salamander (aquatic food chain) or even a sparrow (another terrestrial food chain), thus showing interlinking between different food chains and forming a food web.