NCERT Solutions Class 9 Science Chapter 14 Natural Resources
NCERT Solutions Class 9 Science Chapter 14 Natural Resources: National Council of Educational Research and Training Class 9 Science Chapter 14 Solutions – Natural Resources. NCERT Solutions Class 9 Science Chapter 14 PDF Download.
NCERT Solutions Class 9 Science Chapter 14: Overview
Board |
NCERT |
Class |
9 |
Subject |
Science |
Chapter |
14 |
Chapter Name |
Natural Resources |
Topic |
Exercise Solutions |
NCERT Solutions Class 9 Science Chapter 14 – Natural Resources
- Intext questions
1.) How is our atmosphere different from the atmospheres on Venus and Mars?
Ans: The earth’s atmosphere comprises of a mixture of gases like Nitrogen, Oxygen, carbon dioxide and water vapor. All these gases are responsible for life on the planet earth. On the other hand, there are planets like Venus and Mars whose atmosphere is composed of more than 95% carbon dioxide.Due to this reason life does not exist on these planets.
2.) How does the atmosphere act as a blanket?
Ans: Air is a bad conductor of heat, which plays an important role in controlling the environmental temperature. The average temperature is maintained throughout the day. Apart from this the ozone layer protects us from the other harmful radiations from the sun.
3.) What causes winds?
Ans: Winds are generated as the surface of the earth gets heated unevenly. Due to this there is a difference in air pressure which is created. This leads to formation of wind.
4.) How are clouds formed?
Ans: Water from sea, rivers, lakes etc. gets heated during the day time and is converted into water vapor. This vapor rises up along with air. At a certain height this vapor cools down and forms small droplets which condense on dust particles around a central nucleus and leads to formation of clouds.
5.) List any three human activities that you think would lead to air pollution.
Ans:1.) The burning of fossil fuels like coal and petroleum is a major cause of air pollution.
2) Fumes in form of shoot or carbon particles released from industries and mines also contribute to pollution.
3) vehicles smoke is a major contribute to air pollution.
6.) Why do organisms need water?
Ans: Water is the most important fluid.it is a universal solvent. Water is a part of all the metabolic and cellular process of the body. It is an essential component of plants photosynthesis. All the reaction which takes place in an organism require a water medium. It is also a transport fluid which carries dissolved substances in the body.
7.) What is the major source of fresh water in the city/town/village where you live?
Ans: The major source of fresh water in my city is rainfall, the river, wells around the city etc.
8.) Do you know of any activity which may be polluting this water source?
Ans: A number of human activities can pollute water such as
- Bathing or washing cloths and utensils in the nearby waterbodies.
- Dumping the wastes generated in industries directly in river bodies.
- Fertilizers and pesticides used in agriculture industry contribute to water pollution.
9.) What are the different states in which water is found during the water cycle?
Ans: Water is found in solid, liquid and gaseous state in the water cycle. In the water cycle snow or ice forms the solid state of water. The water in water bodies like the sea, rivers, ponds make up the liquid state of water. The water vapors is gaseous state of water.
10.) Name two biologically important compounds that contain both oxygen and nitrogen
Ans: The two essential biologically important compounds that contain both oxygen and nitrogen are proteins, vitamins and the nucleic acids like DNA (Deoxyribonucleic Acid), RNA (Ribonucleic Acid).
11.) List any three human activities which would lead to an increase in the carbon dioxide content of the air
Ans: The three human activities which would lead to an increase in the carbon dioxide content of the air are:
1.) Burning of coal and petrol in industries and vehicles.
2.) Breathing release CO2 in the air.
3.) Using of appliance like air conditioners etc. also release CO2.
12.) What is the greenhouse effect?
Ans: The gases like carbon dioxide and methane are responsible for trapping sunlight in the earth’s atmosphere. This will warmup the earth’s atmosphere. This is known as the greenhouse effect.
13.) What are the two forms of oxygen found in the atmosphere?
Ans: Oxygen is present in the Diatomic molecular form and the triatomic molecular form ozone (O3).
- Textbook questions:
1.) Why is the atmosphere essential for life?
Ans: The earth’s atmosphere is different from other planets which makes it possible for life to exist on the planet. The atmosphere is made up of a mixture of gases like O2, N2, and CO2 which are essential for living organisms. The atmosphere helps in controlling the temperature. Processes like Photosynthesis, respiration, combustion is possible due to the presence of atmosphere.
2.) Why is water essential for life?
Ans: Water is known as the universal solvent. All the important reactions which occur in the body require water as a medium. The living organisms are made up of 70%. Water dissolves a number of substances and is a transporting fluid in all organisms. Water is required for digestion, respiration etc.
3.) How are living organism’s dependent on the soil? Are organisms that live in water totally independent of soil as a resource?
Ans: Soil is an important natural resource as it determines the areas diversity. Apart from this soil supports the growth, reproduction and development of animals, plants and microorganisms by providing them with shelter, nutrients and minerals. Plants are mostly terrestrial organisms and their roots absorb water and minerals essential for photosynthesis from soil.
living organisms that reside in water are not totally independent of soil. This is because soil is the natural habitat of a number of decomposers as well as primary producers. These primary producers are indirectly necessary for providing essential nutrients to water. These nutrients are then consumed by aquatic living organisms
4.) You have seen weather reports on television and in newspapers. How do you think we are able to predict the weather?
Ans: The weather reports are prepared by the meteorological department. This department collects and keeps the records of the data collected for over a long period of time. Variations in temperatures, humidity, rainfall etc. are collected. This data is collected and is used in weather forecast.
5.) We know that many human activities lead to increasing levels of pollution of the air, water-bodies and soil. Do you think that isolating these activities to specific and limited areas would help in reducing pollution?
Ans: Human activities leads to pollution in the air, water and soil. Isolating these activities to specific and limited areas would help in reducing pollution as all these activities are interlinked. So, if we control air pollution, we will indirectly help in reducing water and soil pollution and vice versa.
6.) Write a note on how forests influence the quality of our air, soil and water resources.
Ans: Forest is a natural resource which has an impact on the quality of our air, soil and water resources.
i) Air quality:
- Forest release oxygen in the air and absorbing carbon dioxide. This is a natural process of air purification.
- The trees in the forests also help to reduce air pollution.
ii) Water quality:
- Water quality is also affected by the forests.
- If deforestation takes place to a large extent, then the amount of rain fall in the year will be affected, which will affect the water quality.
- They also help in replenishing the ground water reserves.
iii) Soil:
- The roots of trees hold the soil particles together preventing soil erosion.