Students can download Class 8 Geography Chapter 5 Biosphere Important Questions, KSEEB Class 8 Social Science Important Questions and Answers helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.
Karnataka State Syllabus Class 8 Social Science Geography Important Questions Chapter 5 Biosphere
Question 1.
What is biosphere?
Answer:
Biosphere is the part of the earth where life exists. It is the fourth component of the earth and it is the totality of all living things on earth.
Question 2.
What is ecology?
Answer:
Ecology is the study of the interaction of living organisms with their physical, chemical and biological environment.
Question 3.
What is ecological balance?
Answer:
In a natural environment there is a perfect balance between various organisms living together in the biosphere. This is known as ecological balance.
Question 4.
What is eco-system?
Answer:
Eco-system is a community of plants and animals together with their immediate environment including the inanimate part of that environment. It is also defined as ‘the total assemblage of components entering into the interactions of a group of organisms’.
Question 5.
What is environment? Mention the two types of environments.
Answer:
Environment is the surroundings where an organism, a community or an object exists. It creates favourable conditions for the existence and development of all living organisms. Environment is of two types – Natural or geographical and cultural or man-made.
Question 6.
What is environmental pollution? What are its causes?
Answer:
Environmental pollution is the unfavourable alteration of our surroundings, wholly or partly by human action through direct and indirect effects. Factors like over-population, industrialization, urbanization, over-exploitation of resources, consumerism, etc., are the main causes for environmental pollution.
Question 7.
Give examples for visible and non-visible pollutants.
Answer:
Visible pollutants are – smoke, gases, dust, garbage, sewage, etc. Non-visible pollutants are – bacteria, toxic chemicals mixed in water, food, soil, etc.
Question 8.
Which are the different types of environmental pollution?
Answer:
Environmental pollution is of different types. On the basis of pollutants and medium of pollution they can be classified into the following types: Air pollution, Water pollution, Soil pollution and Noise pollution.
Question 9.
What is air pollution? List the different sources of air pollutants.
Answer:
The World Health Organization defines air pollution as – substances put into air by the activity of mankind in concentration sufficient to cause harmful effects to his health, vegetation and property’. The important sources of air pollutants are:
- Natural: Volcanoes, forest fires, cosmic dust, etc.
- Man-made: Gases from industries, domestic use, automobiles, mining, nuclear power plants, nuclear explosions, etc.
Question 10.
What are the effects of air pollution?
Answer:
Air pollution causes changes in weather and climatic conditions, ozone depletion, greenhouse effect, global warming, affects human health, problems of. respiratory system, affects life of animals and plants.
Question 11.
What are the measures to contain air pollution?
Answer:
Air pollution can be contained by controlling gaseous pollutants, controlling emission from vehicles, planting more trees, using non-conventional energy sources and educating people about the consequences of air pollution.
Question 12.
What is water pollution? What are the sources of water pollution?
Answer:
Water pollution is ‘alteration in physical, chemical and biological characteristics of water which may-have harmful effects on human and aquatic life’. The important sources of water pollution are:
- Natural: Soil erosion, landslides, volcanic eruptions, decay and decomposition of plants and animals, etc.
- Man-made: Industrial effluents, urban waste, domestic waste, agricultural waste, oil spill, thermal waste, offshore drilling, etc.
Question 13.
What are the effects of water pollution?
Answer:
Water pollution spreads water-borne diseases and epidemics like cholera, typhoid, diarrhea, jaundice, etc. It also causes death of aquatic life, affects irrigation water and crops.
Question 14.
What are the measures to control water pollution?
Answer:
To control water pollution industrial effluents must be treated, drinking water sources should be kept clean, sewage treatment plants must be set up and disposal of waste into water bodies should be banned.
Question 15.
What is soil pollution? What are its effects?
Answer:
Soil pollution is decrease in the quality of soil either due to human sources or natural sources or both. Soil pollution decreases the fertility of soil and converts the land into wasteland, destroys the micro organisms in the soil, etc.
Question 16.
What are the measures to control soil erosion?
Answer:
Measures to control soil erosion are
- Controlled and judicious use of chemical fertilizers, pesticides and insecticides.
- Proper disposal of industrial and urban waste.
- Proper use of land and crop management.
- Awareness programmes on proper soil utilization and its maintenance, etc.
Question 17.
What is noise pollution? What are the sources of noise pollution?
Answer:
Noise pollution is any undesirable or harmful sound in the atmosphere leading to health hazards. The natural sources of noise pollution are – thunder, heavy rainfall, storms, hail-storms, waterfalls, ocean waves, etc. The man-made sources are – industrial noise, automobiles, air planes, mining, loud speakers, horns, domestic noise, etc.
Question 18.
What are the effects of noise pollution?
Answer:
Noise pollution can cause temporary or permanent hearing problems, headaches, restlessness, cardiovascular diseases, psychological disorders, behavioural changes, lack of concentration, etc.
Question 19.
Suggest measures to control noise pollution.
Answer:
To reduce noise pollution
- industries must be located away from residential areas
- Construction of soundproof walls in factories.
- Restricting unnecessary use of sirens, horns and loud speakers.
- Airports should be located away from residential zones.
- Providing protective equipment to workers in factories, etc.
Question 20.
What is ‘global warming’?
Answer:
The temperature of the earth has increased slowly over the last few years. This phenomenon is termed as ‘global warming’. This is the effect of greenhouse gases and trapping of heat by the atmosphere. As a result of this warming, the climatic zones are shifting, glaciers are melting and sea level is rising.
Question 21.
What is ‘Greenhouse effect’? Explain.
Answer:
The energy that the earth receives from the sun has to be balanced by the radiation emitted from the earth’s surface. The use of fossil fuels is increasing the greenhouse gases in the atmosphere. These gases trap the heat radiated from the earth. The increasing greenhouse gases add to the rising temperature of the earth and cause ‘Greenhouse effect’.
Question 22.
What is ozone? What are its uses? What causes ozone depletion?
Answer:
Ozone is a thin layer of gas found in the stratosphere. Ozone absorbs ultraviolet rays and protects all forms of life on earth. In recent years, use of air conditioners, refrigerators, sprays and deodorants is destroying the ozone due to the synthetic chemicals released into the atmosphere, primarily chlorofluorocarbons.
Question 23.
What is acid rain? Explain.
Answer:
Acid rain is rain polluted by acid that has been released into the atmosphere from factories and other industrial processes. Acid rain contains high amounts of acids, particularly sulphuric acid and carbon monoxide. It is caused when raindrops pass through the polluted atmosphere.
Acid rain kills marine organisms, damages forests and agricultural crops. It also damages old buildings and monuments. Acid rain is also referred to as ‘lake killer’.
Question 24.
What is bio-diversity? Why is conservation of biodiversity important?
Answer:
The variety of flora and fauna in a region is known as bio-diversity. Distribution of different species of plants and animals in a region shows the richness of bio-diversity.
Maintenance of biodiversity is important both for the quality of environment as also for human survival. Conservation of bio-diversity is-also important to save and protect rare plant and animal species.
Question 25.
Define the following:
Answer:
- Biosphere: Biosphere is the part of the earth where life exists.
- Ecological imbalance: Ecological imbalance is the imbalance caused when a natural or human activity disrupts the natural balance of an ecosystem.
- Global warming: Long-term increase in the temperature of the earth is called global warming.
- Greenhouse effect: The greenhouse effect is the problem caused by increased quantities of gases such as carbon dioxide in the air. These gases trap the heat from the sun, and cause a gradual rise in the temperature of the earth’s atmosphere.
- Ozone depletion: Ozone depletion refers to the gradual thinning of earth’s ozone layer in the upper atmosphere caused by the release of harmful chemical compounds and other human activities.
- Acid rain: Acid rain is rain polluted by acid that has been released into the atmosphere from factories and other industrial processes.
Multiple Choice Questions
Question 1.
The study of the interaction of living organisms with their physical, chemical and biological environment is called
(A) Biology
(B) Ecology
(C) Environment
(D) Biosphere.
Answer:
(B) Ecology
Question 2.
All plants and animals together with their immediate environment including the inanimate part of that environment is called
(A) Environment
(B) Eco-science
(C) Eco-system
(D) Geography.
Answer:
(C) Eco-system
Question 3.
The unfavourable alterations taking place in our surroundings is called ________ pollution.
(A) air
(B) water
(C) noise
(D) environmental.
Answer:
(D) environmental.
Question 4.
Which one of the following causes air pollution?
(A) Carbon dioxide
(B) Ozone
(C) Oxygen
(D) Nitrogen.
Answer:
(A) Carbon dioxide
Question 5.
Carbon dioxide and some other gases trap the heat radiated by the earth and cause
(A) global warming
(B) ozone depletion
(C) greenhouse effect
(D) acid rain.
Answer:
(C) greenhouse effect
Question 6.
The release of chlorofluorocarbons by the Use of refrigerators, air conditioners, deodorants, etc., are destroying the ________ of the atmosphere.
(A) crust
(B) mantle
(C) continental crust
(D) ozone layer.
Answer:
(D) ozone layer.
Question 7.
Acid rain is also called
(A) lake killer
(B) black rain
(C) blizzard
(D) hailstorm.
Answer:
(A) lake killer
Question 8.
The natural pollutant among the following is
(A) urban waste
(B) volcano
(C) domestic waste
(D) nuclear plants.
Answer:
(B) volcano
Fill In The Blanks
- The only planet on which life exists is earth
- The fourth component of the earth is biosphere
- The sum total of all surroundings of a living organism is called environment
- The thin layer of gas found in the stratosphere is ozone
- The rise in the temperature of the atmosphere is called global warming
- The ozone layer protects living beings on the earth by absorbing ultraviolet rays
- The variety of flora and fauna in a region is known as biodiversity
- Garbage waste is the best example of soil pollution.