Class-8 Social Science Chapter-27 Our life and Environment

 EVENTS CONVENT HIGH SCHOOL

01/02/2021             CLASS-8                   SLOT-2

SOCIAL-SCIENCE
Chapter-27 OUR LIFE AND ENVIRONMENT

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1.   Choose the correct alternative from the following:

Question 1.Is not a biodegradable waste:

(a) vegetables

(b) fruits

(c) paper

(d) polythene bags

Answer:

(d) polythene bags

 

1.   Short Answer Type Questions

Question 1.What are industrial waste? Give examples.

Answer: Almost every industry generates different types of wastes, many of which are hazardous to all types of life. The wastes can be solid, liquid or gaseous. These wastes can cause destruction to the environment. The waste material contains ignitable, corrosive, reactive and topic elements. Examples, as, dust, sulphuric acid, hydrochloric acid, SO2, CO2, CO2 gases and plastic waste etc.

 

Question 2.What are the processes of manufacturing of goods?

Answer:Manufacturing of goods involve three processes.

1. Assembly:It is the combinations of parts to make the final product, for example, a bicycle is assembled by joining various parts.

2. Alteration:It is the modifying of the raw material into a new material or final product for example sawing of trees into lumbar.

 3. Extraction:In this process one or more components from the raw material for example petrol is extracted from the crude oil.

 There are many proofs of early production like bricks used in the buildings earthen pots to store grains etc. All there were produced with hands. As civilization grew the method of production improved because of innovation for example fibres take from different sources are processed to forms cloth.

 

Question 3.Name the major components of industry?

Answer:Most of the manufacturing industries need four imparts capital, raw material, technology and labour.

1. Capital:Every industry needs two types of capital Finance capital and physical capital. The physical capital is building, machinary etc and finance capital is money.

2. Raw Material:Most of the industries rely on raw materials provided by natural resources. These natural resources may be renewable on non renewable.

3. Technology:The technology advancement have hed to tremendous industrial growth innovations in the field of technology can transform the culture of the society.

4. Labour:It refers to the workforce. Labour unions are formed who negotiate their wages and work with the owners.

 

Long Answer Type Questions

Question 1.How does agriculture and cattle affect the environment?

Answer:In modern agriculture use of fertilizers is increasing day by day in order to enhance the production. Fertilizer are beneficial for increasing the production of foodgrains, it has an advance effect on environment 60% of fertilizers are used by plants, remaining fertilizer gets soluble in rain water and reaches lakes, revised and ponds by which the surface good ground water.

 

This gets polluted, various insecticides and pesticides which protect the crop from insects and diseases pollute the environment. Cattle are reared in large number to get animal products. Increasing number of cattle has adverse effect. Artificial reproduction of animals through cloning produce economically lucrative breeds, it may lead to diminishing bio-diversity.

 

Question 2.Explain the methods of solid waste disposal?

Answer:The various methods of solid waste disposal are:

 1. Recycling:It is very old method in which the waste materials are made reusable. All the metal products can be melted to make new products. Plastic, glass and paper is roofs recyclable.

 2. Landfill:It is the common method of disposing waste on land. It is also the cheapest means because transport cost is the only major expenditure. In a modem landfill the solid waste is spread in this layers. Each layer is solidified by bulldozer before the next layer is deposited on them trees are planted there.

3. Composting: It is a process of decomposing solid waste to make fertilizers. Biodegradable waste is decomposed by microorganisms and it is used as a manner.

4. Incinerators: In the incinerator the waste is burned so that it reduces weight and volume around 90%.

 Question 3.What do yo understand by environment friendly technology? Explain.

Answer:Modern technology can makes industries safe and cost effective. Modern technology is designed to recycle the various component of manufacturing system.

For example:The scrap steel of automobile industry can be useful to mixed with other metals produce a new metal.

The smoke scrubbers remove all the dangerous gases and particulate matter from the discharge of industrial plants.

Question 4.Describe the natural and regional environmental issues?

Answer:National environmental issues. The govt, of India has created agencies to check the pollution and has passed Environment Protection Act, Factories Amusement Act, Central Motor Vehicle Trucks etc. Govt, agencies as well as NGO’s work to check the pollution govt, of India provided enough money for functioning these agencies and departments.

Pollution Central Board at national level as well as state level has been established. These boards has been authorised to survey the area and fix the responsibility. The guilty is persisted in the court.

Regional environmental issues:At this level a variety of steps have been taken by the govt. NGO’s for the convservation of environment. At local level the municipality or municipal corporations plays a direct role in the water disposal. The sewage of the city is drained to distant parts from the city.