The human beings have modified the environment according to their needs. With the passage of time, they learnt to grow crops, domesticated animals and started leading a settled life. The invention of wheel, productivity, barter system, transportation-all these factors helped in bringing out a revolutionary change in the life of human beings.

Our environment is changing because of our increasing needs. We are, therefore, modifying and at times even destroying our natural surroundings.

Environment is considered as a basic life support system because it is the provider of basis necessities of life such as air, water, food, and land.

During winters, sky remains cloudy and foggy most of the time.

(i) Agriculture
(ii) Buildings
(iii) Institutions
(iv) Animal Rearing
(v) Roads
(vi) Industries

Human beings interact with environment and modify it according to their needs. They use vehicles which pollute air, they make cars, mills, factories, etc. Land is used to build factories. Water is collected for daily needs. This is how human beings modify natural environment.

The atmosphere is the thin layer of air that surrounds the Earth. The gravitational force of the Earth holds the atmosphere around it. It protects us from harmful rays and scorching heat of the Sun. It consists of a number of gases, dust and water vapour. The changes in the atmosphere produce changes in the weather and climate.

Lithosphere is the solid crust or the hard top layer of the Earth. It is made up of rocks and minerals and covered by a thin layer of soil. It is an irregular surface with various landforms such as mountains, plateaus, plains, valleys, etc. It provides forests, grasslands for grazing, land for agriculture and human settlements. It is also a source of mineral wealth.

Biosphere is a narrow zone of Earth where land, water and air interact for supporting of lives.

Plants and animals are the rwo major components of biotic environment.

The lithosphere is the outermost solid surface of the Earth which made up of rocks and minerals and covered by a thin layer of soil.

Buildings, parks, bridges and roads are four examples of human-made environment.

The environment comprises of three major components
(i) Natural components are land, water, air and living things.
(ii) Human-made components are buildings, parks, bridges, roads, monuments and industries.
(iii) Human components are individuals, religions, political situation, family, education, community and economy.

The natural environment is encircled by the world of living organisms (e.g. plants and animals) and world of non-living things (e.g. land).

An ecosystem is a system which is formed by the interaction of living and non-living things. They are connected by the transfer of energy and materials.