Social Science VSQ (2 Marks)

Plants and animals depend on each other for their own sake. Plants release oxygen that animals breathe and observe carbon dioxide that animals release.

Man modifies his environment according to their need. With time needs grew and became more varied. Humans learn new ways to use and change environment. They learn to grow crops, domesticate animals and lead a settled life.

Natural environment consists of land, water, air, plants and animals. Thus, natural environment refers to both biotic (plants and animals) and abiotic (land) conditions that exist on the earth.

Biotic Environment:

• The world of living organisms is called biotic environment.
• Examples: Plants and animals.

Abiotic Environment:

• The world of non-living elements is called abiotic environment.
• Example: Land.

All the objects created by nature comprise of natural environment .It includes both biotic as well as abiotic condition existing on earth. Lithosphere, hydrosphere, atmosphere are the domain of natural environment.

Camels, snakes, lizards, insects are found in deserts.

Whatever we see in our surrounding that is environment. Environment is our basic life support system .It provides the air we breathe, water we drink, the food we eat and the land where we live.

The relationship between the living organisms and their surroundings form the ecosystem. Rain forest, grassland, deserts, mountains, lake, river, ocean and pond are some of the examples of ecosystems.

Biosphere: Plants and animals found in the narrow strip at the junction of lithosphere, atmosphere and hydrosphere together make biosphere.

Water covers a big area of the earth's surface and this area is called hydrosphere. It comprises various sources of water and different type of water bodies like river, lakes, seas, ocean etc.

The basic components of natural environment are- land, water, air, plants and animals.

The hydrosphere is water found on, under, or over the surface of a plane on earth. The different components are: lake, river, ocean etc.

Difference between biotic and abiotic environment.

S.No.	Biotic Environment	Abiotic Environment
1.	The world of living organisms.	The world of non-living elements.
2.	Example: plants and animals.	Example: land.

The oxygen is the second most plentiful gas in the air. Humans and animals take oxygen from the air. Green plants produce oxygen during photosynthesis.

Air is neither an element nor a compound. It is a complex mixture of gases and there are also a number of non gaseous substances present in it.

Lithosphere provide us forests, grasslands for grazing land for agriculture and human settlements. It is a rich source of minerals.

Kerala, a southern state of India gets ample rainfall. It has lush green vegetation and coconut plantations.
Rajasthan, on the other hand, gets very less rainfall. It has thorny bushes, kikar and babul as vegetation.

Environment provides the basic life support system like air, water, food and land. The man made things like car pollute the air, factories build on land, containers for food and water are the examples of modification of environment.

Ecosystem: An ecosystem is formed by the interaction of all living organisms with one another and with the physical and chemical factors of the environment in which they live. All are linked by transfer of energy and material. They are interdependent.

Carbon dioxide, helium, ozone, argon and hydrogen are found in lesser quantities.

Ravi was upset at losing his playground to building construction. Nurie invited him to her home in Mizoram in the lush green surroundings.

Green plants use carbon dioxide to make their food and release oxygen. Human or animals release carbon dioxide.

Plants provide shelter for animals and they provide oxygen for the animals to live. When animals die they decompose and become natural fertilizer for plants. Animals also help in pollination and seed dispersal.

Certain things are used in a certain way like watermelon in summer or roasted peanuts in winter. We need a balance between natural and human environment. Human beings must use their natural environment in a sustainable way to maintain the balance.

Land, air, water, plants and animals are all the part of natural environment.

The world of living organisms is known as biotic environment. Example: plants and animals.
The world of non-living element is known as abiotic environment. Example: land.

Barter system is a method of trade in which goods are exchanged without the use of money.

Biotic environment: The world of living organisms is called biotic environment. For example plants and animals.
Abiotic environment: The world of non living elements is called abiotic environment. For example land.