Page 188 - New Medley 3 Semester 2

Soil contains minerals that are needed for plant growth. Plants absorb these

minerals through their roots. Hence, soil is very important to us and to other
living things. We depend indirectly on soil for our food.

ROCKS

e large pieces of stones found in nature are called

rocks. ere is a huge variety of rocks in nature. Some
of them are very useful to us. Just check the slab of

your kitchen. What is it made up of? Granite or marble?

Well, both of them come from di erent rocks. You will
be surprised, even diamond is a rock! It is the hardest
rock on the earth. Sharp diamond tips are used to cut Kitchen with granite slab

hard material like ‘glass’ and other stones.

Most stones that you see in jewellery are made from

various rocks. ese are called gems. e rocks are cut
into various shapes and then polished to make gems.

is is why rocks are rough and gems shine brightly.
2 Rings with different types of gems
• Critical Thinking

Unscramble these letters to nd the terms related to soil.
1. ODCKREB

2. BUSOILS

3. USHMU

AT ONE GO

 Different types of soil differ in the size of their grains.
 Loam is the best soil to grow plants.
 The different layers of soil are topsoil, subsoil, weathered parent material and bedrock.
 Plants need good soil to grow well.

REMEMBER THESE TERMS

Parent material : The material from which soil is formed
Humus : Dead and rotting parts of plants and animals
Decay : To rot
Loam : Soil having equal amounts of sand and clay

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