SCIENCE 3 UNIT 9 - THE TOP LAYER OF EARTH

UNIT 9 – THE TOP LAYER OF EARTH

La Ñora, Thursday 3rd April 2014.

Page 105.

4^th What is soil made up of?

Soil is made up of particles of rock and minerals, air, water and humus.

5^th What is humus?

Humus is the remains of dead plants and animals.

6^th Why are animals important to soil?

Animals are important to soil because they help turn the dead plants and animals into humus.

7^th Where can we find soil?

We can find soil on the top layer of the Earth.

Page 106.

1^st What are the three layers of soil?

The three layers of soil are topsoil, subsoil and bedrock.

3^rd Copy and complete the chart.

Topsoil	Subsoil	Bedrock
decomposers insects	less water and air small rocks	bigger rocks little water and air

Page 107.

1^st What are the three types of soil? Describe their characteristics.

The three types of soil are fertile soil, poor soil and arid soil.

·     Fertile soil has lots of humus and water. Many plants can grow well in this type of soil.

·     Poor soil has little humus and water. It has more rocks than fertile soil. Only hard plants such as olive trees can grow in poor soil.

·     Arid soil has very little humus and water. It has lots of rocks or sand. Only very hardy plants, such as cacti can grow in arid soil.

Page 108.

2^nd Copy and complete the sentences.

a.  Plants and animals are important to the soil ecosystem.

b.                       Animals, such as snails eat dead plants and animals.

c. Decomposers living in the soil help turn plant and animal remains into humus.

Page 109.

1^st Look at the photos. Find objects made from these rocks and minerals in the kitchen.

ROCKS

The blackboard on the wall is made up of slate.

The kitchen worktop is made up of granite.

The floor is made up of marble.

MINERALS

The watch is made up of gold.

Salt on the table.

Pipes are made up of copper.

Pipes are made up of copper.

OTHER

The fridge (refrigerator) is made up of metal.

Forks, spoons, knives, pots, a sink and aluminum foil are made up of metal too.

Pages 112 and 113.

1^st Copy and complete the word map.

SOIL

TYPES	COMPONENTS	LAYER
fertile poor arid	rocks minerals humus air water	topsoil subsoil bedrock

2^nd Use the word map to copy and complete the sentences.

a.    Soil can be fertile, poor or arid.

b.   Soil is made up of rocks, minerals, humus, air and water.

c.    There are three layers in the soil. The top layer is called topsoil, the middle layer is called subsoil and the bottom layer is called bedrock.

3^rd Match and write the sentences.

a.          Fertile soil has lots of humus and water.

b.         Poor soil has a little humus and water.

c.          Arid soil has very little humus and water.

4^th In which type of soil do plants grow best? Why? Copy and complete the sentence with your answer.

Plants grow best in fertile soil because it has lots of humus and water.

5^th Copy and label the diagram of the soil.

topsoil

subsoil

bedrock

6^th Copy and complete the chart. Write the names of two types of rocks and minerals. How do we use them?

Rocks and minerals	Uses
slate granite marble gold salt copper	blackboards, roofs kitchen worktops floors watches, jewels food pipes, wires