Soil

Which layer of soil is on the bottom?

• topsoil
• subsoil
• bedrock
• bottomsoil

Which of the following is NOT one of the three layers of soil?

• topsoil
• undersoil
• subsoil
• bedrock

What is the layer of soil just below the topsoil?

• soil
• subsoil
• topsoil
• terrace farming

What is soil?

• A mixture of minerals
• A mixture of water, minerals, gases and organic matter
• A type of rock
• A type of bacteria

Soil is made of

• weathered rocks and minerals
• dead plants and animals
• air and water
• all of the above

When plants, animals, and other organisms die, they break down and become part of the soil. What is this part of the soil called?

• sand
• silt
• clay
• humus

Movement of soil and rocks from one place to another is called...

• weathering 
• humus
• erosion

Breaking down or wearing away of rocks is called....

• weathering
• humus
• erosion 

The movement of rocks and weathered materials is called_________.

• Chemistry
• Physical
• Weathering
• Erosion

the fertile, upper part of the soil

• clay
• sand
• silt
• topsoil