Soils and weathering

Organic matter is made of materials that….

• Were once living
• Were once nonliving
• Were once living and nonliving

Which of the following is NOT an organic material

• Worms

• Decayed animals

• Minerals

• Decayed plants

The two main factors that determine the rate of weathering are the TYPE of rock and_____.

• Music
• Climate
• Size of rock
• Weight of rock

The movement of rocks and weathered materials is called_________.

• Chemistry
• Physical
• Weathering
• Erosion

The process by which rocks break down as a result of chemical reactions/ common causes are water, weak acids, and air

• Mechanical Weathering 
• Chemical Weathering

Which layer of soil is on the bottom?

• topsoil
• subsoil
• bedrock
• bottomsoil

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

• topsoil

• undersoil

• subsoil

• bedrock

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

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

• weathering
• humus
• erosion 

the fertile, upper part of the soil

• Subsoil

• bedrock

• silt

• topsoil