Review Test 2: Soil & Light and Vision

What is soil?

• It is the loose material in which plants can grow in the upper layer of Earth.

• It is the leaf that grows on the plant.

• It is the food that can be found inside the seed.

• It is a playground to bugs.

Why is soil an important natural resource?

• soil is used to make buildings

• soil can grow crops

• soil comes from bedrock

• soil is color brown

Soil is made of ________________.

• weathered rocks and minerals

• dead plants and animals

• air and water

• all of the above

Humus is ________________.

• the part of soil made up of decayed parts of once-living things.

• a dip that is made of garbanzo beans.

• a bone that can be found in the upper arm.

• a sound people make when their lips are together.

How do decomposers work hand-in-hand with humus?

• by removing gravel and sand from soil

• by breaking down gravel into silt

• by eating animals that may harm the soil

• by breaking down the remains of dead plant and animal matter

A gardener wants to add humus to his soil because it contains a lot of nutrients and helps retain water. What does humus form from?

• Sand

• Rocks and minerals

• Decayed animals and plants

• Volcanic lava

Soil needs every component except:

• air and water

• humus - organic material

• weathered rocks - sand, silt, and clay

• gravel

Which soil is the worst for growing plants?

• sand

• silt

• clay

• loam

This type of soil is best for plant growth.

• silt

• sand

• clay

• loam

This type of soil is sticky when wet and hard when dry.

• silt

• sand

• clay

• loam