2.2.1 Soil Composition

Multiple Choice

Why are living things important for the formation of rich soil?

• They help radically change the nature of soil and create a rich ecosystem.

• They only add color to the soil.

• They make the soil harder and less fertile.

• They prevent any plants from growing.

Multiple Choice

Which of the following is NOT a component of undisturbed soil according to the pie chart?

• Organic Matter

• Water

• Air

• Gravel

Multiple Select

Which of the following statements about sand is/are correct?

• Sand is the largest soil particle.

• Sand is mostly made of silica.

• Sand is not considered soil due to its size.

• Sand helps with free movement of air in soil.

Fill in the Blanks

Pore space refers to the amount of space between

particles.

Multiple Choice

What is one key difference between soil on Earth and soil on Mars?

• Earth soil has an organic component, while Mars soil does not.

• Mars soil is richer in nutrients than Earth soil.

• Earth soil is redder in color than Mars soil.

• Mars soil contains more water than Earth soil.

Multiple Choice

Soil is made of

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

Multiple Choice

Which soil would retain the most water?

• loam

• sand

• silt

• clay

Multiple Choice

Which soil would retain the least amount of water?

• gravel

• silt

• sand

• clay

Multiple Choice

The texture of soil depends on

• How much water it can retain

• Particle size

• Soil color

• Soil mass

Multiple Choice

Students wanted to test out the capacity to retain water. They poured water through the soil samples and waited for 2 minutes. Based on the results, which of the following is a correct conclusion?

• Water seeped through sample A the slowest

• Water seeped through sample B the fastest

• Sample A retained the most water

• All samples retained the same amount of water

Multiple Choice

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