Soil Composition

A student is performing an investigation with different soils. The pictures show four different types of soil that will be used by the student. Which of the soils MOST likely contains the most matter from living organisms?

• Z because it has the most rock

• Y because it has the darkest color

• X because it has the largest particles

• W because it has the smoothest texture

Tags

NGSS.MS-LS1-5

Which of the following is the largest mineral particle found in soil?

• silt

• sand

• dirt

• peat

Which part of topsoil contains decayed plant and animal matter?

• silt

• sand

• humus

• clay

Tags

NGSS.MS-LS2-3

Which activity will most likely increase soil fertility?

• Worms are removed from the soil.

• A tree dies and decays.

• Plastic is buried in the ground.

• A tree is cut for lumber.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

Read the passage about earthworms.

EARTHWORMS: Earthworms are very important for producing healthy, mature soil. Worms speed up humus

production by eating decaying material. In fact, worms are put into compost piles to help make natural fertilizer for crops. Worms leave holes and tracks in the soil that are

filled with water when it rains. Worms loosen

the top layer of soil making it ideal for thriving

plants.

How do earthworms help create organic material

for healthy soil?

• Worms eat decaying material and break it into

  smaller pieces.

• Worms dry out the soil by drinking the water in

  layers.

• Worms break up rocks into smaller pieces.

• Worms help with chemical weathering.

Tags

NGSS.MS-LS2-3

Mary is taking care of the garden at school and spends most of her time pulling weeds. She wants to find a way to control the weeds that does not harm earthworms. Mary wants to save the earthworms because they

• eat the leaves of plants but give the plants water

  in return.

• protect plants from predators by releasing

  poison into the soil.

• travel long distances and help move plant seeds

  to new areas.

• break down organic material into nutrients that

  plants use to grow.

Tags

NGSS.MS-LS2-3

A student is designing an investigation that will model the formation of soil. Why is it important that the student include organic material as a component of the investigation?

• Organic material contains very small particles

  and will give the soil a fine texture.

• Organic material will be weathered by wind and

  water and become silt. Silt is needed by plants

  to create sugars.

• Organic material contains toxins that leech into

  the soil and will prevent bugs from eating the

  plants.

• Organic material will be decomposed by fungi

  and bacteria and eventually form humus. Humus

  contains nutrients that plants need to live.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

NGSS.MS-LS2-4

What is true about soil layers?

• The bottom layer of soil contains the most

  organic material.

• The bottom layer of soil is best for plant growth.

• Layers of soil get rockier as they get deeper.

• The top layer of soil is usually the rockiest.

Tags

NGSS.MS-LS2-3

Look at the diagram.

Which layer contains the majority of the bacteria,fungi, worms, and other organic matter?

• Z

• Y

• X

• W

Tags

NGSS.MS-LS2-3

Under which conditions is the thickest soil is

most likely to form?

• in a cold, wet climate

• in a cold, dry climate

• in a warm, wet climate

• in a warm, dry climate

Tags

NGSS.MS-ESS2-4