Ch 9 Science Review

The layer of soil that contains humus is called _____.

• bedrock
• topsoil
• subsoil

The layer in which most plants grow is called _____.

• bedrock
• topsoil
• subsoil

The layer that is made of solid, unweathered rock under layers of soil is called _____.

• bedrock
• topsoil
• subsoil

Small bits of weathered rock and other material is called _____.

• abrasion
• humus
• sediment

Sediment that is deposited at the mouth of a river makes the mouth of the river _____.

• deeper
• narrower
• shallower

The moving of bits of weathered material from one place to another is called _____.

• gravity
• erosion
• sediment

The dropping of sediment in a new place is called _____.

• deposition
• landforms
• abrasion

An area of sediment that builds up at the mouth of a river is called ______.

• delta
• a butte
• an avalanche

Soil is made of ______.

• water, humus, and fossils
• weathered rock, air, and mesas
• weathered rock, water, air, and humus

Two types of landforms are _____.

• mountains and dunes
• gorges and rivers
• dunes and lakes