1. Review

2. S M U 1 R F S

3. The leftover plant and animal matter is called ( )
humus

5. A layer of soil differing from the layers above and below it is called ( ).
horizon

6. 1 point!

7. A horizon is made up of ( ). This is the top layer of soil.
topsoil

9. The B horizon is known as ( ). This is normally a fairly hard layer.
subsoil

11. The soil horizons make up a ( )
The soil horizons make up a ( ). This is a vertical section of soil from the surface down to bedrock.
Soil profile

13. ( ) is a mixture of tiny rock particles, minerals, humus, water, and air.
Soil