Tree sap that has hardened is called _________________________.

When an organism no longer exists it is __________________________________.

These organisms are extinct, but used to be found in the ocean.

When wood molecules get replaced by minerals, this type of fossil is formed.

A print or mark on the surface of a rock is known as an ________________________.

A mineral fossil made inside a mold is called a _______________________.

A space left in a rock where a natural object once was is known as a _______________________________.

Remains or impressions of extinct organisms are known as _____________________________.

The fossil of a footprint of an animal is called a _________________________.