Chapter 15, Problem 4STP

Summary Introduction

Introduction :

Any preserved evidence of an organism is known as fossil. Pants, animals and even bacteria can form fossil. There are six categories of fossils. Trace fossil, molds and casts, replacement petrified or permineralized, amber and original materials are the six categories of fossil.

Answer to Problem 4STP

Correct answer :

The correct answer is option (D) trace fossil.

Explanation of Solution

Explanation/justification for the correct answer :

Option (D) trace fossil. A trace fossil is any indirect evidence left by an organism. Some examples of trace fossil are footprints, burrows, and fossilised feces. Therefore, a dinosaur footprints in rocks is a trace fossil. Thus, this is the correct answer.

The explanation for the incorrect answer :

Option (A) cast fossil. A mold is an impression of an organism. A mold filled with sediment is a cast fossil. Thus, this is an incorrect option.

Option (B) petrified fossil. Empty pore spaces are filled in by minerals such as in petrified wood.

Thus, this is an incorrect answer.

Option (C) replacement fossil. The original material of an organism is replaced with mineral crystals that can leave detailed replicas of hard or soft parts is replacement fossil. Thus, this is an incorrect answer.