Science Unit 5 Review

Front

What is a mass extinction?

Back

A mass extinction is when many species become extinct over a short period of geologic time.

Front

How do index fossils help determine the age of a rock layer?

Back

Index fossils help determine the age of a rock layer because they formed at only one particular time.

Front

What is relative dating?

Back

Relative dating is a method used to determine the age of rocks and fossils by comparing their placement in layers.

Front

What makes a good index fossil?

Back

A good index fossil is one that lived in many areas and existed for a short period of time.

Front

What does the fossil record refer to?

Back

The fossil record refers to the fossils in the rock layers on Earth.

Front

What is an example of an index fossil?

Back

An example of an index fossil is a dragonfly that lived in large populations during the end of the Paleozoic.

Front

Why are index fossils important in geology?

Back

Index fossils are important because they help geologists determine the relative ages of rock layers.

Front

What is the significance of the Cenozoic period?

Back

The Cenozoic period is significant because it is the most recent geological time period, known for the dominance of mammals.

Front

How can you demonstrate relative dating with newspapers?

Back

You can demonstrate relative dating by describing the placement of the papers within the entire stack.

Front

What is the difference between absolute dating and relative dating?

Back

Absolute dating gives a specific age of a rock or fossil, while relative dating places them in order without exact dates.