Earth's History Review

The oldest eukaryotic fossils are about how many years old?

• 2.1 million

• 2.1 billion

Cell differentiation provides a way for organisms to grow bigger and stronger over time.

• True

• False

The leading theory to explain the complex inside of eukaryotic cells is the ______.

• Big Bang Theory

• Endosymbiotic Theory

Prokaryotes are microscopic organisms that can survive in extreme environments.

• True

• False

Eukaryotes are the oldest known fossils on our planet.

• True

• False

The ozone layer began to form about 2.5 billion years ago.

• True

• False

Which type of UV rays does the ozone filter out?

• UV- A

• UV- B

How many molecules of oxygen are in ozone?

• 2

• 3

Large amounts of Sulfur - 33 are found in rocks that are younger than 2.4 billion years.

• True

• False

When were most of the redbed formations formed in North America?

• 2 billion years ago

• 260 million years ago