CH. 13 Geological Time

The time it takes half of the atoms of a radioactive element to decay

• relative age
• half-life
• absolute age
• radioactive decay

Preserved remains or traces of an organism that lived in the past.

• vertebrate
• carbon film
• invertebrate
• fossil

Which letter matches with the OLDEST layer of rock?

• W

• X

• Y

• Z

What division of time was the longest ?

• Paleozoic

• Mesozoic

• Cenozoic

• Precambrian

When did Precambrian time end

• 542 million years ago

• 4.5 Billion years ago

• 3.65 Billion years ago

• 3.8 Billion years

What era did dinosaurs go extinct ?

• Paleozoic

• Mesozoic

• Cenozoic

What is the geological time scale ?

• A clock

• A calendar

• Something that divides Earths history into groups

What period did new species rapidly evolve in shallow seas ?

• Devonian

• Jurassic

• Cambrian

The earth is ______________of years old

• Hundreds

• Millions

• Billions

• Trillions

Mammals are a dominant group in which era?

• Cenozoic

• Mesozoic

• Paleozoic

• Cambrianozoic