Geologic Time Lesson 3: Precambrian

Where did oxygen in Earth's atmosphere come from originally?

Which of the following was not present in early Earth?

What HAPPENS during photosynthesis?

Scientist think the Earth is ___ years old.

Are archaea multicellular or unicellular?

What is the type of extremophile that lives in very salty environments, such as the Great Salt Lake.

an organism that has adapted to living in very high temperatures (heat), such as bacteria or algae

What do you call an organism that thrives in acidic environments.

Organisms that can live in extreme environments are called:

There are an abundance of fossils from precambrian time.