Earth History Flashcards
Earth History
How long ago did the earth form?
4.5 billion years
Earth History
How long ago was the moon created from the earth?
4.5 billion years
Earth History
How long ago did water form on earth?
4.4 billion years
Earth History
How long ago did prokaryotic life first arise on earth?
4 billion years
Earth History
The moon is a piece of what?
The earth crust/mantle
(ejected after a protoplanet crashed into the newly-formed earth)
Earth History
How long ago did photosynthesis first begin on the earth?
3 billion years
Earth History
How long ago did unicellular eukaryotic life first arise on earth?
2 billion years
Earth History
How long ago did multicellular eukaryotic life first arise on earth?
1.5 billion years
Earth History
The great oxidation event (the massive increase in oxygen in the earth’s atmosphere) 2.5 billion years ago occurred due to the rise of what?
Cyanobacteria
Earth History
What do we call the period in earth history prior to the arrival of life?
The Hadean
Earth History
What is the name of the period of earth history after the arising of life but before eukaryotes?
The Archaean
Earth History
What is the name of the period of earth history during which eukaryotes first arose and flourished?
The Proterozoic
Earth History
The Hadean, Archaean, and Proterozoic eons can all be referred to collectively as what?
The Precambrian
Earth History
Photosynthesis began on earth (and thus oxygen proliferated) in which Eon of the earth’s history?
The Proterozoic
Earth History
The Proterozoic Eon is a time when the earth became oxygen-rich, the ozone layer developed, and what form of life first appeared?
Eukaryotes