Earth's processes Flashcards
What is the largest time division called?
An Eon
What can each Eon be sub divided into?
Eras
What can each Era be sub divided into?
Periods
List the Eons of Earth History in reverse Chronological order.
1) The Phanerozoic Eon
2) The Proterozoic Eon
3) The Archaean Eon
4 The Hadean Eon
How old is the Earth believed to be?
4.6 Billion years old
List what was different from today’s Earth to the Earth of 4 billion years ago.
- Strong U.V rays from the sun
- Atmosphere of water vapour, methane, ammonia, carbon Dioxide, nitrogen, hydrogen.
- NO free oxygen
- Violent Storms - A lot of lightning
- Volcanoes added many gases to the atmosphere.
Who proved the concept that “life could appear spontaneously” and when?
Louis Pasteur in 1862
What did Louis Pasteur’s experiment consist of?
It consisted of 3 flasks containing a “broth” boiled until sterilised. There was a closed flask, open flask and a flask with a gooseneck.
What were the results of Louis Pasteur’s experiment in 1862?
It proved the theory of spontaneous regeneration wrong
When the the CELL THEORY OF LIFE established as a scientific principle?
By the 1880’s
What did the Cell theory of life include?
All cells (life) come(s) from pre existing cells (life).
What is the Panspermia Hypothesis?
The idea of that the first living thing may have come from outer space.
What is evidence for the Panspermia hypothesis?
Certain organic chemicals including some which can form amino acids have been detected in comets, meteorites and even interstellar dust clouds.
What is wrong with the Panspermia hypothesis?
It does not explain how life started before it came to Earth.
When was the Urey-Miller experiment designed?
The 1950’s