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43 Cards in this Set
- Front
- Back
When was the Big Bang? |
13-14 Billion years ago |
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What happened within one second after the Big Bang? |
Protons, Neutrons, and Electrons formed |
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Protons |
Positive charge, found in nucleus |
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Neutrons |
No charge, found in nucleus |
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Electrons |
Negative charge, in orbit around the nucleus |
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What happened 300,000 years after the big bang? |
Protons, neutrons, and electrons clump together to form the hydrogen atom |
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What is Hydrogen made from? |
1 proton, 1 electron |
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What is Helium made from |
2 protons, 2 neutrons, 2 electrons |
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What happened one billion years after the big bang? |
Hydrogen clouds are clumping together to form galaxies and stars |
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How old is the sun? |
5 billion years old |
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How hot is the sun? |
28 million degrees Fahrenheit at the core |
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Where does the sun get its energy? |
By turning hydrogen into helium through nuclear fusion |
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What are the two must abundant elements in the sun and universe? |
Hydrogen and Helium |
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How old is the moon |
4.6-4.0 billion years old |
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How did the moon form? |
A mars sized planet slammed into Earth |
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General characteristics of moon |
No atmosphere, cold interior, no magnetic field, some ice at poles |
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What is the moons main influence on earth? |
It creates the tides |
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How old is the Earth? |
4.6 billion years old |
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General characteristics of Earth |
Hot interior, atmosphere, liquid water, ice, water vapor, magnetic field |
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How does the Earth's magnetic field protect the Earth? |
By blocking charged particles coming from the sun (solar wind) |
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Where does the Earth get interior heat? |
From radioactive decay of elements in Earth's atmosphere |
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The Earth has an atmosphere, where did it come from? |
Gases released when the Earth's mantle was compressed into distinct layers |
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Early atmosphere |
Very little free oxygen, lots of water vapor, lots of carbon dioxide |
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Atmosphere today |
Lots of oxygen, little water vapor, little carbon dioxide |
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What caused an increase in the amount of oxygen gas? |
The evolution of photosynthesis |
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What causes a decrease in the amount if carbon dioxide |
Carbon is tied up in living and dead organisms, photisynthesis carbon dioxide to make sugars |
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What is currently increasing carbon dioxide |
The burning of fossil fuels releases the stored carbon, animals exhale carbon dioxide |
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What layer of atmospheric gas protects life on Earth? |
The ozone layer |
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What does the ozone layer protect against? |
Ultraviolet light |
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How us the ozone layer formed? |
Oxygen gas joins with free oxygen in the upper atmosphere to produce ozone |
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How high is the ozone layer |
31 miles |
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How thick is the ozone layer |
When compressed, a few millimeters thick |
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How much of the Earth's surface is covered by water? |
75% |
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How much of Earth's water is salt water? |
97% |
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How much of Earth's water is fresh water? |
3% |
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How much of Earth's water is drinkable? |
Less than 3% |
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How old is the origin of life on Earth? |
3.5 billion years ago |
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How old is the origin of oxygen-releasing photosynthesis |
About 3.5 billion years ago |
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How old are eukaryotic cells? |
About 1.5 billion years ago |
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How old are the first land plants? |
About 500 million years old |
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How old are the first land animals? |
500 million years old |
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When did the evolution of mammals begin? |
200-250 million years ago |
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When was the evolution of anatomically modern humans? |
200 thousand years ago |