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16 Cards in this Set
- Front
- Back
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1. Name the parts of the earth |
• Core Inner/Outer • Mantle • Crust |
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2. Alfred Wegener put forward the idea of continental drift and that the continents existed as one super continent. What evidence did he have? |
• Shape of the continents look like they could fit together like a jigsaw puzzle • Fossils from different continents matched up. |
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3. Why were his ideas not accepted? |
• Not enough evidence • The believed the earth was shrinking as it cooled. |
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4. What are the names of the plates making up the earth’s crust? |
• Tectonic plates |
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5. What causes them to move? |
• Convection currents in the mantle |
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6. What causes the convection currents? |
• Radioactive processes in the core cause the mantle to heat up causing the convection currents |
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7. Why can scientists not predict where and when earthquakes occur? |
• The changes occur inside the earth’s mantle which scientists cannot measure. |
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8. The composition of the atmosphere has been has been much the same as it is today. What is the composition of the atmosphere? |
• About 78% Nitrogen • About 21% Oxygen • Small proportions of carbon dioxide water vapour and argon |
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9. What is thought to have created the early atmosphere? |
• Intense volcanic activity released gasses that formed the early atmosphere • And water vapour that condensed to form the oceans |
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10. What was the composition of the early atmosphere? |
• Mainly Carbon Dioxide • Water vapour • Small proportions of methane and ammonia • Little or no oxygen |
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11. What is thought to have led to the production of the oxygen in today’s atmosphere? |
• Photosynthesis by plants and algae • They absorbed carbon dioxide • Produced oxygen |
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12. What happened to most of the carbon dioxide in the atmosphere? |
• It was ‘locked up’ in sedimentary rock (like calcium carbonate) • Locked up in fossil fuels |
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13. What part do the oceans play in the change in carbon dioxide concentration? |
• The oceans absorb some carbon dioxide • But this can affect the marine environment |
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14. What is the impact of burning fossil fuels? |
• Burning fossil fuels releases carbon dioxide • Carbon dioxide is a greenhouse gas • This leads to global warming |
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15. What is one theory about how life on earth began? |
• From the interaction between hydrocarbons ammonia and lightening |
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16. What was the Miller-Urey experiment? |
• A mixture of ammonia and water and methane and hydrogen was subject to a high voltage spark for 1 week • Amino acids were formed and they are the building blocks of life |
