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Unformatted text preview: 3/9 Oceanography Chapter 2 Key Ideas: The objects comprising our solar system condensed about 5 billion years ago from a thin cloud that had been enriched by heavy elements made in exploding stars o Everything in the universe was concentrated at 1 time and eventually exploded (The Big Bang). After the Big Bang, other solar systems and stars formed, lived, and died producing simple elements like Helium and Hydrogen. From those elements, other more complex elements were formed and stars exploded making supernovas leaving star dust (which is what we are composed of). Earth first had a solid surface about 4.6 billion years ago. The ocean formed from clouds of steam and water vapor when Earths surface became cool enough to allow liquid water to rest on the surface o 4.6 Billion years ago, Earth was made into a sphere and cooled , so liquid water accumulated on Earth and then life came about 4 billion years o Life began somewhere in deep ocean Life probably arose on Earth shortly after its formation, about 4 billion years ago. Earths atmosphere has changed substantially through time. The most dramatic change began about 2 billion years ago when photosynthetic organisms began producing large quantities of oxygen o Photosynthetic organisms evolved and were able to capture sunlight and convert this energy to life. This life used energy rich inorganic molecules, this process is called chemosynthesis. o As a byproduct of photosynthesis , oxygen is being released this shows a change in the atmosphere b/c now theres oxygen Important: We were formed from star dust and were made from exploding supernovas Life evolved right after water came, probably in the deep ocean Earths constantly changing Future of the Earth: Earth will begin to burn itself out, cool, expand, and consume the earth and life will disappear in numerous ways Chapter 3: Earth has periodically warmed up and cooled down Know different ways of heating: convection and conduction Chapter 4: Overtime, sea level fluctuates and continues to change. It is predicted to increase in the future What is life and what must it do? o It exists in a highly organized state in which it maintains itself, grows, reproduces, adapts to its environment, and lives within its limits To do this, it must capture, store, and transform energy (food, web, cycles) o Life modifies and transforms its environment, and in turn, life is modified and transformed by its environment o Sex and death are integral to maintain life o The first organisms produced by just dividing in half...
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- Spring '08