How did the Universe Form?

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How did the Universe Form?
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• The universe formed 14 billion years ago from an
  explosion referred to as the Big Bang
• The universe is constantly expanding
• http//www.brainpop.com/science/space/bigbang/zoom
  .weml

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How did our solar system form?

• Our solar system formed when the Big Bang
  explosion cooled.

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How did Earth form?

• Earth formed when dust, gases, and ice particles
  from the Big Bang collided, 4.6 billion years ago
  (4,600 million years ago).
• http//www.teachersdomain.org/ext/ess05_img_wallof
  time/index.html

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What keeps Earth from being bombarded with space
debris?

• Earths atmosphere and magnetic field protects it
  from being bombarded by space debris.

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When did humans appear on Earth?

• Humans appeared on Earth very, very recently
  about 100,000 years ago.

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How do we know what life existed on Earth before
humans?

• Fossils tell us what life forms existed before
  humans.

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What is a fossil?

• http//www.brainpop.com/science/diversityoflife/fo
  ssils/quiz/

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• A fossil is
• Body fossil-
• Trace fossil-
• Mold-
• Cast-
• Petrified fossil-

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• A fossil is the preserved remains or traces of an
  organism that lived in the past.

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• Body fossil- part of original organism that has
  been preserved ex bug in amber, mammoth in ice
  saber-toothed tiger in tar pit

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• Petrified fossil- formed when minerals slowly
  replace an organism

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• Mold- hollow print, impression in sediment which
  turns to rock

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• Cast- when minerals fill in a mold and harden
  into rock 3-D

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• Trace fossil- footprints, nests, bite marks, poop
  (what an animal could leave behind)

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How are fossils formed?

• http//www.teachersdomain.org/folder/view/3748/

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How can we find out how old a fossil is?

• http//www.teachersdomain.org/resource/tdc02.sci.p
  hys.matter.radiodating/

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What can fossils tell you about how life changed
through time?
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What are some things that you want to understand
better about fossils and changes in life through
time?