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Young Voices for the Planet DVD in our online store includes 8 films where students speak out and take action on climate change.
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What is Life?

What is life? Does this seem like a strange question to you? Well, let's think about it. If you had to explain to someone what "life" is, what would you tell them?

Do all living things move? Do they eat and breathe? Even though we all seem to know what is meant by saying something is "alive", it's not very easy to describe what "life" is. It's almost as hard as describing where life came from.

The study of life is called "biology" and the people who study it are "biologists". They even have a tough time describing what life is! But after many years of studying living things, from the mold on your old tuna sandwich to monkeys in the rainforest, biologists have determined that all living things, do share some things in common:

1) Living things need energy
2) Living things grow and develop
3) Living things respond to their surroundings
4) Living things reproduce



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The Spring 2010 issue of The Earth Scientist, focuses on the ocean, including articles on polar research, coral reefs, ocean acidification, and climate. Includes a gorgeous full color poster!

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF