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  • Kansas Legislator Proposes Bill to Outlaw Sustainability Education
    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of ...Read more

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    Kansas Legislator Proposes Bill to Outlaw Sustainability Education

    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of sustainability. Here is a link to the one-page bill: http://www.kslegislature.org/li/b2013_14/measures/documents/hb2366_00_0000.pdf. See report on Bloomberg News.
  • Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows
    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 ...Read more

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    Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows

    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 degrees hotter than in a previous experiment run 20 years ago. These measurements confirm geophysical models that the temperature difference between the solid core and the mantle above, must be at least 1500 degrees to explain why the Earth has a magnetic field. For more information about this study, see the press release from the European Synchrotron Radiation Facility.
  • Ocean Volcanic Rocks Contain Samples of Recycled Crust
    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials fr...Read more

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    Ocean Volcanic Rocks Contain Samples of Recycled Crust

    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials from the early Earth’s crust. But decisive evidence for this phenomenon has proven elusive. New research from a team including Carnegie’s Erik Hauri demonstrates that oceanic volcanic rocks contain samples of recycled crust dating back to the Archean era 2.5 billion years ago. Their work is published in Nature. Oceanic crust sinks into the Earth’s mantle at so-called subduction zones, where two plates come together. Much of what happens to the crust during this journey is unknown. Model-dependent studies for how long subducted material can exist in the mantle are uncertain and evidence of very old crust returning to Earth’s surface via upwellings of magma has not been found until now. For more information about these results, see the press release from the Carnegie Institution.
The leaf is the primary site of photosynthesis in plants.
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Image has been released into public domain (found on wikipedia.org).

Photosynthesis

Photosynthesis is the name of the process by which autotrophs (self-feeders) convert water, carbon dioxide, and solar energy into sugars and oxygen.


It is a complex chemical process by which plants and other autotrophs create the energy needed for biological life. The equation above shows the production of CH2O (formaldehyde), only one of the many carbohydrates that actually form.

The oxygen that is a byproduct of the photosynthesis reaction leaves the plant through the stomata (openings between guard cells on the surface of a plant's epidermis that let in carbon dioxide and let out oxygen). This oxygen is essential in supporting life on Earth.

It is estimated that a full-grown, healthy maple tree has about 500 square feet of leaves weighing about 500 pounds. This represents a total chloroplast surface area of about 140 square miles. Believe it or not, a single maple tree can make two tons of sugar on one good sunny day! (The Way Life Works, Hoagland and Dodson) That's a lot of sugar!

Early bacteria converted solar energy by a different photosynthetic reaction, one which requires an anaerobic environment (one without oxygen), but which produces water as a waste product. The photosynthetic activity of this early bacteria was an interim step in building the oxygen content of Earth's early atmosphere.

The reverse process of photosynthesis is known as respiration. Respiration occurs in all organisms.

Last modified February 8, 2011 by Jennifer Bergman.

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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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