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Biology - An overview of NSF research
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Photo, caption follows:

This snapshot comes from an animated simulation of the molecular dynamics of an A. pernix protoglobin model developed at the Maui High Performance Computing Center.
Credit: Image and simulation by James Newhouse, MHPCC

Cover Page Credit: © Merlin D. Tuttle, Bat Conservation International

What is this thing called life?

A bat, a mushroom, a long blade of prairie grass. They're easy to identify as "life." What about a cold virus? Mold growing on a slice of bread? Or seeds encased in hard protective "shells" that can lie dormant for centuries? What, in essence, is this thing we call life?

Some two billion years ago, tiny single-celled organisms, Earth's first life forms, did something amazing. In a world where there was no oxygen, these "micro" organisms began changing the composition of gases in the atmosphere. They added oxygen, making the planet habitable for plants and animals, ultimately creating the living world we see today.

What were the first life forms to use oxygen? NSF-funded scientists recently discovered two oxygen-carrying proteins present in descendents of these early microbes. The proteins are the ancestors to our hemoglobin, which ferries oxygen throughout our bodies. To life on primordial Earth, however, oxygen was poison.

In early single-celled organisms, special proteins arose that captured and transported oxygen, not for use in breathing, but to "detoxify" it so they could live. Eventually, microbes came along that put oxygen to good use. Biologists believe that this transition in the use of oxygen was as important to life as later adaptations from the sea to land, from the ground to the air and from walking on "all fours" to standing upright.

Since that time eons-ago, microbes, plants and animals have colonized Earth's seas and lands, adapting to changing environments along the way. The presence of life has so influenced the nature of our planet, that Earth as we now know it is a result of the countless intricate interactions between its living and non-living components.

NSF's Biological Sciences Directorate funds scientists who conduct research on all aspects of life. Researchers study everything from microbes to rainforests, and the processes that drive life--from cells to ecosystems--to understand what life is, how it works and how and why it changes.

Life on Earth has an active internal chemistry; materials dissolved in water are changed through biochemical reactions in cells into the fuel and raw materials that organisms need to remain alive, grow and reproduce. Cells are life's factories, powerhouses and libraries. They make up living organisms, from the single-celled bacteria to the trillions of cells in a blue whale.

To fuel the chemical reactions that go on in cells, organisms take in and expend energy. Organisms also reproduce. Using the instructions encoded in their cells' DNA, organisms make more of their own kind, assuring the future of life on Earth. Some non-living things--like crystals--"grow" but do not have the features necessary for life.

Biologists like those funded by NSF's Directorate for Biological Sciences are teasing apart how life transmits its qualities from ancestors to descendants. These scientists are studying genes--the signal-operators of the functions of
life--and genomes, the overall pattern of genes in an organism.

Our new century is the heyday of genomics. Once scientists know the sequence of an organism's DNA--its specific arrangement of chemicals--they can identify its genes. Further studies can then shed light on the function of those genes, how they're regulated and what part proteins play in complicated life processes like growth.

Organisms don't remain the same forever. Without change, life on Earth would stagnate. Species are in a constant dance with their environment. When an environment changes, the species that live within must change too--evolving to better adapt--in order to survive. The end result is the diversity of life we see around us.

Recent changes in climate, for example--likely caused by the effects of human activities--are forcing many animals and plants to "step quickly" to keep up. As Earth's northern climates warm, formerly southern animals and plants are moving northward. Individuals better adapted to their environment are more likely to survive and successfully have young. At the same time, life today, like the earliest microbes billions of years ago, continues to change Earth's physical environment.  Our understanding of how these changes occur is still in its infancy.

Biologists are life's detectives, discovering how life works and what makes animals, plants and microbes "alive."

They are asking such questions as:

row bullet How do viruses attack cells?
row bullet How will technology open new doors in biology?
row bullet How can the mustard plant help us understand animals?
row bullet How will studies of neuroanatomy help us understand life-forms as different as dinosaurs and humans?
row bullet What connects fish and maple trees?