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Our Galactic Neighbor Is Up To 40,000 Light-Years Closer To Us Than We Thought

07/03/2013 06:09
Robert Ferris | Mar. 6, 2013, 3:10 PM Using high-powered telescopes and a sophisticated system of measurement, scientists know the distance of a neighboring galaxy more accurately than ever before. The study measured the Large Magellanic Cloud, on of our closest galactic neighbors, to be...

Which Elements Are Named After People?

07/03/2013 05:00
By Anne Marie Helmenstine, Ph.D., About.com Guide There are 13 elements named after people, although only 12 of the names are formally accepted by the International Union of Pure and Applied Chemistry (IUPAC). bohrium (Bh, 107) – Niels Bohr curium (Cm, 96) – Pierre and Marie Curie einsteinium...

What Is a Chemical Element?

07/03/2013 04:57
By Anne Marie Helmenstine, Ph.D., About.com Guide A chemical element, or an element, is a material which cannot be broken down or changed into another substance using chemical means. Elements may be thought of as the basic chemical building blocks of matter. Depending on how much evidence you...

Chemical Composition of the Human Body

07/03/2013 04:48
By Anne Marie Helmenstine, Ph.D., About.com Guide   This is the elemental chemical composition of the average adult human body. Water is the most abundant chemical compound in living human cells, accounting for 65-90% of each cell. Each water molecule consists of two hydrogen atoms bonded to...

How Many Atoms Are There in a Human Cell?

07/03/2013 04:45
By Anne Marie Helmenstine, Ph.D., About.com Guide Have you ever wondered how many atoms are in a human cell? It's a huge number, so there is no exact figure, plus cells are different sizes and are growing and dividing all the time. Here's a look at the answer. [Read more] ...

How Many Atoms Are in the Human Body?

07/03/2013 04:43
By Anne Marie Helmenstine, Ph.D., About.com Guide   Have you ever wondered how many atoms are in the human body? Here's the calculation and answer to the question. There are approximately 7 x 1027 atoms in the average human body. This is the estimate for a 70 kg adult human male. Generally, a...

Loss of wild insects hurts crops around the world

06/03/2013 09:48
by Staff Writers Calgary, Canada (SPX) Mar 06, 2013 Researchers studying data from 600 fields in 20 countries have found that managed honey bees are not as successful at pollinating crops as wild insects, primarily wild bees, suggesting the continuing loss of wild insects in many agricultural...

After the human genome project: The human microbiome project

06/03/2013 09:45
by Staff Writers Bethesda MD (SPX) Mar 06, 2013 Earth Day may be more than a month away, but another, more personal, ecosystem has been shown to also be worth protecting-within our bodies are communities of microbes that affect the behavior of human cells hosting them. These communities, called...

Molecules Assemble in Water, Hint at Origins of Life

06/03/2013 07:23
The base pairs that hold together two pieces of RNA, the older cousin of DNA, are some of the most important molecular interactions in living cells. Many scientists believe that these base pairs were part of life from the very beginning and that RNA was one of the first polymers of life. But there...

Secret Life of Bees Now a Little Less Secret

06/03/2013 07:18
Many plants produce toxic chemicals to protect themselves against plant-eating animals, and many flowering plants have evolved flower structures that prevent pollinators such as bees from taking too much pollen. Now ecologists have produced experimental evidence that flowering plants might also use...
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