The greeks believed the Earth was stationary at the center of the universe while objects in the sky revolved around it. The Greek astronomers employed the term Asteres planetai meaning “wondering stars” for star like objects. By the 19th century the word planet thought it hadn’t been defined was the working term applied
Releasing insulin to decrease blood sugar and releasing glucagon to increase blood sugar
Botanist
Biologist/Biological Scientist: A scientist who studies living organisms and living systems. Botanist: A scientist who studies plants. Chemical Ecologist: A scientist who studies chemicals in the interactions of living organisms. Chief Scientist: A scientist who leads other scientists in a particular research area.
arbon, as with many elements, can arrange its atoms into several different geometries, or "allotropes." In pure diamond, every carbon atom is covalently bonded to exactly 4 other carbon atoms in a very specific and energetically favorable geometry. The diamond cannot be broken or scratched unless many covalent bonds are broken, which is difficult to do. In another common allotrope, graphite, every carbon atom is covalently bonded to only 3 other carbon atoms, and the atoms are arranged in sheets that are not covalently bonded to each other. The sheets can be broken apart easily, ultimately meaning that graphite can be easily scratched. Coal is composed of particles of different allotropes of carbon, and some "amorphous carbon," which has no defined geometry in its atomic structure. Without a continuous network of covalent bonds, coal is easily scratched (i.e. it is not hard).
Rose bush because not many animals eat rose bushes