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Linné on line arrow Physics and the Cosmos arrow Microcosmos – the structure of matter

Microcosmos – the structure of matter

For a long time man has wondered what things consist of. Take a flower for example. With the help of our eyes we can study how the flower looks. But what does it really consist of? For a long time it was believed that everything consists of four different substances or elements as the Greek philosopher Aristotle called them. Do you know what these four elements where? The answer, together with some more information about how the ancient Greek philosophers viewed the world, you can find here.

Levande materia Kondenserad materia Atomer Atomkärna  Kvarkar och Leptoner   When Linnaeus studied the plants he used his own eyes to see the details, such as the number of stamens and pistils, but if we want to see even smaller details, then the human eye is not sufficient. Instead we have to use different types of instruments. If we take a part of the flower and study it in a microscope then we can see that it consists of cells with nuclei. In the nucleus of a cell the genetic information is stored in the genetic code, DNA, a long chain of molecules. The molecules in turn are built from atoms that also have nuclei surrounded by clouds of electrons. As far as we know today the electrons have no inner structure, instead they are pointlike. The atomic nucleus on the other hand has a rich substructure. It consists of protons and neutrons which in turn are built from quarks. To be able to study the smallest constituents of matter one needs accelerators that are tens of kilometers long and complicated detectors that are about the same size as an ordinary house. If you want to, you can find your own way to explore the microcosmos by pressing one of the circles on the picture to the left or following one of the links below:
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