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Introduccion Al Microscopio


Enviado por   •  9 de Septiembre de 2013  •  382 Palabras (2 Páginas)  •  450 Visitas

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One of the most important things that zoologists do is observe. Quietly, and unobtrusively, people who study animals must observe what they do, hopefully without interfering with their normal behavior. This is not all that easy to do, even with large animals, but imagine what zoological studies were like when the researchers involved could not see how single and multicellular animals were constructed. The ability to observe cellular and sub-cellular structure changed much earlier than you think, and like most good science, it was a bit of a mistake.

In the 14th to the 17th centuries (the “Renaissance Period”), there were lots of astrologers (like Galileo) scanning the heavens looking at stars and naming planets through the use of telescopes. Consequently, and not surprisingly, it was the conversion of a telescope to what might be called a refracting telescope that gave rise to what we now call the light or compound microscope, Anton van Leeuwenhoek, a Dutchman, is considered the father of microscopy and was first to see single-celled animals, bacteria and yeast with the microscopes he developed. His were simple (one-lens) microscopes. Around the same time i.e., mid 17th century, the English father of microscopy, Robert Hooke, improved on Leeuwenhoek’s designs and is credited with developing the microscope to a point where we could look at sub-microscopic structures including cells. In fact, it was Hooke who first penned the biological term “cell”, taking it from the word used for monks rooms, which were called “cellula”.

In today’s scientific world we have taken things much farther. While the ‘compound microscope’ allows us to see within cells and look at some of the larger organelles (i.e. nuclei and mitochondria) and structures (i.e. chromosomes) it has its limitations. In order to look at much smaller structures scientists had to develop more complex microscopes that have their own high intensity light sources and that revolve around complex vacuum and ionization systems. These include the “electron microscope” (EM) and the “scanning electron microscope” (SEM).

Technology has advanced even further and if your doctor or surgeon want to look at your body’s internal structure and function, they may use either magnetic resonance imaging (an MRI scan) or computed tomography (a CT scan) which creates 3-D images of your internal structure.

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