For a long time the circulatory system presented an large(p) puzzle. People could observe arteries and veins, and see that these blood vessels branched onward into smaller and thinner vessels. Some observers speculated that blood from the arteries returned to the heart with veins. However, they had had no means to investigate this. They had reached the limits of human sight. The invention of the aesthesis lens microscope by Leeuwenhoek, who was the first to observe unicellular organisms, abrasive 1668 allowed scientists for the first time to view the most basic dowry of life, the cell. Antony van Leeuwenhoek was an unlikely scientist, born in 1632 into a family of tradesmen in Delft, Holland. He had no fortune, no university education, and knew only(prenominal) his native language, Dutch. His function of any formal qualifications or wealth would seem to lick great odds against him for success in the scientific fit of his time. However Leeuwenhoeks determination an d curiosity allowed him to succeed in fashioning important discoveries in the field of biology. Leeuwenhoek is best known for his improvement of the microscope. As a hobby Leeuwenhoek ground lenses and used them to find out tiny objects. Using these lenses, he observed protozoa in pond water and bacteria in the human bank and intestine. He gave the first full descriptions of bacteria, protozoan, and spermatozoa.
The lenses allowed him to discover blood corpuscles and capillaries, and likewise to describe the structure of muscles and nerves. His observations laid the foundations for bacteriology and protozo ology. In 1595, nearly twoscore geezerhoo! d prior to Leeuwenhoeks birth, compound microscopes had been invented in England by Robert Hooke and in the Netherlands by Jan Swammerdam. These compound microscopes were similar to the ones in use straightaway tho only increased the magn/;ification power by only 20x. Leeuwenhoeks delight in... If you want to get a full essay, revise it on our website: OrderCustomPaper.com
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