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Biology 3A
Biology 3A

... Watching T.V. D Sleeping 12. Where do plants get the glucose that they use for respiration? A From nutrients in the soil B From osmosis of water C From photosynthesis D From respiration 13. When might your body experience an oxygen debt? A After waking up in the morning B After going for a long walk ...
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... (1635–1703), one of the first scientists to use a microscope to examine pond water, cork and other things, was the first to refer to the cavities he saw in cork as ‘cells’, Latin for chambers. Subsequent scientists developed Hooke’s discovery of the cell into the Cell Theory on which modern Biology ...
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tissues - Linn-Benton Community College
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... humans.) Pathogenic Bacteria (Disease causing) A. These prokaryotes account for more than half of all non- genetic diseases in humans. B. Opportunists (such as streptococcus) become a problem when the body is busy fighting something else, such as a cold virus. (They see an opportunity to reproduce a ...
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Cell theory



In biology, cell theory is a scientific theory which describes the properties of cells. These cells are the basic unit of structure in all organisms and also the basic unit of reproduction. With continual improvements made to microscopes over time, magnification technology advanced enough to discover cells in the 17th century. This discovery is largely attributed to Robert Hooke, and began the scientific study of cells, also known as cell biology. Over a century later, many debates about cells began amongst scientists. Most of these debates involved the nature of cellular regeneration, and the idea of cells as a fundamental unit of life. Cell theory was eventually formulated in 1838. This is usually credited to Matthias Schleiden and Theodor Schwann. However, many other scientists like Rudolf Virchow contributed to the theory. Cell theory has become the foundation of biology and is the most widely accepted explanation of the function of cells.The three tenets to the cell theory are as described below: All living organisms are composed of one or more cells. The cell is the most basic unit of life. All cells arise from pre-existing, living cells, by biogenesis.
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