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Cell Lecture #1. What Are Cells? History of Cells. What is a Cell?. A cell is the basic unit of structure and function in living things. Invention of microscope made seeing cells possible. History of Cell Discovery.
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Cell Lecture #1 What Are Cells? History of Cells
What is a Cell? • A cell is the basic unit of structure and function in living things. • Invention of microscope made seeing cells possible
History of Cell Discovery Robert Hooke gets credit for discovering cells by looking at cork - he thought they looked like “prison cells”
Anton van Leeuwenhoek • This Dutch scientist discovered little things swimming in pond water which he called “animalcules” (little animals) with microscopes he made himself
Three parts to the Cell Theory • 1. All living things are made of cells • 2. All cells come from other cells • 3. The cell is the basic unit of structure and function in living things
Early Cell Scientists • 1. Matthias Schleiden discovered that all plants were made of cells in 1835 • 2. Theodore Schwann discovered that all animals were made of cells in 1836
Early Cell Scientists (cont) • 3. Rudy Virchow discovered that all cells come from other cells in 1855;His rule - Omnis cellula e cellula ("every cell originates from another cell")
Main Types of Microscopes • Light microscopes bend light rays through convex lenses. They are powerful because you multiply the powers of each lens to get total magnification
Electron Microscopes • Electron Microscopes use a focused beam of electrons instead of light allowing for much increased magnification. Unfortunately it kills the specimen if it is alive.