STEM 1203 BIOLOGY.pdf

THE WACKY HISTORY OF CELL THEORY THE WEIRD HISTORY OF THE CELL THEORY 1. All organisms are composed of one or more cells. 2. The cell is the basic unit of structure and organization in organisms. 3. All cells come from preexisting cells. Early 1600s, Netherlands, a spectacle maker named Zacharias J...

THE WACKY HISTORY OF CELL THEORY THE WEIRD HISTORY OF THE CELL THEORY 1. All organisms are composed of one or more cells. 2. The cell is the basic unit of structure and organization in organisms. 3. All cells come from preexisting cells. Early 1600s, Netherlands, a spectacle maker named Zacharias Janssen, said to have come up with the first compound microscope, along with the first telescope. Both claims are disputed as apparently he wasn't the only bored guy with a ton of glass lenses to play with at the time. Despite this, microscopes become the hottest that all scientists want. Anton van Leeuwenhoek, who made his own microscope, looked more like a tiny paddle the size of a sunglass lens. He went to town looking at anything and everything he could with them, including the gunk on his teeth. He discovered bacteria by looking at dental scrapings. He called bacteria animalcules because they look like little animals to him. He sent a letter to a colleague named Robert Hooke, a guy who really loves all aspects of science. As he looked at a piece of cork under his microscope, and the little chambers he saw reminded him of cells, or the room monks slept in their monasteries. So, he called animalcules a cell. Newton and Hooke fight because Newton didn't like what Hooke said that Newton got the idea from him. No one knows what Robert Hooke looks like. In the 1800s, two German scientists discovered the cell theory. Matthias Schleiden, botanist who liked to study plants under a microscope. He realized that all plants he looked at were all made of cells. Theodor Schwann, concluded that all animals were made of cells. Schwann says that cells come from preexisting cells, but Schleiden did not exactly agree on that, he swore cells came from free-cell formation, where they just kind of spontaneously crystallized into existence. Rudolf Virchow stepped in with research showing cells did come from other cells. Research that is borrowed without permission from a jewish scientist by the name of Robert Remak, which led to two more feuding scientists. CELL THEORY AND STRUCTURES WHY STUDY CELL BIOLOGY? The key to every biological problem must finally be sought in the cell, for every living organism is, or at some time has been, a cell. E.B. Wilson, 1925 CELLS ARE US A person contains about 100 trillion cells. That’s 100,000,000,000,000 or 1 x 1014 cells. There are about 200 different cell types in mammals (one of us). Cells are tiny, measuring on average about 0.002 cm (20 um) across. That’s about 1250 cells, “shoulder-to-shoulder” per inch.