Cell Theory the CELL THEORY GREW out of the WORK of MANY SCIENTISTS and IMPROVEMENTS in the MICROSCOPE
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Cell Theory THE CELL THEORY GREW OUT OF THE WORK OF MANY SCIENTISTS AND IMPROVEMENTS IN THE MICROSCOPE. Many scientists contributed to the cell theory. ROBERT HOOKE He was the first person to look at cells and named them. He looked at cork cells which are not living. It is the bark of a tree so they are dead plant cells. They are small squares and they reminded him of the small rooms in a monastery called cells ANTON VAN LEEUWENHOEK Credited with improving the microscope. (Zacharias Janssen is credited with discovering/creating microscope). Leeuwenhoek’s microscope could magnify 200x the human eye! Today’s microscopes can magnify up to 1500! MATTHIAS SCHLEIDEN was a German botanist (scientist who studies plants.) He found that the plant parts he examined were made of cells. He made the generalization that all plants were made of cells. THEODOR SCHWANN Studied animals. His microscopic investigations of animal parts led him to generalize that all animals are made of cells After looking at Schleiden’s work ,he further proposed that all organisms are made of cells. RUDOLF VIRCHOW- OMNIS CELLULA C CELLULA”: ALL CELLS FROM CELLS (1855) German doctor that said that new plant cells arise only from existing plant cells, and new animal cells arise only from existing animal cells. Building off the work of Redi (1668) who disproved the idea of spontaneous generation in his experiments about rotting meat. LOUIS PASTEUR-GERM THEORY 1856-Used the microscope to discover that tiny, one- celled (eukaryotic) yeast created alcoholic fermentation and that other one-celled, rod-shaped organisms (prokaryotic bacteria) caused beverages to spoil. Pasteur (1864) designed a flask experiment that disproved the idea of spontaneous generation once and for all! Ask me why I don’t have anthrax! images from “amoeba Mike” and Britannica Early studies led to the development of the cell theory. The Cell theory has three principles. 1) All organisms are made of cells. Early studies led to the development of the cell theory. The Cell theory has three principles. 1) All organisms are made of cells. 2) All existing cells are produced by other living cells. Early studies led to the development of the cell theory. The Cell theory has three principles. 1) All organisms are made of cells. 2) All existing cells are produced by other living cells. 3) The cell is the most basic unit of life. There are two cell types: eukaryotic cells and prokaryotic cells: Comparing cell types There are two cell types: eukaryotic cells and prokaryotic cells. Eukaryotic cells have a nucleus (true nucleus)which contains DNA that forms many chromosomes. nucleus cell membrane There are two cell types: eukaryotic cells and prokaryotic cells. Eukaryotic cells have a nucleus. Eukaryotic cells have membrane-bound nucleus organelles. organelles cell membrane There are two cell types: eukaryotic cells and prokaryotic cells. Prokaryotic cells do not have a nucleus. Prokaryotic cells do not nucleus have membrane-bound organelles, but they do have some organelles like ribosomes. organelles cell membrane cytoplasm There are two cell types: eukaryotic cells and prokaryotic cells. Prokaryotic cells do not have a nucleus, but they have one chromosome and “extra” circular pieces of DNA called “plasmids”. Draw a circular plasmid in your bottom cell diagram on your notes and label it “plasmid DNA”. EUKARYOTIC CELLS VS PROKARYOTIC BACTERIA CELLS Nucleus Organelles Eukaryotic DNA/Chromatin Cytoplasm Cell membrane Prokaryotic DNA/Chromatin Plasmid DNA Cytoplasm Cell membrane .