Cell Theory. History and Developmentpptx

Cells

1. Cell Theory Cell Unit: Day 1

2. What is a scientific theory?

3. Robert Hooke English scientist 1635-1703 Discovered cells in cork Named cells-cells

4. Anton van Leeuwenhoek Dutch Scientist (1632-1723) Built microscopes First person to see living cells

5. Other scientists to contribute to cell theory: Matthias Schleiden (1838) Concluded that all plants are composed of cells. Theodor Schwann (1839) Concluded that all animals are composed of cells. Rudolf Virchow (1855) Concluded that cells only come from other cells.

6. Cell Theory: All living organisms are composed of one or more cells Cells are the basic units of structure and function in an organism Cells come from other living cells

7. What technology has allowed us to understand cells? Before microscopes we were not aware of microorganisms such and unicellular protists and bacteria. As we have improved microscopes we can see greater detail in the cells. DNA analysis techniques have also helped us learn more about cells, this helps us understand how different organisms are related. Other chemical analysis of proteins, RNA, etc have also helped us gain an even deeper understanding of cells.

8. Prokaryotic vs. Eukaryotic Cells Prokaryotic Cell Eukaryotic Cell No Nucleus/ DNA in cytoplasm Nucleus/ DNA in nucleus No membrane bound organelles Membrane bound organelles Usually smaller than Eukaryotic cells Usually bigger than prokaryotic cells Evolved 3.5 billion years ago Evolved 1.5 billion years ago Archaebacteria and Eubacteria Fungi, Protist, Plant, and Animal

9. Cell Examples

10. Eukaryotic Cells

11. Prokaryotic Cells