I. Why Study Cells? • Body is made up of cells: • RBC • Nerve Cells • Skin Cells • Muscle Cells
B. Some more examples • White Blood Cells • T Cells & B Cells • Reproductive Cells • Stem Cells
C. Certain Cells can make us sick • Bacterial Cells • Cancer Cells • Protists
II. History of Cell Biology • Zacharias Janssen • 1595 – invented 1st optical compound microscope
2. Robert Hooke • 1665 – used a light microscope to look at non-living cork cells
3. Anton van Leeuwenhoek • Made microscopes with magnification 10x greater • Observed living cells
IV. Cell Theory • 150 years later….(early 1800’s) • Three German scientists developed a theory about cells from their observations.
CELL THEORY • 1.) All living organisms are composed of one or more cells • 2.) Cells are the basic units of structure and function in an organism. • 3.) Cells come only from the reproduction of existing cells.
B. STEREOMICROSCOPE • Gives 3D images ofspecimen
C. SCANNING ELECTRON MICROSCOPE (SEM) • Uses electrons instead of light to project surface image of specimen
D. TRANSMISSION ELECTRON MICROSCOPE (TEM) • Works like light microscope except uses electrons
Electron Microscopes • Can magnify up to 200,000 x