CELL THEORY – all living org = cells Zacharias Janssen 1590s Holland 1 magnifying glass = good Bigger but blurry Not seen until 1600s 2 = better ! ! !
Anton Van Leeuwenhoek Holland mid 1600s BEAD of glass = focuses picture = clear 1 st person to SEE microrg Got to 270X magnification
Robert Hooke British 1665 Put 2 beads in a row Cut up cork – said looked like little jail CELLS
Schleiden 1838 Germany Schwann 1839 Germany Virchow 1854 Russia All plants made of cells All animals made of cells New cells come from old cells
All of that work proved: THE CELL THEORY: 1. All living things are made of cells 2. Cells are the lowest level of structure and function of living things 3.Living cells come from other living cells = theory of BIOGENESIS
Simple light microscope: Bead bends light need straight line thru Mag = amt of bead, ex 10X = 10 timeslight object bead focus
Compound (cmpd) light microscope: 2000X + CLEAR!!! Total mag = bead X beadlight object bead
Must have T H I N object Need light to go THROUGH the object If object = transparent Need to STAIN to see Permanent mount to keep in place
ELECTRON microscope Passes e- through object TEM = transmission e- micro Thin slices in vacuum SEM = scanning e- micro Surface of whole objects