1. Cell Theory and Microscopes
Bio.1.1 Understanding the relationship between the structures and functions of cells and their organelles.

2. Discovery of the Cell
Robert Hooke (1665) used compound light microscope to examine a cork
The porous boxes he observed he named “cells”
Anton van Leeuwenhoek (1673) – used simple light microscope to view living cells (microorganisms, blood, etc.)

3. Cell Theory Early 1800s – Cell theory = unified theory stating:
All living things are composed of cells
Cells are basic units of structure and function
Cells come from existing cells

4. Evidence of Cell Theory
Matthias Schleiden (1838) – confirms all plants made up of cells
Theodor Schwann (1839) – confirms all animals made up of cells
Rudolf Virchow (1855) – discovers cells only come from other cells

5. Microscopes Used to study cells by enlarging the image of an object
Stage
Objective Lens
Nosepiece
Eyepiece
Stage clips
Base
Arm
Course Adjustment Knob
Fine Adjustment knob
Condenser

6. Microscopes
Compound Light Microscope (LM) – used to examine small organisms and cell
1500 x magnification
Can observe nuclear division

7. Compound Light Microscope
Computing the Power of Magnification:
ocular lens (eyepiece) x objective lens
Ocular lens = 10x magnification
What is the total magnification of an organism viewed at 40 x objective lens?

8. Microscopes
Transmission Electron Microscope (TEM) – transmits beam of electrons
200,000 x magnification
Can view more organelles
Scanning Electron Microscope (SEM) – bounces electrons off of object producing 3D image
100,000 x magnification

9. Microscopes
Scanning Tunneling Microscope (STM) – views images at atomic level