Robert Hooke
• 1665 – Micrographia
• First to identify structure known as cells in cork
• Predicted that there are 1,259,712,000 cells in the human body

Anton van Leewenhoek
• 1676 – First to observe live cells
• 1683 – Discovers bacteria

Matthias Schleiden
• 1838- Suggests that all plants are comprised of multiple cells
• Also discovered the importance of the nucleus

Theodor Schwann
• 1839 – Suggests that all animals are made of many cells
• Also coined the term
“metabolism”

The Cell Theory
• 1) All living things are made of at least one cell
• 2) Cells are the basic units of life.
• 3) Cells may develop as a result of spontaneous generation

Rudolf Virchow
• 1855 – Suggests that cells must come from pre-existing cells

The Cell Theory Version 2.0
• 1) All living things are made of at least one cell
• 2) Cells are the basic units of life.
• 3) Cells must develop from pre-existing cells

CYTOLOGY

Cells By The Numbers
• 10,000 Trillion Cells per person (avg.)
• 90%+ are not you
• Hundreds of different cell types made of
100 million proteins. There are 200,000+ different types of these proteins. We know the exact form of 2% of these proteins
• Electrical activity of 0.1 volts/nanometer = same as a thunderstorm
• DNA attacked every 8.4 seconds

Cellular Unity & Diversity: How and Why?

Lab: Fundamentals of Light
Microscopy
• Purpose: To develop facility with using the compound light microscope and to prepare specimens for viewing
• Methodology: Light microscopy

Watch Your Cords!

Part 2: Calculating Magnification
• Ocular = 10x
• Objective = 4, 10 or 43x
• Total Magnification = ocular x objective

Part 2: Measuring Field of View

Approximating Cell Size
• To calculate approximate cell size, estimate how many cells lined end to end would cover the diameter of the field of view.
• Divide the field size by this estimated number of cells = appx. cell size (in um)

After centering, adjust light before attempting to focus

Part 4: Depth of Field

PART 5: Wet Mount Slide