CELL HISTORY

1
CELL HISTORY

• ROBERT HOOKE (England)
• 1665 observes slice of cork (bark from oak tree)
  with a 30X microscope
• Noticed tiny boxes in cork
• Called them CELLS

2
CELL HISTORY

• ANTON VAN LEEUWENHOEK (Netherlands)
• Creates a microscope from polished sand- 300 X
• Observes clear pond water
• Notices a world of tiny organisms- called them
  ANIMALCULES (actually single celled protists)
• First to see living cells- 1675

3
CELL HISTORY

• MATTHIAS SCHLEIDEN THEODORE SCHWANN (Germany
  1839)
• SCHLEIDEN- plants made of cells
• SCHWANN- animals made of cells
• Put it all together
• Every living thing is composed of cells

4
CELL HISTORY

• RUDOLPH VIRCHOW- Germany 1855
• Observed that cells come from other cells

5
THE CELL THEORY

• All of this information led to the CELL THEORY
• 1) All living things are composed of one or more
  cells
• 2) Cells are the basic units of structure and
  function of organisms
• 3) Cells come from the reproduction of existing
  cells

6
CELL SIZE

• Are elephant cells larger than ant cells?

7
NO

• the small size allows materials to reach all cell
  parts
• the surface area
• of the cell must be
• able to supply raw
• materials
• volume will increase
• faster than surface area

8
Surface area Volume

• Surface area is area on surface of object- area
  of all sides
• Volume is amount of space in an object
• Cells want to maximize this ratio
• Have a large enough surface area while keeping
  volume small