CONTRIBUTIONS TO
THE CELL THEORY
Timeline of scientists
and their discoveries
Anton van
leeuwenhoek
1600’s
Dutch
businessman
Observed tiny
organisms in
pond water
using a simple
light
microscope
Anton van
leeuwenhoek
Microscopic
organisms
from the
pond water
were
nicknamed
“wee beasties”
ROBERT HOOKE
1665
English
physicist
Observed
flowers,
insects, and
plant tissue
ROBERT HOOKE
Observed thin
slices of cork
(oak tree)
Coined the
term “cell”
based on the
rooms in a
monastary
ROBERT BROWN
1833
Observed
plant cells
under the
microscope
ROBERT BROWN
Observed a
dark
structure
inside each
cell and
coined the
term
“nucleus”
MATTHIAS SCHLEIDEN
1838
German
botanist:
scientist who
studies plants
Concluded
all plants are
made up of
cells
THEODORE SCHWANN
1839
German
biologist
Concluded
all animals
are made of
cells
RUDOLF VIRCHOW
1855
German
Physician
Studied cell
reproduction
Concluded
all cells arise
from
preexisting
cells
The cell theory
1. All living things are
composed of cells
2. Cells are the basic unit of
structure and function in
living things.
3. All cells arise from
preexisting cells.