The Cell Theory – a timeline

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Transcript The Cell Theory – a timeline

The Cell Theory – a timeline
• Late 1500’s:
• Early 1600’s:
-first lenses used in Europe
-used to determine cloth
quality (weave and
precision)
-combos of lenses gave better
view
Leeuwenhoek uses
microscope to study nature
Early
1600’s
Early 1600’s
• Leeuwenhoek
• first to view pond
water organisms
• First to see living
microscopic orgs
• Made careful
sketches
Robert Hooke ( 1665)
• Used light
microscope to look at
thin slices of plant
tissues -- cork
• Looked empty, like
monk’s chamber
• Called tiny chambers
“cells”
Matthias Schleiden 1838
• German Botanist
(plants)
• All plants looked at
were made of cells,
so concluded:
“All plants are
made of
cells.”
Theodore Schwann -- 1839
• German scientist
who studied animals
-- zoologist
• Saw that all animals
he studied were
cellular so
concluded:
“All animals are
made of cells.”
Rudolf Virchow -- 1855
• German physician
who studied cell
reproduction
• “Where a
cell exists,
there must
have been a
preexisting
cell…..”
The Cell Theory
1. All living things are composed of
cells
2. Cells are the basic units of structure
and function in living things
3. New cells are produced from
existing cells
Prokaryotes vs. Eukaryotes
• Prokaryotes:
• Eukaryotes:
*NO NUCLEUS
*Small and Simple – few
organelles
*Have cell membranes
and cytoplasm
Ex. Bacteria
*Contain nucleus
*Contains organelles that
perform specialized
functions
*Uni-or multicellular
Figure 7.4 A prokaryotic cell
Eukaryote Cell