Transcript Cell Theory, Prokaryotic or Eukaryotic Cells

Cell Theory
and cell scientists
cell n.
• The smallest unit of any organism that is
capable of independent function.
• It is composed of a small mass of
cytoplasm, that usually encloses a central
nucleus, and is surrounded by a
membrane (and sometimes, a rigid cell
wall)-plants Webster’s Dictionary
Robert Hooke
• In 1665 Robert Hooke observed thin
sections of cork using his simple
microscope.
• He names the small compartments he
viewed, cells.
Hooke did not view living cells but only
saw cell walls without the cytoplasm
and organelles.
Anton van Leuwenhoek
In 1673, Anton van Leuwenhoek used a
handmade microscope to observe pond
water and discovered single-celled
organisms he called animalcules.
Mathias Schleiden
plant cell
Mathias Schleiden: (1838- botanist)
stated that all plants are made up of
cells.
Theodore Schwann
Theodore Schwann (1839-zoologist) stated
that all animals are made up of cells.
Rudolph Virchow
Rudolph Virchow (1859)-stated that all
cells come from other cells.
1) All living things are made up
of one or more cells.
2) Cells are the structural and functional
unit of all living things. (“Basic unit of
life.”)
3) Cells come only from other cells.
Prokaryotic Cells – They are cells that
have a cell membrane and cytoplasm, but
do not contain a nucleus. (bacteria)
These are believed to be the type of cells
that developed first on the Earth.
All bacterial cells are prokaryotic.
Eukaryotic cells
A Eukaryotic cell, unlike a prokaryotic cell,
contains a nucleus and many organelles
(cell structures).
Animal, plant, protist and fungal cells are all
eukaryotic. (The organisms are EUKARYOTES)
Eukaryotic Cell Comparisons