Cell Theory
description
Transcript of Cell Theory
Cell Theoryand cell scientists
• 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
cell n.
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 ahandmade microscope to observe pond water and discovered single-celledorganisms 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