Transcript Cell Notes. Chapter 4

Cell Notes. Chapter 4
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Historical Discoveries
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A) Hooke: A watchmaker who decided
to try his skills at making a microscope.
(Image at right on notes page.)
Hooke was the first person to use the
term “CELL” because what he was
seeing looked like the rooms of a
monastery, which were called cells at
that time.
Historical discoveries
(Continued)
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B) Leeuwenhoek: Improved Hooke’s
microscope. He produced some scopes that
were able to magnify images up to 500X.
First to see: Protista, bacteria, spermatazoa.
He presented Peter the Great with an “eel
viewer” so that he could observe blood
circulation in the eel.
Cell Theory:Schleiden,
Schwann and Virchow
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1) All cells come from pre-existing
cells.
2) Cells are the smallest unit of living
organisms. (Cells are the basic units of
life)
3) All living organisms are made up of
one or more cells.
Shape –vs- Function
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All cells have unique shapes which are
not random, but instead serve specific
functions.
Altering the shape of a cell can alter its
ability to function well.
Ex: Why must blood cells take their
shape?
Why must neurons have their shape?
Why must blood cells take
their shape? Neurons?
Endosymbiotic Theory
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The endosymbiotic Theory concerns the
mitochondria, plastids, (Chloroplasts) and
possibly other organelles of eukaryotic cells.
According to this theory, certain organelles
originated as free-living bacteria that were
taken inside another cells as endosymbionts.
Mitochondria developed from proteobacteria
and chloroplasts from cyanobacteria.
Endosymbiosis
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Prokaryotes vs Eukaryotes
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Prokaryotes
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Single cells only
Limited parts (ribosome, cell
membrane, cell wall)
No specific compartments to perform
key metabolic functions
Oldest cells on the earth
Example: Bacteria
Eukaryotes
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Single AND multicellular
Multiple organelles
Organelles serve as compartments for
specific metabolic functions
Younger cells
Ex: Plant and animal cells, protista
FYI
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Kingdom Protista