The Cell and Cell Theory

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The Cell and Cell Theory
Robert Hooke Louis Pasteur
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History
In the early 1600s, around the same time as the
pilgrims were coming to America, the art of
glassmaking was greatly improving. By the middle
of the 1600s a new invention called the
microscope was created using two glass lenses and
a light.
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Robert Hooke looks at a piece of cork
In 1665 Robert Hooke used a microscope to look at
a thin slice of cork. This is what he saw. What
does it look like to you?
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What are those little rooms?
To Robert Hooke those little boxes looked like
tiny rooms. He called these tiny rooms Cells.
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Where else can we find cells?
If you were Robert Hookes assistant, where would
you tell him to look next?
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He looked at other trees bark. Guess what he
found.
He found Cells
He looked at leaves. Guess what he found.
He found Cells
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He looked at his hairHe looked at his
skinHe looked at a rock
He found Cells
He found Cells
He did not find Cells
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He looked at some metalHe looked at some
waterHe looked at a cats bloodHe looked at
a piece of wood...
He did not find Cells
He did not find Cells
He found Cells
He found Cells
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Why did he find cells in some places but not in
others?
1. All living things have cells.
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Not only do all living things have cells, but
they are made of cells.
Whats the difference?
You all have a nose but are you made of noses?
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2. The cell is the smallest living thing that
can perform all the functions of life.

1. It grows, develops, and dies
2. Uses energy
3. Needs water
4. Responds to changes in its environment
5. Gives off waste
6. Reproduces

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Science Headline NewsYear 1850
Scientists prove that Maggots come from dead meat
Dr. Scientist proved that maggots come from dead
meat. After leaving meat out in his laboratory
Dr. Scientist noticed that small maggots were
found crawling out of the meat. Dr. Scientist
said this proves maggots come from meat.
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Do you believe that maggots come from meat?
Louis Pasteur did not believe this. How could he
prove Dr. Scientist wrong?
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Pasteurs experiment
Pasteur covered up some meat and left it out. Do
you think maggots would be found inside his meat?
No.
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Pasteur concluded that flys were landing on the
meat and laying eggs on the meat. When the eggs
hatched the maggots came out.
3. Cells come from other cells from the same
species.
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Summary