The Development of the
Cell Theory
The Cell Theory States:
• As written by Rudolph Virchow (1821-1902):
– All living organisms are made of one or more cells.
– Cells are the basic units of structure and function in
all organisms.
– All cells come from previously existing cells.
– The activity of an entire organism depends on the
total activity of its independent cells.
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
1600
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Ancient Times
• Ancient peoples were always
on the look-out for ways that
organisms can be used by
them.
• They passed on their
understanding orally.
• Some civilizations supported
“great thinkers” – and
philosophers, but they rarely
based their thoughts on
observation or experiments.
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
1600
1500
334 B.C.E - Aristotle
• Greek philosopher,
Aristotle, began to observe
nature.
• He classified all known
organisms as either a Plant
or and Animal.
• He wrote that living things
can arise spontaneously
from non-living matter.
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1268 – 1st Eyeglasses
• Roger Bacon, an English
friar made reference to a
pair of eye glasses.
• This meant that glass was
being developed and used
in a way that makes it
easier to see small things.
• Physics
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1590 – 1st Microscope
• Zacharias Janssen, a Dutch
eyeglass maker, made the
first microscope by placing
two lenses on top of one
another to make extra-large
images.
• Physics
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1800
1700
1900
1600’s
• People started to suggest that
life can only come from other
forms of life rather than
through spontaneous
generation (as was suggested
by Aristotle).
• William Harvey said that
maggots do not come from
the meat itself but from tiny
eggs too small to be scene.
• Biology/Medicine
William Harvey
English Physician
1578-1657
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1665 – 1st Cells Seen
• Robert Hooke (1635-1703)
published a book with
illustrations of tree bark as
seen through a simple
compound (2 lens)
microscope.
• Physics
William Harvey
English Physician
1578-1657
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1800
1700
1668 – 1st Experiments about origins of maggots
• Francesco Redi (16261697) conducted
experiments to prove
that maggots do not
appear in meat if flies
cannot land on it!
• Biology
William Harvey
English Physician
1578-1657
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1800
1700
1674 – 1st Microscopic Organisms Seen!
• Anton van Leeuwenhoek
(1632-1723) reported being
able to see tiny beasties
(0.002 mm) using a simple
single-lens microscope.
• Biology
William Harvey
English Physician
1578-1657
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1753 – Birth of Classification
• Carolus Linnaeus (17071778) began to show people
the great diversity of living
things by exploring methods
of classifying them into 5
main Kingdoms.
• Biology
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1800
1700
1770 – Advancement of Microscopes
• Microscopes became
sturdier and easier to use.
• Flaws in glass production
still caused images to be
blurry and have coloured
halos.
• Physics
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
1600
1500
1800
1700
1809 – 1st Science Texts for Students
• Jane Haldimand (1769-1858)
wrote textbooks for young
people to learn about
science.
• Words such as “cell”,
“cellular system” and
“Cellular tissue” appear in
the book.
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1820’s – Better Glass = Better Lens
• Microscope quality
improved with the
production of better glass.
• Many English companies
competed to produce the
best microscope.
• Physics
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
1600
1500
1825 – Book “Cells from Cells”
• Francois Vincent
Raspail (1794-1878)
wrote a book called
“Every cell is derived
from a preexisting
cell”.
• Biology
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
1600
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1830 – Cells are studied
• Biology was becoming
an important science
and the body of
knowledge was growing,
especially since the
improvement of
microscopes.
• Scientists began to study
the cell extensively.
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1831 – Nucleus of Cell Found
• Robert Brown (1773-1858)
was the first to think of the
nucleus as a regular part of a
living cell.
• The nucleus was still hard to
see though without the
invention of the electric light
for his microscope.
• Biology
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
1600
1500
1800
1700
1838 – Plant cells!
• Matthias Jacob Schleiden
(1804-1881) made the claim
“All plants are made of cells”.
• Cells are alive!
• Biology
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1839 – Animal cells!
• Theodor Schwann (18101882) made the claim “All
animals are made of cells”.
• Cells are the basic structure
of life!
• Biology
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1845 – Cell Basic Unit of Life
• Alexander Carl Heinrich
Braun (1805-1877) said:
“The cell is the basic unit of
life”.
• Cells are made of protoplasm
enveloped by a flexible
membrane.
• Biology
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
1600
1500
1856 – Staining technique developed
• 18 year old, William
Henry Perkin (18381907) developed a new
purple dye for staining
cell parts making it
easier to see cell parts
with a microscope.
• Chemistry
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1858 – Article on Evolution
• Charles Darwin (1809-1882)
& Alfred Wallace (18231913) read their article on
“Tendency of species to form
variations”.
• Biology
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
300 BCE
1000
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1858 – Cell Theory Outlined
• Rudolph Virchow (18211902) developed his Cell
Theory that is still largely
accepted today.
• Biology
1800
1700
1900
Timeline of the discoveries, thoughts and technologies that led to the development of the Cell Theory
500 BCE
1000
300 BCE
1600
1500
1800
1700
1860’s – The end of the “Spontaneous Generation” debate
• Louis Pasteur (1822-1895)
conducted a series of
experiments that once and
for all put to rest the idea of
spontaneous generation and
concluding that living
organisms do not arise from
non-living matter.
• Biology
1900