Cell Theory

Date ?? Aristotle

399 BCE

Articulated principales of generation to account for the theory that developing organisms go through a series of stages before acqiuring their final form - later called Epigenesis
https://embryo.asu.edu/pages/aristotle-384-322-bce#:~:text=Through%20his%20study%20of%20chick,a%20theory%20later%20called%20epigenesis.

1590 - Zacharias Jansen

1590

Made the first Compound Optical Microscope which made it easier and more practical while observing cells. https://www.sutori.com/story/our-cell-theory-timeline--ysqPf9CgJguMXPyQDfDXsv2g#:~:text=Hans%20and%20Zacharias%20Janssen%20are,more%20practical%20whilst%20observing%20cells.

1600 - Jan Baptist Van Helmont

1600

He made an important contribution to photosynthesis.
https://prezi.com/2jgbwwgjdehc/cell-theory-and-discovery-of-the-microscope/#:~:text=Jean%20Baptiste%20van%20Helmont%20contributed,important%20early%20contribution%20to%20photosynthesis.&text=This%20helped%20him%20to%20prove,soil%20was%20a%20wrong%20statement.

1600 - Robert Hooke

1600

Discovered plant cells - first cells from an organsim(cork) were observed by him
https://bio.libretexts.org/Bookshelves/Human_Biology/Book%3A_Human_Biology_(Wakim_and_Grewal)/05%3A_Cells/5.02%3A_Discovery_of_Cells_and_Cell_Theory

1678 - Anton Van Leeuwenhoek

1678

He reported that he observed little animals through a microscope.
https://en.wikipedia.org/wiki/Cell_theory#:~:text=Anton%20van%20Leeuwenhoek%20is%20another,300%2Dfold%2C%20or%20270x.&text=Leeuwenhoek%20named%20these%20%E2%80%9Canimalcules%2C%E2%80%9D,other%20unicellular%20organisms%2C%20like%20bacteria.

1805 - Lorenz Oken

1805

Made the first statement of a cell theory
http://fig.cox.miami.edu/~cmallery/150/unity/cell.text.htm#:~:text=German%20natur%2Dphilosopher%20and%20microscopist,in%20medicine%20at%20Freiburg%20University.&text=It%20is%20reported%20that%20in,statement%20of%20a%20cell%20theory.

1831 - Robert Brown

1831

Discovered the Nucleus which helped confirm the second half of the cell theory.
https://study.com/academy/lesson/robert-brown-cell-theory-inventions-discoveries.html#:~:text=Brown%20published%20his%20research%20findings,half%20of%20the%20cell%20theory.

1838 - Matthias Schleiden

1838

Cofounded the cell theory with Theodor Schwann - Defined the cell as the basic unit of plant structure and animal structure
https://www.britannica.com/biography/Matthias-Jakob-Schleide

1839 - Theodor Schwann

1839

Cofounded cell theory with Matthias Schleiden in 1838 - Laid the foundation for the cell theory in 1839.

1840 - Albrecht Von Roelliker

1840

Discovered that sperm and eggs are also cells
https://www.softschools.com/timelines/cell_theory_timeline/96/#:~:text=Albrecht%20von%20Roelliker%20discoveres%20that%20sperm%20and%20eggs%20are%20also%20cells.&text=Carl%20Heinrich%20Braun%20reworks%20the,the%20basic%20unit%20of%20life.&text=Rudolf%20Virchow%2C%20a%20German%20physiologist,part%20to%20the%20cell%20theory.&text=This%20translates%20as%20all%20cells%20develop%20only%20from%20existing%20cells.

1855 - Rudolf Virchow

1855

Published a statement based on his observations ¨Omnis Cellula e cellula¨ which means that all cells arise from pre - existing cells - laid the ground work for cellular pathology
https://study.com/academy/lesson/rudolf-virchow-discovery-cell-theory-contributions.html#:~:text=In%201855%20Virchow%20published%20a,arise%20from%20pre%2Dexisting%20cells.&text=Virchow%20used%20the%20theory%20that,disease%20at%20the%20cellular%20level.

1859 - Louis Pasteur

1859

Disproved spontaneous generation - first to prove cells can only form pre - existing cells
https://www.preceden.com/timelines/183224-the-cell-theory#:~:text=Louis%20Pasteur%20contributed%20to%20the,broth%20if%20air%20was%20exposed.