Cell Theory

Experimentation and animal classification

300

Aristotle was known for his experimentaions and formed some animal classifications that we still use today.

Tree plant experiment

Nov 9, 1500

Jan Baptist von Helmont did an experiment in which he shows that the substance of a plant derives from water and air, the first description of photosynthesis.

Microscope

Nov 7, 1595

Zacharias Jansen invented the first compound microscope.

Cork cells

Nov 7, 1665

Robert Hooke observed cork cells and inspired Leeuwenhoek.

"little animals"

Nov 7, 1674

Antoni van Leeuwenhoek reported that he had observed "little animals."

Die Zeugung (The Conviction)

Nov 11, 1805

Oken proposes that “all organic beings originate from and consist of vesicles or cells.

Brownian motion

Nov 9, 1828

Robert Brown established that tiny particles of inorganic materials such as carbon and metals display Brownian motion.

Plant cells

Nov 7, 1836

Matthias Schleiden recognizes that all parts of plants are composed of cells.

First cell theory statement

Nov 7, 1839

Theodor Schwann published "Microscopic Investigation on the Accordance in the Structure and Growth of Plants and Animals," which included the first cell theory statement: All living things are made up of cells.

Sperm and egg cells

Nov 9, 1840

Albrecht von Roelliker realized that sperm cells and egg cells are also cells.

Pre-existing

Nov 7, 1858

Rudolf Virchow extended their work by proposing that all living cells came from pre-existing cells.

Death of Spontaneous Generation

Dec 1, 1862

Louis Pasteur proved that flasks of broth and water did not spoil when organisms were prevented from entering them.