Jan Purkyně

Jan Evangelista Purkyně also written Johannes Evangelist Purkinje (17 December 1787 – 28 July 1869) was a Czech anatomist and physiologist. He was one of the best known scientists of his time. In 1839, he coined the term 'protoplasm' for the fluid substance of a cell.

 Biography 
Purkyně was born in Bohemia, which was then in the Austro-Hungarian Empire, now it is in the Czech Republic. In 1818, he graduated with a degree in medicine, and was appointed  Professor of Physiology. He published two volumes Observations and Experiments Investigating the Physiology of Senses and New Subjective Reports about Vision which contributed to experimental psychology. He created the world's first Department of Physiology at the University of Breslau in Prussia (now Wrocław, Poland), and the world's first official physiology laboratory.

 Discoveries 
He is best known for his discoveries of Purkinje cells and Purkinje fibres. Purkinje cells are large neurons with many branching dendrites found in the cerebellum. Purkinje fibres conduct electrical impulses to all parts of the ventricle of the heart. Other discoveries include Purkinje images, reflections of objects from structures of the eye, and the Purkinje shift, the change in the brightness of red and blue colours as light intensity decreases gradually at dusk. Purkyně also introduced the scientific terms plasma (for the component of blood left when the suspended cells have been removed) and protoplasm (the substance found inside cells.)

Purkyně was the first to use a microtome to make wafer thin slices of tissue for microscopic examination and was among the first to use an improved version of the compound microscope. He described the effects of camphor, opium, belladonna and turpentine on humans in 1829. He also experimented with nutmeg that same year, when he "washed down three ground nutmegs with a glass of wine and experienced headaches, nausea, euphoria, and hallucinations that lasted several days", which remain a good description of today's average nutmeg binge.Shafer, Jack 2010. Stupid drug story of the week: The nutmeg scare, Slate.com Purkyně discovered sweat glands in 1833 and published a thesis that recognised nine principal configuration groups of fingerprints in 1823.Purkyně, Jan Evangelista  1823. Commentatio de examine physiologico organi visus et systematis cutanei. Breslau, Prussia:  University of Breslau Press.

 Cell theory 
Purkyně was, in the opinion of Henry Harris, the true father of the cell theory. The work of Purkyně and his student and collaborator Gabriel Valentin (1810–1883) was "unjustly denigrated by the nationalistic Germans. They have a claim to some priority in the cell theory".Harris H. 1999. The birth of the cell. Yale University Press, New Haven.Chapter 9 

Johannes Müller (1801–1858) also made great contributions. However, it was Theodor Schwann and Matthias Schleiden (1804–1881) who got the credit for the cell theory, despite the fact that some of their observations were not correct, and their credits to previous workers were "a travesty".p97

 References 

Category:1787 births
Category:1869 deaths
Category:Czech scientists
Category:Physiologists
Category:Academics of the University of Wrocław