‘All living things are composed of cells and cell products.’ Known as ‘cell theory’, German physiologist, Theodor Schwann, was the co-originator of this term in 1836. Schwann, born on this day in 1810, was an expert in microscopy and examined animal tissue while working on the development of tadpoles. He was the first to establish the basic principle of embryology as he noticed that the ovum [female egg] is a single cell that, after fertilisation, divides and becomes a complete organism. Among many other things, he discovered the digestive enzyme pepsin, realised the organic nature of yeast and coined the term ‘metabolism’. Never shying away from controversy, Schwann challenged the popular theories of the day and continued in his cellular studies until he died. Schwann’s ‘cell theory’ is still at the core of basic biology today and is the one of the first things taught in school science classes.
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.