AP BIOLOGY

Detailed explanation-1: -Robert Remak (26 July 1815 – 29 August 1865) was a Jewish Polish-German embryologist, physiologist, and neurologist, born in Posen, Prussia, who discovered that the origin of cells was by the division of pre-existing cells.

Detailed explanation-2: -He demonstrated the existence of the medullary nerve sheath and its production in the process of structured cell division. Remak also was the first to demonstrate that the cerebral cortex consists of six layers and to assert that there are three germ layers in the early embryo and not four.

Detailed explanation-3: -The third part, which asserts that cells come from preexisting cells that have multiplied, was described by Rudolf Virchow in 1858, when he stated omnis cellula e cellula (all cells come from cells).

Detailed explanation-4: -(a) Rudolf Virchow (1821–1902) popularized the cell theory in an 1855 essay entitled “Cellular Pathology.” (b) The idea that all cells originate from other cells was first published in 1852 by his contemporary and former colleague Robert Remak (1815–1865).

Detailed explanation-5: -Rudolf Virchow confirms that all cells must come from pre-existing cells. (There is some evidence that this idea was stolen from Polish scientist Robert Remak.) These events gave way to the modern cell theory, which states: All living things are composed of one or more cells.