Hans Christian Gram was the man who found a difference in the structure and biochemical function of samples while treating a smear of bacteria with a crystal violet stain, followed by an iodine solution and organic solvent.
Hans Christian Gram was a Denish bacteriologist noted for his development of the Gram Stain during the 19th to 20th century. He was born in Copenhagen on September 13, 1853. He discovered a staining technique, which is used to identify and classify different types of bacteria. His technique is still used today after even he died long ago.
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This picture shows the work of Hans Christian Gram