Melanotic refers to MELANIN not MELENA #medicine #doctor #humor #doctorsofinstagram #medreels #melanin GASTROINTESTINAL HEMORRHAGE (2): Melena. Melena, the passage of black, tarry stools, usually implies blood loss greater than 500 ml originating anywhere between the oropharynx and the right hemicolon. Melena occurs most often, Melanin Definition, Types & Function Lesson Study.com The Quantity of Blood Required to Produce a Tarry Stool. How much? Melena, characterized by black tarry stools, can occur with as little as 50 cc of blood in the stomach. How Melanocyte differentiation and mechanosensation are differentially modulated by distinct extracellular matrix proteins EMBO Reports Springer Nature Link