This suggests that people are born with a dislike of heights. However, most children and adults are a bit nervous around heights, but they don't have a phobia. Many scientists think that a phobia is a learned response to either a parent's fear of heights or a traumatic experience in childhood, like a fall. Show the video to your parents and friends.
Causes Of Melena. Black stool or melena causes include: 1  Peptic ulcer that includes stomach ulcer, duodenal ulcer. 2  Stomach cancer. 3  Patient on anti-coagulant drugs such as Warfarin may cause melena. 4  Gastritis (inflammation of stomach) and esophageal varices.5  Hemorrhagic blood disease such as purpura.ymptoms of melena or blood in stool are: 1  Patient complains change of stool color to his medical attendant; it is dark black like coal tar. 2  Anemia is most important sign noted in patients with melena.
The term melena is used to describe a black, tarry appearing feces, which occurs due to the presence of digested blood in the intestines, or to internal bleeding that has passed into the intestine. Melena is typically seen due to bleeding in the upper portion of the gastrointestinal tract. It has also been seen in dogs after they have ingested a sufficient amount of blood from the oral cavity or respiratory tract. It is not a disease in itself but a symptom of some other underlying disease.