Rotation is the act of raising the nose of an aircraft (by pulling back slightly on the control yoke or stick) during the take-off roll, so that it leaves the runway. Rotation allows for a precise, positive departure from the runway.
Crenation is the loss of water from an animal cell due to osmosis. Lysis is the rupture of the cell wall due to too much water moving into an animal cell due to osmosis. Both â¦crenation and lysis have drastic effects on the animal cell.
Causes [edit]. The most common cause of melena is peptic ulcer disease. Any other cause of bleeding from the upper gastrointestinal tract, or even the ascending colon, can also cause melena.Melena may also be a sign of drug overdose if a patient is taking anticoagulants, such as warfarin.owever,the most prominent and helpful sign in these cases of malignant tumors is haematemesis. It may also accompany hemorrhagic blood diseases (e.g. purpura & hemophilia). Other medical causes of melena include bleeding ulcers, gastritis, esophageal varices, Meckel's diverticulum and Mallory-Weiss syndrome.