The Test. Tests for Epstein-Barr virus (EBV) antibodies are used to help diagnose infectious mononucleosis (mono) if a person is symptomatic but has a negative mono test.he Test. Tests for Epstein-Barr virus (EBV) antibodies are used to help diagnose infectious mononucleosis (mono) if a person is symptomatic but has a negative mono test.
leaf scar. (botany). A mark on a stem, formed by secretion of suberin and a gumlike substance, showing where a leaf has abscised. 1  Facebook. 2  Twitter.
On well developed branches of Fraxinus americana the leaf scars are often concave along the upper edge and the buds originate well within the curved portion of the leaf scar. The leaf scars of Green and Black ash are not concave along the upper edge or only slightly so.