Macrocytosis - Pathophysiology. 1  The most common cause of macrocytic anemia is megaloblastic anemia, which is the result of impaired DNA synthesis. 2  Vitamin B-12 and folate coenzymes are required for thymidylate and purine synthesis; thus, their deficiency results in retarded DNA synthesis.
(You may want to read the articles about Scales, the Major Scale, or Key Signatures first.) There are 12 different Major Scales: One with no sharps or flats, 4 with sharps, 4 with flats, and 3 with either sharps or flats depending upon enharmonic spelling. Major Scales with no sharps or flats: C Major. Major Scales with sharps: D, E, G, A. Major Scales with flats: E-flat, F, A-flat, B-flat.
The minor scale can be described in two different ways. One way is to consider it as the sixth mode of a major scale, while the other is to call it a variation of the major scale, with the third scale degrees always lowered (or altered) and the sixth and seventh degrees often lowered.