Confidence votes 11. According to Wikipedia, the width of the Atlantic Ocean at its narrowest point is 2,848 kilometers (1,770 mi) between Brazil and Sierra Leone.
What causes PNH? It is not fully understood why people develop PNH. Inside the bone marrow, blood cells are made by stem cells (the seed cells of the marrow). PNH occurs due to a change (or mutation) in a gene in one of the stem cells in the bone marrow. This mutation happens in a gene called PIG-A and the cells made by this stem cell lack certain proteins on their surface making them âweakerâ than normal blood cells.
Hypochromia is characterized by an increase in central pallor. It is said to be present when greater than 1/2 of the cell diameter has central pallor. Hypochromia is caused by a deficiency in the production of hemoglobin, which is usually the result of iron deficiency caused by chronic hemorrhage. Poikilocytes are frequent in iron-lack anemia and are thought to result from oxidation of the erythrocyte membrane resulting in fragmentation.