2. Once you recognize that this is a single replacement problem, determine whether the non-bonded element is a cation or anion. Then determine which element it will replace. Remember cations can only replace cations and anions can only replace anions.
If you haven't eaten for several hours and your blood sugar level drops, another hormone from your pancreas called glucagon signals your liver to break down the stored glycogen and release glucose back into your bloodstream.
Quick Answer. Diseases that cause low white blood cell counts include aplastic anemia, human immunodeficiency virus, leukemia and lupus, according to Mayo Clinic. Other causes include rheumatoid arthritis, Crohn's disease and infections such as tuberculosis, reports MedlinePlus.