One of the characteristic features of a living cell is that it controls the exchange of electrically charged ions across the cell membrane and therefore the electrical potential of its interior relative to the exterior. This Scholarpedia page is a basic introduction into the mechanisms underlying this process.
Here are the ranges for total cholesterol in adults: 1  Normal: Less than 200 mg/dL. 2  Borderline high: 200 to 239 mg/dL. 3  High: At or above 240 mg/dL.
High cholesterol usually refers to a person's low-density lipoprotein, or LDL, numbers because this is a risk factor for atherosclerosis. According to the Mayo Clinic, ideal LDL cholesterol numbers are below 129 milligrams per deciliter, whereas anything above 160 milligrams per deciliter is considered high.