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.
A normal or desirable cholesterol level is defined as less than 200 mg of cholesterol per deciliter of blood (mg/dL). Blood cholesterol is considered to be borderline when it is in the range of 200 to 239 mg/dL. Elevated cholesterol level is 240 mg/dL or above.