Cholesterol is a biomolecule used in the cellular membrane of the cell. It provides structure for the cell, and it prevents certain fluids and substances from entering the cell. Cholesterol is synthesized by the liver, but it's also available in the diet.
Significance
Cholesterol plays a significant role in the structure of the outer membrane of the cell. It is also a building block for hormones like androgens and estrogen.
Structure
The ring structures in cholesterol are the carbon skeleton that makes cholesterol insoluble. Cholesterol contains three rings: two six-carbon rings and one five-carbon ring.
Types
The main two types of cholesterols are high-density lipoprotein, or HDL, and low-density lipoprotein, or LDL. The other two types of cholesterol less commonly known are very-low-density lipoproteins, or VLDL, and chylomicrons.
Synthesis
Cholesterol is synthesized in the liver. However, cholesterol is also obtained in the diet. Cholesterol is found in animal products like red meat and eggs and some vegetables.
Warning
Too much cholesterol is associated with heart disease. People are encouraged to avoid fatty foods, especially saturated fats. Cholesterol can lead to atherosclerosis, high blood pressure and a heart attack.
