Cholesterol functions to immobilise the outer surface of the membrane, reducing fluidity. It makes the membrane less permeable to very small water-soluble molecules that would otherwise freely cross. It functions to separate phospholipid tails and so prevent crystallisation of the membrane.

What is cholesterol molecule?

cholesterol, a waxy substance that is present in blood plasma and in all animal tissues. Chemically, cholesterol is an organic compound belonging to the steroid family; its molecular formula is C27H46O. In its pure state it is a white, crystalline substance that is odourless and tasteless.

What is total cholesterol?

Total cholesterol is the total amount of cholesterol in your blood. Your total cholesterol includes low-density lipoprotein (LDL, or “bad”) cholesterol and high-density lipoprotein (HDL, or “good”) cholesterol. Cholesterol is a waxy, fat-like substance found in every cell in your body.

How many cholesterol molecules are there?

LDL particles are the major blood cholesterol carriers. Each one contains approximately 1,500 molecules of cholesterol ester. LDL molecule shells contain just one molecule of apolipoprotein B100, recognized by LDL receptors in peripheral tissues.

How does cholesterol maintain fluidity?

Cholesterol acts as a bidirectional regulator of membrane fluidity because at high temperatures, it stabilizes the membrane and raises its melting point, whereas at low temperatures it intercalates between the phospholipids and prevents them from clustering together and stiffening.

Why is cholesterol nonpolar?

Most of the cholesterol molecule in non-polar and therefore associations with the non-polar fatty acid tails of the phospholipids. However, the hydroxyl group (-OH) on cholesterol carries a negative charge and therefore associates with the polar environment of water either inside the cell or outside.

Where are cholesterol molecules found?

Cholesterol is an animal sterol found in the body tissues (and blood plasma) of vertebrates. It can be found in large concentrations within the liver, spinal cord, and brain. Cholesterol is an important component of the membranes of cells, providing stability.

What is the normal total cholesterol?

Cholesterol levels for adults Total cholesterol levels less than 200 milligrams per deciliter (mg/dL) are considered desirable for adults. A reading between 200 and 239 mg/dL is considered borderline high and a reading of 240 mg/dL and above is considered high. LDL cholesterol levels should be less than 100 mg/dL.

What is the molecular formula of cholesterol?

C27H46OCholesterol / Formula