Triacylglycerols, cholesterol and phospholipids are associatively insoluble in aqueous solution. Thus, they are transported around the body in the blood as parts of lipoproteins.  These circular micelle-like particles having of a hydrophobic core of triacylglycerols and cholesterol esters surrounded by an amphipathic coat of protein, cholesterol and phospholipid. The protein elements of lipoproteins are called as apolipoproteins (or apoproteins).  At least 10 variant apoproteins are found in the variant human lipoproteins. Their purpose are to help solubilize the hydrophobic lipids and to act as cellular targeting signals. Lipoproteins are classify into five collections on the basis of their physical and functional properties are verified in the table:

-  Chylomicrons are the main and least dense lipoproteins. They transport dietary (exogenous) cholesterol and triacylglycerols   from the intestines to other tissues in the body.

-  Very low density lipoproteins (VLDLs), intermediate density lipoproteins (IDLs) and low density lipoproteins (LDLs) are a group of connected lipoproteins that transport internally produced (endogenous) triacylglycerols and cholesterol from the liver to the tissues.

-  High density lipoproteins (HDLs) transport endogenous cholesterol from the tissues to the liver.