During the VLDL to LDL transition, an apolipoprotein buried just below the surface of the VLDL called ApoB-100, becomes exposed. ApoB-100 identifies the lipoprotein as an LDL particle to other cells. Cells which require cholesterol recognize ApoB-100 and capture the LDL, so that the cholesterol it contains can be brought into the cell. Each LDL particle expresses exactly one ApoB-100 molecule, so measurement of Apo-B100 levels serves as a much more accurate indicator of LDL number than LDL-C (LDL cholesterol) level.