Editing Lipoprotein (section)

===Plasma lipoprotein particles {{anchor|Plasma lipoproteins particles}}===
{{More citations needed|date=October 2021}}
Because fats are insoluble in water, they cannot be transported on their own in extracellular water, including blood plasma. Instead, they are surrounded by a hydrophilic external shell that functions as a transport vehicle. The role of lipoprotein particles is to transport fat molecules, such as [[triglyceride]]s, phospholipids, and cholesterol within the extracellular water of the body to all the cells and tissues of the body. The proteins included in the external shell of these particles, called apolipoproteins, are synthesized and secreted into the extracellular water by both the [[small intestine]] and [[liver]] cells. The external shell also contains phospholipids and cholesterol.

All [[cell (biology)|cells]] use and rely on fats and cholesterol as building blocks to create the multiple [[cell membrane|membranes]] that cells use both to control internal water content and internal water-soluble elements and to organize their internal structure and protein enzymatic systems. The outer shell of lipoprotein particles have the hydrophilic groups of phospholipids, cholesterol, and apolipoproteins directed outward. Such characteristics make them soluble in the salt-water-based blood pool. [[Triglyceride]]s and [[cholesteryl esters]] are carried internally, shielded from the water by the outer shell. The kind of apolipoproteins contained in the outer shell determines the functional identity of the lipoprotein particles. The interaction of these apolipoproteins with enzymes in the blood, with each other, or with specific proteins on the surfaces of cells, determines whether triglycerides and cholesterol will be added to or removed from the lipoprotein transport particles.

'''Characterization in human plasma'''<ref>{{Cite book|title=Biochemistry|last=Satyanarayana|first=U.|date=2002|publisher=Books and Allied|isbn=8187134801|edition=2nd|location=Kolkata, India|oclc=71209231}}</ref>
{| class="wikitable"
|+
|
!Chylomicrons
!VLDL
!LDL
!HDL
|-
|[[Serum protein electrophoresis|Electrophoretic mobility]]
|Origin
|Pre-Beta
|Beta
|Alpha
|-
|[[Density]]
|less than 0.96
|0.96-1.006
|1.006-1.063
|1.063-1.21
|-
|[[Diameter]] (nm)
|100-1000
|30-90
|20-25
|10-20
|-
|Apolipoproteins
|B<sub>48</sub>, Al, All
|B<sub>100</sub> CI, CII
|B<sub>100</sub>
|AI, AII, CI
|-
|'''Composition'''<br>(% of total content)
|
|
|
|
|-
| · Protein
|2
|10
|20
|40
|-
| · Lipid
|98
|90
|80
|60
|-
|'''Lipid component'''<br>(% of total lipid content)
|
|
|
|
|-
| · Triglycerides
|88
|55
|12
|12
|-
| · Cholesteryl esters
|4
|24
|59
|40
|-
| · Phospholipids
|8
|20
|28
|47
|-
| · Free fatty acids
| -
|1
|1
|1
|}