(Redirected from Blood plasma)
The fluid portion of the blood, mainly composed of water (90%) but also contains a range of proteins (6.5-8%) and low molecular weight substances (2%). When the blood is separated using centrifugation plasma is viewed as a pale yellow liquid and forms 55% of the total volume of the blood. Plasma holds a key role in the maintaining of osmotic pressure and acts as a transport medium for a range of molecules. Serum is plasma after the removal of clotting factors II, V, VIII and fibrinogen.
Plasma Proteins[edit | edit source]
Over 100 different types of plasma protein exist but they can be grouped into 3 fractions; Plasma Albumin, Plasma Globulin and Fibrinogen.
|Protein||Function||Site of synthesis|
||α and β in liver
Ύ by lymphocytes
|Fibrinogen||Buffering and hemostatic role||Liver|
Alternatively it is possible to group plasma proteins according to their function;
|Functional Catergory||Proteins Included||Role|
|Proteins of the Acute Phase||
|Plasma Proteolytic Enzymes||
|Plasma Protease Inhibitors||Antithrombin III||Anticoagulation|
||Transport of specifc molecules|
Low Molecular Weight substances[edit | edit source]
These substances include K+, Na+, Ca2+, HCO3- , glucose and urea. These molecules and ions all produce osmotic pressure, also in the case of HCO3- forms the principle buffering system of the blood. The combined effect of these molecules results in plasma having an osmolarity of 280-290 mOsm/L . This osmolarity is equal to that of 0.9 % saline solution hence its use to hydrate patients intravenously.
Links[edit | edit source]
Related Articles[edit | edit source]
Changes in Serum Protein Levels
Bibliography[edit | edit source]
POKORNÝ, Prof. MUDr. Jaroslav. Principles of Homeostasis, Blood, Plasma [lecture for subject Principles of Homeostasis, Blood, Plasma, specialization Physiology, Medicine Charles University]. Prague. 25.10.2013.
MESCHER, Antony. Junqueira's Basic Hitsology. 12th edition. 2010. ISBN 9780071271905.
BARRETT, Kim – BOITANO, Scott – BARMAN, Susan, et al. Gangon's : Review of Medical Physiology. 23rd edition. 2010. ISBN 9780071270663.