Question

Why is blood plasma pale yellow in color?

Answer 1

Hint: Blood plasma is a component of blood responsible for holding the whole blood in suspension. It is the liquid part of the blood carrying cells and proteins throughout the body thus making up 55% of the body's total blood volume.

Complete answer:
Blood plasma is the intravascular fluid part of extracellular fluid. It contains dissolved proteins (e.g., serum albumins, globulins, and fibrinogen), glucose, clotting factors, electrolytes, hormones, carbon dioxide, and oxygen. It helps in intravascular osmotic effect thus keeping a balance of electrolyte concentration and protecting the body from infections.
Plasma proteins: Albumins are the most common plasma proteins responsible for maintaining the osmotic pressure of blood. The increased viscosity of blood prevents fluid from entering the bloodstream from outside the capillaries.
Globulins are the second most common type of protein in the blood plasma. Important globulins include immunoglobulins that are important for the immune system and transport hormones around the body.
Color: Plasma is yellow colored due to bilirubin, carotenoids, hemoglobin, and transferrin. In some cases, plasma has varying shades of orange, green, or brown. Green color can be due to ceruloplasmin or sulfhemoglobin. This may be due to medicines that can form sulfonamides once ingested. Dark brown/reddish color appears due to hemolysis. It is transparent, but sometimes opaque also due to the elevated content of lipids.

Note: Plasma donation: Plasma as a blood product prepared from blood donations is used in blood transfusions, like fresh frozen plasma or Plasma Frozen within 24 hours after phlebotomy. When donating whole blood, O- is the most desirable and is a universal donor, since it has neither A nor B antigens and can be safely transfused to most recipients. Type AB+ is a universal recipient type. Plasma blood donation centers collect plasma from AB donors only, since they lack antibodies that may cross-react with recipient antigens. Also, AB is considered a universal donor for plasma.