Difference Between Plasma And Serum

Plasma and serum are both present in the blood, but the percentage of plasma is more in contrast to serum. Plasma is a pale-yellow fluid that can be obtained from anticoagulant-containing vials, which prevents the clotting of blood, and after centrifugation, plasma will be obtained. Serum is also yellow in color and is obtained after centrifugation of clotted blood. The percentage of plasma in blood is 55%. Both serum and plasma are used for diagnostic purposes.

Difference Between Plasma and Serum

Now that quantities we know the basics of plasma and serum, let us look at the key differences between them. 

Plasma	Serum
It is the fluid part of the blood with clotting properties.	It is the fluid part of the blood without any clotting properties.
It is present in larger quantities in the blood.	Comparatively, it is not present in such large quantities in the blood.
It is obtained by direct centrifugation.	It requires clotting before centrifugation.
The preparation of plasma is quick since it is not coagulated.	The preparation of serum is not that quick.
It requires addition of anticoagulants while its preparation, which might give incorrect results.	The same is not true for serum and it is a better liquid for testing.
Plasma necessarily requires the use of anticoagulants for separation.	The serum does not require the use of anticoagulants for separation.
It is a medium where cells are suspended and not dissolved.	Serum simply contains proteins, electrolytes, hormones, antibodies and antigens.
Plasma samples may also form clots that will lead to errors.	Such difficulties are not faced with a serum sample.
It is mainly important for blood clotting.	It is mainly important for antibodies.
It has 95% water.	It has 90% water.
It can be stored in frozen form for even a year.	It can be stored at a maximum of 6 degrees for a few days.
Its density is 1025 kg/m3	Its density is 1.025g/ml
It is used in case of insufficient blood cells.	It is mostly used in blood tests.

Characteristics of Plasma and Serum

Here are the key characteristics or facts about plasma or blood plasma

Characteristics	Plasma	Serum
Color	Straw color	Clear yellow
Volume	55% of total blood	Less than plasma
Compostion	Lipid, glucose, albumin, globulin	Hormones, Ag and Ab, clotting factors
Gases	CO2	O2
Useful components	metabolites, components to maintain BP	Na, Ca, Mg, Cl
Density	1025 kg/m3	1.0242 g/ml

What is Plasma?

Plasma is the fluid part of blood, present in most of the other constituents of blood. Since this is the liquid part of the blood, a lot of nutrients and proteins are dissolved here, and it also plays a significant role in the process of transportation. 

Functions of Plasma

Here are the main functions of Plasma:

1. Transportation of waste products. 
2. Balancing of electrolyte concentration thus preventing infections and blood disorders. 
3. Clotting of blood in case of wounds. 
4. Balancing pH helps the cells function normally. 
5. Balancing body temperature. 

What is Serum?

The serum is that solute of the blood that works just like plasma except that it does not help in blood clotting. Being fluid, it also contains various proteins along with electrolytes and antibodies dissolved in it. But like Plasma, the serum also does not contain RBCs, WBCs or platelets. 

Functions of Serum

Here are the main functions of Serum:

1. Helps in the detection of the presence of drugs. 
2. Used in immunotherapy, that is, the treatment of a disease whose antibodies are present in the blood serum.  
3. It is also used in protein electrophoresis.  

FAQs about Serum and Plasma

1. What are two Major Differences between Serum and Plasma?

Serum is the liquid left after blood clotting, while plasma is the liquid that remains when an anticoagulant is added to prevent clotting. Plasma, a clear, straw-colored fluid, represents the undiluted extracellular portion of blood.

2. Why Serum is used Instead of Plasma?

Serum, constituting a larger proportion of blood than plasma, is extensively utilized in research due to its efficient removal of unwanted red blood cells, resulting in greater volume per unit of blood.

3. What Color is Plasma?

Blood plasma, the yellow liquid component in which blood cells are suspended, varies in color from barely yellow to dark yellow, occasionally with brown, orange, or green hues.

4. What is the Function of the Serum?

Albumin molecules in the serum bind to substances, facilitating their transport. Human serum aids in the transportation of fatty acids and thyroid hormones, influencing a wide range of cells in the body.

5. What Percentage of Blood is Serum?

Serum, comprising the non-clotting portion of plasma, constitutes about 55% of blood volume, while red blood cells make up 45%, and white blood cells and platelets together account for approximately 1%.