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Blood plays a vital role in the human body for survival and therefore is regarded as one of the most important components of life. Almost any animal that possesses a cardiovascular system has blood. From an evolutionary perspective, blood was blamed to have risen from a kind of cell that was liable for phagocytosis and nutrition. Billions of years later, blood and therefore the cardiovascular system have drastically helped the evolution of more complex lifeforms.

What is Plasma?

Plasma is a liquid portion of blood which contains extra cells and therefore is also known as being extracellular in nature. It is transparent and pale yellow or straw-colored. It is mainly composed of clotting factors and other protein molecules. Overall 50 to 55 percent of total blood volume is plasma. 

Plasma in blood mainly comprises 80 to 90 percent of water and therefore the other 10 percent consists of salts, lipids, nutrients, enzymes and hormones.

Proteins, immunoglobulin, clotting factors and fibrinogen are the contents of plasma in blood cells. This protein helps in coagulation factors and also maintains serum pressure. 

Features of Blood Plasma

Compared to other blood cells, plasma is relatively transparent and other blood cells are freely suspended within the plasma. Other special features of blood plasma are:

  1. It contains fibrinogen, immunoglobulin, electrolytes and proteins.

  2. Plasma is the medium of the blood, which consists of differing types of blood cells. 

  3. Approximately 1025 kg/m3, or 1.025 g/ml counts as the density of the blood plasma. 

  4. Plasma is the medium of the blood, in which different types of blood cells exist.

  5. Blood plasma can be preserved for more than a year and can be used too as it has a long shelf life. 

Functions of Blood Plasma

Plasma springs from the liquid portion of the blood, and is routinely utilized in blood type test experiments for determining the patient’s blood type .

Other important functions of blood plasma are:

Along with other nutrients, plasma also contains important proteins and other essential components necessary for overall health. Patients with conditions like liver failures and other life-threatening injuries are treated with Blood plasma transfusions.

Plasma is fluid particles of the blood, which contains the clotting agent fibrinogen, and functions by preventing the excessive flow of blood during injury.

Blood plasma also contains proteins, which help within the transportation of glucose and other nutrients to different parts of the body.

Plasma in blood plays a vital role in the regulation of body temperature and also is responsible for controlling blood pressure and therefore is referred to as the matrix of blood. It consists of clotting factors, proteins compounds and serum. It consists of 92 percent water with proteins, salts, lipids and glucose. Plasma is the main medium for body waste transportation.

Other than the blood coagulation, this fluid matrix also functions by circulating both red blood cells and white blood cells, hormones, blood platelets and other digested food particles.

As mentioned above, plasma also functions as the main carrier for the transportation of excretory products by carrying away waste materials from the cells to the excretory organs where it is flushed out of the body.

Functions of Blood

Blood is responsible for the following body functions:

Fluid Connective Tissue

Blood is a fluid connective tissue composed of 55% plasma and 45% formed elements including WBCs, RBCs, and platelets. Since these living cells are suspended in plasma, blood is understood as a fluid animal tissue and not just fluid.

Provides Oxygen to the Cells

Blood acts as a transporter of blood to other cells of the body as it absorbs oxygen from the lungs and transports it to different cells of the body. The waste carbon dioxide moves from the blood to the lungs and exhales.

Transports Hormone and Nutrients

The digested nutrients like glucose, vitamins, minerals, and proteins are absorbed into the blood through the capillaries within the villi lining the tiny intestine.

Along with the blood, the hormones that are secreted by the endocrine glands are also transported by the blood to different organs and tissues of the body. 


Blood helps to take care of the interior blood heat by absorbing or releasing heat.

Blood Clotting at Site of Injury

The platelets help within the clotting of blood at the location of injury. Platelets along side the fibrin form clot at the wound site

Transport of Waste to the Kidney and Liver

Blood enters the kidney where it's filtered to get rid of nitrogenous waste out of the plasma . The toxins from the blood also are removed by the liver.

Protection of Body Against Pathogens

The White Blood Cells fight against infections. They multiply rapidly during the infections.

FAQ (Frequently Asked Questions)

1. Why the Color of Blood Red?

Ans - Blood contains haemoglobin, which contains heme (iron). It is responsible for giving blood a characteristic red appearance.

2. Name the Major Functions of Blood.

Ans - The basic functions of blood are - 

  • Helps in homeostasis

  • Provides oxygen to the cells

  • Transports hormone and nutrients

  • Helps to in the clotting process.