Blood Composition and Function – Red Blood Cells and White Blood Cell

We all know how important blood is and the serious dangers associated to blood loss. Yet, few of us have clear understanding about the function of blood.

Blood is a special type of tissue that is formed of cells and liquid plasma. It circulates through the blood vessels that are part of the human circulatory system. The different types of cells that pass through these vessels include red blood cells (erythrocytes), white blood cells (leukocytes) and thrombocytes (important for blood clotting).

The cells form approximately 45 percent of blood’s composition.

Since it passes through the entire body, blood has one important function – providing different types of substances to other tissues.

Apart from carrying oxygen to organs in the body, blood is responsible for the disposal of waste products like carbon dioxide.

Further, each type of blood cells has its specific function. White blood cells are important components of the human immune system. Their main aim is to protect the organism against pathogens.

Plasma is the liquid that surrounds the blood cells. It provides the environment that the blood cells need in order to perform their tasks.

Said in simple words, blood and the circulatory system ensure the survival of the human organism. Blood provides each single cell with the nutrients and the substances that it needs in order to function properly.

On the other hand, the circulatory system is also responsible for ‘cleaning’ the organism from the waste that forms as part of various vital processes. When it brings oxygen to organs, blood takes away carbon dioxide. The disposal process ends with every exhalation, when the carbon dioxide brought by red blood cells to the respiratory system leaves the body.

Blood carries nutrients apart from oxygen. Once the digestive system has finished the process of digesting food, blood distributes lipids, carbohydrates and proteins to all parts of the body. Some of these nutrients are directly used while others are stored.

Blood has yet another very important transport function. Apart from oxygen, nutrients and waste, it carries hormones throughout the body. It also carries immune system cells and other bodily substances. Blood ‘coordinates’ the transportation and delivery of all important signals that keep the body healthy and functioning.

If all these seem insufficient, you can consider the several additional functions that blood is responsible for. It regulates the temperature of the body and removes excess heat from active tissue. Blood also regulates the Ph level of the body.

The final protective function is related to wounds. Whenever a breakage of blood vessels occurs, blood is able to clot in order to prevent the loss of bodily fluids.

Sources of information:
University of California, San Francisco, Medical Center