Blood And Major Systems Of The Body - part 1

The hemopoietic system

The tissues involved in the process of forming red blood cells along with the bone marrow, lymph nodes (tiny organs of the immune system in the shape of beans) and the spleen are all connected to one another by means of diminutive vessels called lymphatic ducts.

Lymph node system: As mentioned above, the lymph nodes are very small organs of the immune system resembling beans wherein blood cells of the white lymphocyte replicate and multiply. The lymph nodes perform the crucial task of combating contagions. The volume of the lymph nodes augments in conditions, such as cancers, inflammatory ailments and infections and this aptitude of the lymph nodes is known as lymphadenopathy. Unfortunately, while the lymph nodes fight cancer, at times, they may even be ideal locations for cancerous growths and this is often seen in the instance called lymphoma. In fact, the lymph nodes are present in almost all parts of the body and they are present in a particular area of the body depending on the anatomical region wherein they are found. Few of the major varieties of lymph nodes include abdominal, cervical, thoracic and inguinal.
Lymphatic ducts: The tiny vessels that connect the lymphatic nodes with one another are called lymphatic ducts. In the instance of the body being infected by any microbe, the white blood cells pass through the lymphatic ducts to arrive at the lymph nodes. The white blood cells or leukocytes replicate and multiply in numbers inside the lymph nodes with a view to combat the contagion in a better manner. In the instance of any cancerous growth inside the body, this route often provides a means that enables the cancer to spread. What is worse is the fact that the cancerous cells are able to disengage from a tumor and utilize the lymphatic ducts to assail the local nodes, thereby molding the spread of cancer at the nodes (node metastases).
Spleen: The spleen is a purplish-red organ that is like an oval-shaped petite bag filled with blood and is located in the upper-left part of the abdominal cavity. The size of this organ found in vertebrates is similar to that of a tomato and, like the vegetable, it is also very delicate. The major function of the spleen is to get rid of the 'old' or 'mature' red blood cells that have been engaged in transporting oxygen to the different parts of the body for more than 120 days and are in the initial process of 'aging'. The spleen is able to identify such cells and collects them from the bloodstream with the purpose of eliminating them from the body.
In addition, the spleen also performs a vital role in combating contagions by getting rid of bacteria as well as specific antigens from the blood supply system. On many instances, the size of the spleen enlarges, a disorder known as splenomegaly, and a number of ailments are responsible for this condition. Diseases that are frequently associated with splenomegaly include liver ailments, viral contagions, malignant maladies like leukemia and lymphoma as well as inflammatory conditions. Although it may seem to be incredible, in such cases there are possibilities of the size of the spleen swelling to the dimension of a football! When such conditions do occur, the spleen becomes highly susceptible to minimum strain.

The cardio-respiratory system

When we talk about the cardio-respiratory system, many people think that the term only implies to the heart and the breathing process. However, this is not true. In fact, the cardio-respiratory structure or system basically comprises the heart, the lungs as well as the major blood vessels. The main functioning of the heart is to pump blood and make sure that blood containing oxygen reaches all the organs of the body. In fact, the heart can be divided into two segments - the right portion of the heart and the left portion of the heart.

The right section of the heart obtains blood bereft of oxygen from the different organs, including the muscles. This blood, containing carbon dioxide, passes through the veins and enters the superior and inferior vena cava. Subsequently, the right segment of the heart pumps this blood to the lungs, where the carbon dioxide is exchanged for oxygen inhaled by the organ. In the process, the bluish blood from the right heart is changed to vividly red hued blood in the lungs. From the lungs, blood passes on to the left segment of the heart that pumps the oxygen-rich blood to the different parts of the body.

Under normal circumstances, the heart beats or pumps blood over a 100,000 times every day. Every moment, the heart regulates its beat and the vigor of its tightening that denotes the change in the requirement of oxygenated blood by the different parts of the body. Nevertheless, a number of hematological situations are likely to boost the heart beat, for instance, in patients enduring anemia or any contagion.

The central nervous system (CNS)

CNS or the central nervous system comprises a chain of organs that make up the nervous tissues and all these tissues are intimately connected to one another. The central nervous system incorporates the brain, the brain stem, the cerebellum as well as the spinal cord. Together, the cerebellum, the brain and the brain stem constitute several million cells known as neurons. It is important to note that neurons are unable to proliferate. They correspond with each other by means of an arrangement including diverging components, the entire length of which may be more than one meter.

In fact, the spinal cord is composed of such arrangement of split elements that pass through the middle of the vertebra in a channel called the vertebral canal. In fact, the spinal cord is segregated into many sub-divisions that are called nerves. It may be noted here that any fracture in or smashing up of the spinal cord causes permanent paralysis. As the central nervous system is one of the most vital parts of the body, it is surrounded by cerebrospinal fluid that flows continuously to protect as well as nurture this. Before any physician takes embarks on a puncture of the lumbar, he or she normally eliminates quite a few milliliters of the cerebrospinal fluid.

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