As I start my travel, I move from the right femoral vein and travelled through the arm to the lung. As I reached lungs, I found quite a strange place where the blood grew extremely rich in oxygen and I was just overwhelmed with such a flow of oxygen. The difference between the quantity of oxygen in the blood in the right femoral vein and in the lung was striking.
However, it was quite natural that the blood was rich in oxygen, when I got into the lung because the lung is an essential respiration organ. It is due to the lung humans as well as other species having the similar structure can breathe. Lungs receive oxygen inhaled from the atmosphere and enrich blood that absorbs oxygen and delivers it to other organs of human body, including vitally important ones, such as heart. In fact, oxygen is like a fuel for blood and organs. The lung had a spongy and soft texture. In addition, the lung was honeycombed with epithelium that has a much larger surface area in total than the outer surface area in total of the lung itself. As human breathe, the lungs contracts under the pressure of the diaphragm and the absorption of oxygen occurs. After that oxygen spreads throughout the body through alveoli.
At the same time, the lung provides the body with oxygen, while the oxygen is supplied by blood through blood vessels to all organs of human body. The supply of blood and oxygen is essential for the normal development of all organs and immune system. In fact, the immune system of human body is a vitally important system because it protects human body from infections and bacteria that may affect consistently health of humans and condition of human body. The immune system is crucial for the maintenance of human body because it protects human body from dangerous influences from the outside world. the immune system helps human body to avoid infections, diseases, or other unwanted biological invasion. In this respect, it is important to distinguish specific and non-specific components of the immune system.
The non-specific components of the immune system act either as barriers or as eliminators of many pathogens irrespectively of their antigenic specificity. The non-specific immunity is innate. This is the natural resistance of human body to external influences and humans are born with the non-specific components of the immune system. The non-specific immune components provide the body with resistance to diseases and bacteria through several physical, chemical, and cellular processes (April, 2009). As bacteria or microbes encounter the epithelial layers, physical barriers arise. Physical barriers are presented by the skin and mucous membranes. At the chemical level of the non-specific immune system, bacteria and microbes confront antimicrobial substances produced by non-specific immune components. At this stage, fever and phagocytic activity may begin because of the inflammatory response of the immune system to microbes and bacteria. As the phagocytes start working, this means that the non-specific immunity has used the cellular component of the body defense from microbes and bacteria. The phagocytes express cell surface receptors that can bind and respond to common molecular patterns expressed on the surface of invaliding microbes (Coico, et al., 2003). In such a way, the non-specific immunity can protect the body from penetration, colonization, and spread of microbes throughout the body.
The specific immunity adapts itself to each new disease or bacteria that threaten to the health of humans, when specific immune components encounter a pathogen bacteria or disease. In response to such encounter the specific immunity generates pathogen-specific immunity. At this point, it is worth mentioning the fact that the specific immunity is divided into naturally acquired immunity and artificially acquired immunity. The naturally acquired immunity emerges when the contact with a disease causing agent occurs non-deliberately. In contrast, the artificially acquired immunity occurs when a disease causing agent confronts the immune system deliberately. As a rule, this occurs after a vaccination or other deliberate actions. The specific immunity is different from the non-specific immunity because it is acquired in the course of the development of human body and its immune system. Moreover, the specific immune system elaborates antigen or antibodies that oppose to specific disease or, to put it more precisely, disease causing agent. Instead, the non-specific immunity represents a complex of antigen that protects human body from numerous diseases and health problems.
However, I did not have much time to spend in the lung and to consider how the immune system of human body works. I had to move on. So, I continued my trip and I departed from the alveolar membrane further to trachea. After trachea, I entered epiglotis and moved further till I reached the nose and finally liberate myself from the human body.
In fact, this was probably the most unusual and unexpected trip that I have ever had. However, this trip helped me to view human body from within and that was quite a different view.
April, E. (2009). Clinical Anatomy, 3rd ed. Lippincott, Williams, and Wilkins.
Coico, R. et al. (2003). “Immunology: A Short Course. New York: Random House.
Maton, A. et al. (1993). Human Biology and Health. Englewood Cliffs, New Jersey, USA: Prentice Hall.
Rogan, M.P. et al. (October 2004). “Loss of microbicidal activity and increased formation of biofilm due to decreased lactoferrin activity in patients with cystic fibrosis”. The Journal of Infectious Diseases 190 (7): 1245–53.