Atherosclerosis is a cardiovascular disease of the walls of the artery that comes as a result of accumulation of fatty deposits on walls of the artery leading to an impairment of the flow of blood (Weber & Soehnlein, 2013). With in mind that cardiovascular diseases cause deaths and morbidity in several countries, atherosclerosis can be viewed as a serious disease particularly with regards to the ever increasing cases of obesity.
Notably, there is an apparent relationship between atherosclerosis and heart attack; atherosclerosis most commonly leads to heart attack. The understanding of the relationship between atherosclerosis and heart attack can be best understood with the understanding of how the heart functions. The main function of the heart is to pump blood to all parts the body. Pumping of blood by the heart is made possible by the help of heart muscles (cardiac muscles that contract and relax rhythmically thereby pumping the blood) which also depend on the same blood being pumped for oxygen. As mentioned above, atherosclerosis is the buildup of fatty deposits called plague in inside surfaces of the arterial wall (inclusive of the coronary arteries) (Schade, 2006). With time, the plaque might rapture the walls of the artery prompting the formation of blood clot at the point of the rapture. The buildup of blood clot at the point of the rapture might lead to total occlusion of the artery. Heart attack occurs when the total occlusion occurs in a coronary artery resulting into parts of the heart failing to get oxygen. Continued occlusion causes death of the affected parts of the blood, and this can lead to heart attack when the heart finally fails to functions totally (Schade, 2006).
There are significant structural and functional differences between arteries and veins. For instance, while arteries carry blood away from the heart, veins carry blood to the heart. Again, despite being more elastic compared to veins, all arteries, except the pulmonary artery, carry oxygenated blood while all veins (with the exception of the pulmonary vein) carry deoxygenated blood (Alter, 2004). It can also be noted that unlike veins which do not pulsate, arteries expand and contract rhythmically hence helping in the creation of the high pressure of blood flowing in them so that all parts (including distant body parts) supplied with blood. Difference in vascular compliance (a property of the vascular tissues that depends on the size of the vascular tissues and the distensibility of the vascular wall), as identified by Seifter, Sloane & Ratner (2006) is yet another significant difference that can be pointed out between arteries and veins. Noting that vascular compliance is the change in volume of the vessel are a result of the change in pressure vascular compliance is high when a large volume can be accommodated by a small pressure difference and is low when only a small volume can be accommodated by a large pressure difference (Seifter, Sloane & Ratner, 2006). In this regard, Seifter, Sloane & Ratner (2006) asserts that veins have high compliance when pressure is low while arteries have high compliance when pressure is high. From this statement, it can easily be pointed that blood in the arteries flow at higher pressure that blood in vein and in a similar manner, arteries have thicker walls than vein. Ideally, there are also significance differences between arteries and capillaries. Nonetheless, the differences between arteries and capillaries are almost similar to the differences between arteries and vein. The functions of arteries and veins can be drawn from the differences stated above. The major functions of all arteries (except pulmonary artery) is to supply the difference parts of the body with oxygenated while veins bring deoxygenate blood to the heart to be pumped back to the lungs for oxygenation.
Unlike molluscs and arthropods, vertebrates and some invertebrates have a closed circulatory system. Open circulatory system is characterized by the flow of blood in open spaces (called haemocoel) and the blood comes into direct contact with the cells allowing exchange of materials to take place by diffusion (Rastogi, 2001). Closed circulatory system, on the other hand, is characterized by the containment of blood in vessels hence exchange of material takes place across the walls of the capillaries (Rastogi, 2001). One advantage of the closed circulatory system over open circulatory system is that in the closed circulatory system, blood is supplied at a relatively high pressure hence more blood is pumped to various parts of the body in a shorter time (Rastogi, 2001). This is not the case in open circulatory system in which the blood does seem to reach different parts of the body after a prolonged period of time. Again, with the help of sphincters and musculatures present in the vessels used to supply blood in a closed circulatory system, it can be asserted that blood flow can easily be regulated in a closed circulatory system as opposed to open circulatory system in which there is no sphincters and musculatures to enable such a regulation (Rastogi, 2001).
Lymphatic and Circulatory System
There exists an association between the lymphatic system and the circulatory system. According to Chiras (2012), the lymphatic system is a meshwork of small vessels that almost resemble the capillaries. Pointedly, the lymphatic system compliments the circulatory system. The amount of intercellular fluid (carrying nutrients and oxygen) that flow out of the capillaries is always less than the amount that flows back into the capillaries. The lymphatic vessels which are equally highly permeable like the capillaries helps be refilling the capillaries with intercellular fluid (interstitial fluid) (Chiras, 2012). Just like the arteries, there are diseases that can lead to the blockade of the lymphatic vessels. Lymphedema is one such disease; the disease results from the blockade or damage of the lymphatic system. Ladas & Kelly (2012) contend that obesity, removal of a large number of lymph nodes and cancer treatment are some of risk factors associated with the lymphedema.
References
Alter, M. J. (2004). Science of flexibility. Champaign: Human Kinetics.
Chiras, D. D. (2012). Human biology. Sudbury, MA: Jones & Bartlett Learning.
Ladas, E. J., & Kelly, K. (2012). Integrative Strategies for Cancer Patients: A Practical Resource for Managing the Side Effects of Cancer Therapy. Singapore: World Scientific.
Rastogi, V. B. (2001). Modern Biology Vol II. New Delhi, India: Pitambar Publishing Company (P) Limited.
Schade, J. P. (2006). The complete encyclopedia of medicine & health. Franklin Park, NJ: Foreign Media Books.
Seifter, J., Sloane, D., & Ratner, A. (2006). Concepts in medical physiology. Philadelphia, PA: Lippincott Williams & Wilkins.
Weber, C., & Soehnlein, O. (2013). Atherosclerosis: Treatment and Prevention. Boca Raton : CRC Press.
