The Cardiovascular System Essay

William Li mentions the blood vessels in his talk. Human’s body is literally packed with them. The smallest blood vessels are called capillaries, it is the vessels of life and are feeding cancer cells, bringing oxygen and nutrients. Also, it can be the vessels of death. We have got nineteen million of them in our bodies. Blood vessels are adapt our bodies no matter where they grow in our bodies.

One of the most important systems in the body, keeping it alive, is the cardiovascular system. As a part of the circulatory system, the cardiovascular system pumps blood throughout the body through a network of many arteries and veins, providing it with nutrients and oxygen. Also, the cardiovascular fights infections and disease in the body and creates blood cells. Never the less, blood acts as a filtration system for the body and removes waste, cell debris, or bacteria from the bloodstream.

Veins are made up of more elastic tissue and less smooth muscle and carry blood to the heart from the body. The heart wall has three layers that surround the heart. The outer most layer is the epicardium, middle layer is the myocardium, inner layer is the endocardium.

I found the differences between arteries and veins are their functions they provide to the heart as well as their structure. Arteries transfers blood away from the heart into the periphery resulting in the pressure of the blood in the arteries being high. Where as, the veins transfer blood towards the heart. Arteries carry oxygenated blood distributing it in the periphery as the pulmonary artery moves deoxygenated blood into the lungs for purification. The wall of an artery consists of three layers machining it thicker than veins. The elasticity within the layers of the muscle allows arteries to handle great pressures of blood within it. The thickest layer is known as tunica media as the other two are recognized as tunica externa, and tunica interna. The vein obtains blood from the periphery and carries it towards the heart. Veins are known to carry deoxygenated blood and transfers it the heart for purification. The pulmonary vein is known to carry oxygenated blood. However, there are semilunar valves found within the vein that does not allow retrograde flow of blood in preventing blood to flow in the opposite direction. Veins are thinner when compared to arteries consisting of thin elastic muscle layers with one thick layer being the tunica adventitia. Arteries consist of: carrying oxygenated blood expect for the pulmonary artery; deeply found in the body; thick walled and

Blood contains nutrients from the foods you eat and oxygen from the air you breathe. It also

Oxygen and nutrients the body requires for function are pumped around this complex network of blood vessels by the heart. At roughly the size of a human fist, the heart is a four-chambered muscle and performs two functions of circulation simultaneously and continuously. Systemic and pulmonary circulation. The heart is made up from three separate layers of cardiac tissue; the outer layer called the pericardium, which is a double sac-like outer covering with serous fluid inside to keep the middle layer, the myocardium from adhering to the outer layer. This middle layer of the heart is the heart muscle which is thicker on the left side, to aid with the pressure needed to sustain systemic circulation. The inner layer of the heart is the endocardium. It’s lining is smooth to help prevent the blood which circulates around the inside of the heart from clotting. The heart is the human body’s in-built pacemaker, and the electrical signals sent through the it cause the heart to contract and relax. This process is triggered by the autonomic nervous system and the contraction and relaxing cycle is

Our blood is made up of several cells and plasma such as erythrocytes, red cells, that contain hemoglobin, leukocytes, known as white cells, that help the body fight the prevention of bacteria and infection, and lastly thrombocytes, platelets that aid in the formation of blood clotting by discharging various protein substances when one is injured. In addition, oxygenated blood is carried away from the heart through arteries, thick hollow tubes which are elastic, allowing them to dilate and constrict as blood is forced down. When arteries become smaller through re-branching, they become arterioles that feed capillaries. In fact, there are 3 types of capillaries, continuous, which allow small molecules to pass through, fenestrated, involving porous endothelial cells allowing small molecules and limited amounts of protein to diffuse, and discontinuous, which are the most flexible in allowing proteins and blood cells to pass through.

Cells take oxygen from the blood and thrust out the de-oxygenated blood. Now the de-oxygenated blood has to be sent back to the heart for the blood to be refreshed with oxygen and nutrients. Veins are the blood vessels that carry the blood, rich in waste content and low in oxygen content back to the heart (http://www.fairview.org/fv/groups/internet/documents/web_content/pdf_pad_screening.pdf, ). The main function of veins is to carry blood back to the heart. Veins are not muscular and are less flexible when compared to arteries (PVD). Unlike arteries, veins contains one way valves (unidirectional valves) that prevent the blood from flowing back, thus fighting against the gravity and allows blood flow only towards the heart. Valves have two

Arteries carry blood away from the heart and veins carry blood to the heart. Arteries are thicker than veins because it need to withstand the high pressure of the outflow of blood from the heart. In other words, the flow of blood from the heart is at high pressure to reach all the parts of the body quickly. The two exceptions are the pulmonary artery and the pulmonary vein. The pulmonary artery is carries deoxygenated blood but all the other arteries carry oxygenated blood and the pulmonary vein carries oxygenated blood but all the other veins carry deoxygenated blood.

Blood is one of the most vital components of the human body. The blood carries many functions such as to supply oxygen to the bodies tissues, remove metabolic waste products, regulate our core temperature as well as fighting infection and foreign bodies (Glover, 1997). The cardiovascular system is composed of the heart and its vessels. The heart is an involuntary muscle which receives blood to the atrias, which is then pumped via the ventricles. The vessels are composed of three main types. Arteries, veins and capillaries; all which transport blood throughout the entirety of the body. The constant action of both the vessels and heart ensure that the body receives a continuous supply of blood, keeping us within our homeostatic limits.

Veins, arteries and capillaries are the delivery routes of the heart which allow blood to be distributed to the body and organs. Moreover, where gas exchange takes place. Arteries carry oxygenated blood away from the heart to the systemic circulation and deliver oxygen-rich blood to the body whereas veins carry de-oxygenated blood from capillary beds towards the heart to get oxygenated (Marieb & Hoehn, 2013). For gas exchange the capillaries are in the lungs. Gas exchange occurs when O2 from the lungs to the bloodstream via the capillaries; at the same time CO2 passes from the bloodstream to the lungs. The Capillaries are located in the lungs within the muscles. Capillaries transport oxygen through its walls and diffuse into the tissue.

veins to the tissues of the body. These walls do not let out blood but

Blood vessels are extremely important part of our bodies. In fact there are so many of them that if we have to measure their length it would reach 60,000 miles in the body of an adult. The smallest vessels are known as capillaries. They can

The hearts role is to pump oxygenated blood to every cell in the body by having a continuous beat. Throughout time the heart has created mystery, however current technology has solved most of the mystery, there still remains an enchantment and eagerness to learn more.

The arteries are thicker and more elastic because of the fast pumping of blood that leaves the heart to other organs to the body, as where the veins are small due to the low blood flow because of the slow movement from the capillaries to the veins not like the forceful pumping from the heart to the arteries to the rest of the body. The Oxygenated blood goes through the arteries except the pulmonary arteries. Then Deoxygenated blood goes through the veins except the pulmonary veins. The lumen of the artery is narrow, were as the lumen of the veins is wider. There are not valves in the arteries, were as the valves are present in veins. In the arteries, endothelial cells of tunica intima are more long then wider, and have more elastic membrane that is more developed. Then the Tunica media is more muscular, and the tunica extrema is not as developed. In veins, the endothelial cells of tunica intima are not as long and have more elastic membrane then being developed. The Tunica media is less muscular were the tunica extrema is more developed. Arteries are deep within and the veins are more superficial. Capillaries are microscopic vessels; they carry blood from the arterioles then go to the small veins or venules. The wall of the capillary made up of a