Oxygen Transport in a Human Body - Essay Example

Introduction: Oxygen (O2) happens to be one of the vital elements when it comes to the aspect of life sustenance and supply of metabolic processes within the human body. Oxygen not only offers us with life, but also plays a greater role of destroying harmful bacterial substances in our entire bodies without affecting beneficial bacterial content that we are in need of. Therefore, chemical engineering hence treat the body as a chemical plant with inputs such as (food, air and water), as well as outputs such as (air, urine and feces). Moreover, some of the two remarkable organisms within the circulatory system are often the blood vessels and the heart. For such a reason, chemical engineering based on this models treats the circulatory system as a chemical process, with the heart as an ultimate pump and blood vessels acting as pipes. However, the body which is termed as a chemical plant in this perspective since it is accorded with both the output and input systems and allows us to use mathematical equation for modeling oxygen transport. On the other hand, it is of great value to know the term diffusion and convection and towards learning and calculation of the rate of oxygen transport within a human body. This convection is much more dominant in the larger blood vessel like arteries. Also, diffusion occurs more likely within dominant small blood vessel including veins and capillaries. There are two major equations that are often used for determination of oxygen transport system. They are stated as follows; Overall flux equation that describes flow through pumps and pipes: NA,z = YA ( NA,Z + NB,Z ) – DA,T∇c Convection Diffusion Fick’s law that describes the diffusion fluid down the concentration gradient: JA,z = −DA,z∇c Oxygen transport in a human body : The entire breathing system often begins begin from the nose towards lungs, before finally dissolving in the water lining composed of alveoli. Oxygen hence clings into the red blood cells as they bypass through the alveoli capillaries. The Circulatory System: The entire circulatory system is mainly responsible for the transport of substances throughout the body. It transports water, oxygen and nutrients to billions of the body cells as well as carrying away of wastes that includes carbon dioxide produced by the body during the entire excretion process. It one of the most amazing highway that revolves through an individual’s entire body while connecting all the available body cells. The heart, lungs, and blood vessels work together towards forming the circular segment of the entire circulatory system. The heart plays a distinct role of pumping blood and keeping of the blood flow throughout an individual’s body. Blood vessels assist in transportation of blood from the heart to all the destined places. Their main role is to the aspect of oxygen transportation from outside into the entire bloodstream, and the release of carbon dioxide from bloodstream into the ultimate outlet regions. The blood vessels: Blood vessels usually operate as pipes within a human body. Blood vessels are in three main categories that include; veins, capillaries, and arteries. During the process of blood circulation, arteries often carry blood away from the heart. Capillaries link arteries towards veins. Finally, veins carry blood back to the heart. The heart initially pumps blood through arteries before the main artery transports blood towards other branches such that each body region receives oxygen that is rich with blood. Veins often receive blood from capillaries after carbon dioxide and oxygen exchange has taken place. Therefore, veins transport waste-rich blood back to the heart and lungs. The capillaries connect arteries with veins, and plays essential role of transporting oxygen concentrated with red blood cells. It starts exchanging carbon dioxide and oxygen through thinner capillary wall. Red blood cells beneath the capillary vessels release oxygen, which hence passes through that wall into the entire surrounding tissue. The tissue then releases waste products, such as carbon dioxide, which bypasses through that wall into the red blood cells. The blood: In the entire human body, blood is usually the most essential substance, and is often the base media for oxygen transport throughout the body tissues. It contains white blood cells, red blood cells, water, nutrient, O2, as well as the waste products emanating from the body cells. It transports oxygen way back from the lung towards the body tissue as well as carbon dioxide from the body tissue into the lungs. Red blood cells constantly travel through an individual’s body hence removing waste and delivering oxygen. They take oxygen into lungs and release it in the process of squeezing through the body with the help of capillaries. It contains a chemical known as hemoglobin, which often helps in the aspect of oxygen attraction since it can hold four oxygen units. As blood goes through lungs, oxygen molecules get attached to hemoglobin. As they pass through bodys tissue, hemoglobin releases oxygen towards the cells. Empty hemoglobin molecules hence bond with tissues carbon dioxide or any other waste while transporting it away. However, Plasma often takes 55% of the blood volume and it distinct for being a thicker liquid. It is the ultimate container whereby blood cells travel through. It carries both the blood cells as well as the nutrients, clotting proteins and waste products. Diffusivity: DA,B Diffusion coefficient is a function that depends on the atomic and size of the makeup of the diffusing molecules and media properties. Therefore, the smaller compound has got the quickest passing rate through the biological system such as O2, and the larger the molecule the lower the rate of diffusion. Convection and diffusion: Convention refers to the mass of material or substance transport between the moving fluid and the boundary surface, while diffusion refers to a net molecular movement towards the direction of low concentration. Also, convection is often dominant in larger blood vessels, as diffusion is also dominant in smaller blood vessels. The overall flux equation under the conviction terms that we account for oxygen flow rate due to the flowing blood, can be clearly represented in the blood flow direction. NA,z = CA + VA,z During convection, concentration of the oxygen transportation within the blood vessels often assumes a constant rate, while in smaller vessels oxygen diffuses outride the veins into the entire surrounding tissues thus resulting in concentration decrees. Moreover, diffusion rapidly takes place outside the capillarity wall whereby concentration profiles entirely exist. Furthermore, convection occurs inside the vessel whereby the concentration of dissolved O2 is assumed as being a constant. NA,z = YA ( NA,Z + NB,Z ) – DA,z∇c Decrease in the vessel’s diameter, leads towards the convection becoming less dominant, as well as significant increase in diffusion. Also, various boundary conditions have also been put into consideration for the geometries: Slab At Z=0, and Z=L, C=Cb=0.002068 Cylinder and Sphere At r=0, and r=rout, c=cb=0.002068 Boundary conditions are essentially intuitive because the core concentration at does not change as well as the oxygen concentration especially at the geometry edge that is equal to the concentration of the bulk plasma. Bio-hybrid Devices: This are the developed methods of replacing damaged organs functions through cell combination with the synthetic materials (Polymer), so as to be capable of secreting the required protein for the operations of specific organs, and also help in being protective from killing by recipient’s immune system. In simple terms, it makes sure that the body is ready to replace and accept the implant cells without rejection from the immune system. Bio-hybrid devices are used for prevention of diseases including diabetes and liver failure. For diabetes the bio-hybrid artificial pancreas provides a solution to several problems involved in insulin transplantation and tissue production in diabetic patients. However, the bio-hybrid device is also preventing liver failure; bio-hybrid artificial liver (BAL) system is a man-made extracorporeal supportive device that represents essential therapeutic strategies for liver failure patients. Generally, BAL system is comprised of functional liver cells that are supported by artificial cell culture substances. BAL system operates as a patients’ bridge until donor organ is availed for transplantation or liver regeneration. There are a number of variations between intravascular and extra vascular concepts as substantiated below. Intravascular bio-hybrid devices are often placed within larger blood vessels, and cells implantation outside blood supply unit. In the intravascular bio-hybrid device oxygen diffuses outward from the capillary into the tissue. On the other hand, in extra vascular format, devices are often placed outside vascular compartment. Also, the cells are encapsulated in tissue, surrounded by the blood vessels. The main issue involving blood vessel growth allows for adequate oxygen transfer within such a device. Conclusion: Through utilization of excel assumed figures and values for r/z towards polymer computation for each cylindrical, flat slab and spherical shapes; the values that came up were plot in a graph. The plot shows the entire relationship between concentration and r. Sphere has got the greatest volume against the surface ratio thus allowing for efficient O2 transport throughout the device, and more efficient and effective O2 delivery to the entire cells in the polymer device. For such a reason, liver cells will possibly be implanted successfully into the spherical device. Read More