Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
The CV System Explained
Transcript of The CV System Explained
The Cardio-Vascular System
Jordan Taylor Welcome; in this presentation i will be describing and explaining the structures and functions of the cardiovascular system. The Heart and its Structure Atria; The right atrium and left atrium (atria) are the upper chambers of the heart. They recieve blood returning to the heart from either the body or the lungs. Ventricles; The right and left ventricle are the pumping chambers of the heart. the right ventricle pumps blood to the pulmonary circulation for the lungs and the left ventricle pumps blood to the systematic circulation of the body. The wall of the left ventricle is a lot thicker than the wall of the right ventricle. This is because a lot more pressure is required to pump blood from the heart to the farthest body tissues. The right pulmonary pump only needs to pump blood as far as the lungs. Bicuspid Valve; The bicuspid valve allows blood to flow in one direction only, from the left atrium to the left ventricle. The valves prevent the backward flow of blood. Valves are actually flaps that act as one-way inlets for blood coming into a ventricle and one-way outlets for blood leaving a ventricle. Each valve has three flaps , except the mitral valve, which only has two flaps. Tricuspid Valve;; The tricuspid valve allows blood to flow in one direction only, from the right atrium to the right ventricle. The aortic valve prevents backflow into the aorta into the left ventricle. This may occur due to the low pressure and speed of the blood passing through. Aorta; The aorta is the body's main artery. It carries oxygenated blood to all parts of the body except the lungs. Vena Cava (Superior); The superior vena cava is a vein that recieves deoxygenated blood from the upper body to empty into the right atrium. Pulmonary vein; The pulmonary veins carry oxygenated blood from the lungs to the left atrium. Vena Cava (Inferior); The inferior vena cava is a vein that recieves deoxygenated blood from the lower body to empty into the right atrium. The Blood Vessels and their Structure Arterioles; Arterioles mostly share the same properties as arteries. This is because they are strong, have a relatively thick wall for their size, and contain a high percentage of smooth muscle. The increased amount of smooth muscle that is found in arterioles gives them extra strength and elasticity to deal with the surges of blood from the heart. Veins; Veins are similar to arteries but, because they transport blood at a lower pressure, they are not as strong as arteries. Veins have three layers: an outer layer of tissue, muscle in the middle, and a smooth inner layer of epithelial cells, just like that of arteries. However, the veins layers are thinner, containing less tissue. When blood pooline occurs, the veins are forced to contract to force the slow flowing blood through the vein so a clog isnt created and thatthe blood can be pushed back into a faster flow. Veins merely collect blood after it passes through the capillaries; the circulation is driven by valves inside the veins, rather than by the pumping of the heart, which is the reason veins are thinner than arteries. Venuoles; Venuoles are small vessels that branch from the veins, and are also linked to the capillaries. The Venuoles drain the deoxygenated blood from the capillaries and then carry the blood to the veins, where the veins then lead the blood back to the heart. Venules link the capillaries to the veins when blood is being transported back to the heart and lungs. A vein is much larger than a venule and can carry a much higher volume of blood. Many venules will join with a single vein to transport the blood. Most of the blood that is transported by the venules is deoxygenated blood. This means that the blood passed through various tissues and organs within the body and oxygen has passed from the blood into the cells of the body. The blood must now travel back to the lungs so it can pick up more oxygen to take back out to the body. Capillaries; Unlike the arteries and veins, capillaries are very thin and fragile. Due to this blood cells can only pass through them in single file and the exchange of oxygen and carbon dioxide takes place through the thin capillary wall. This is called gaseous exchnage. This layer is so thin that molecules such as oxygen, water and lipids can pass through them by diffusion and enter the tissues. Waste products such as carbon dioxide and urea can diffuse back into the blood to be carried away for removal from the body. Capillaries are so small the red blood cells need to partially fold into bullet-like shapes in order to pass through them in single file. Nutrients such as glucose etc. help the body in getting its energy as it is exchanged throught the capillaries to serge around the body. Arteries; An artery is an elastic blood vessel that transports blood away from the heart. There are two main types of arteries of which are the pulmonary arteries and systemic arteries. The arteries have three layers of which include the reason of the arteries elascticity. The Tunica Adventitia - the strong outer covering of arteries and veins. It is composed of connective tissue as well as collagen and elastic fibers. These fibers allow the arteries and veins to stretch to prevent overexpansion due to the pressure that is exerted on the walls by blood flow. The Tunica Media - the middle layer of the walls of arteries and veins. It is composed of smooth muscle and elastic fibers. This layer is thicker in arteries than in veins. The Tunica Intima - the inner layer of arteries and veins. In arteries this layer is composed of an elastic membrane lining and smooth endothelium (special type of epithelial tissue) that is covered by elastic tissues. Thanks! Any Questions The Function Of the Cardio-Vascular System The Delivery of Oxygen and Nutrients; The cardiovascular system supplies oxygen and nutrients to the body tissues through the bloodstream. these nutrients include, primarily oxygen and energy in the form of sugar/glucose. these nutrients are supplied through the blood celluarly. The Aortic Valve; Clotting; The circulatory system carries waste products from the tissues to the kidneys and liver and returns carbon dioxide from the tissues to the lungs. Most of the waste products in blood are breakdown products of protein metabolism and are carried by blood to organs of excretion for digestion. Waste products in blood include carbon dioxide, uric acid, creatine, bilrubin and ammonia. Carbon Dioxide is exchnaged during gaseous exchange which takes place within the capillaries 1 cell thick so that the carbon dioxide can be diffused. The Removal of Waste Products; Blood transports oxygen from the lungs to parts of the body that require it. It also transports metabolic waste from cells to areas of disposal. Oxygen in picked up in the lungs by hemoglobin which is found in red blood cells. The hemoglobin then transports the oxygen to cells that need it and when they release the oxygen, they pick up carbon dioxide. They then carry the carbon dioxide back to the lungs where most of it is exhaled. Nutrients are transported from the digestive system to tissues that require the nutrients aswell as waste products from the tissues to the liver so the can be detoxified and then to the kidneys for disposal. The main function of the respiratory system is gaseous exchange, of which is the process where Oxygen and Carbon Dioxide move between the lungs and blood. The blood in the capillaries surrounding the alveoli has a lower oxygen concentration than the air in the alveoli which has just been inhaled. Aswell as this both the alveoli and the capillaries have walls which are only one cell thick which allows gases to diffuse across them. Oxygen Transport; Human bodies have a number of strategies to fight infections or prevent them. The whole of our infection fighting apparatus is called the “immune system.” The human body’s immune system doesn’t just include white blood cells, which attempt to catch and destroy germs, but a variety of mechanisms that stop germs from creating infection. The gut and stomach contain mucus that can trap small numbers of foreign bacterial cells, keeping the body from becoming infected. Human bodies use a variety of acids in organs that create hostile environments for foreign cells. We also host helpful bacteria in our bodies that help keep other bacteria entering the body in check. Fighting Infection; A complex process in which white blood cells from solid clots. This is made possible by having a constant supply of blood through the cardiovascular system. As blood vessels become damaged, you bleed which washes out the dirt etc. and fills the wound, the blood vessels constrict & blood flow slows down. Platelets in the blood stick to collagen fibres that make up the vessel wall thus stopping the bleeding. Enzymes called clotting factors then trigger a chain of events including; Prothrombin converts to thrombin (this acts as an enzyme causing the plasma protein fibrinogen which forms long threads called fibrin). Fibrin threads wrap around the platelet plug forming a mesh template for a clot. The Clots mesh structure traps red blood cells and forms a clot. The red blood cells that are trapped on the outside of the clot dry out as the air reacts with the bloods iron, they then turn brownish red and a scab forms. Underneath the scab, blood vessels regenerate and repair the cells. Fibroblasts in the dermis create new cells. Scars provide extra strength to the skin that was deeply wounded which is made of interwoven collagen fibres with no hair follicles, nails or glands.. the feeling is lost because nerves have been damaged. Vasodilation; Vasoconstriction is the decrease in the diameter of the blood vessels. Contraction of invlountary muscle fibres in the vessel walls increases resistance to blood flow. This is linked to thermoregulation as it decreases blood flow in the tissues, so when a person is hot, vasoconstriction helps cool down the body as its part of thermoregulation. Vasoconstriction; Visodilation is an increase in the diameter of the blood vessels to decrease resistance to the flow of blood. This is linked to thermoregulation as it increases blood flow in the tissues, so when a person is cold, vasodilation helps warm up the body as its part of thermoregulation. The Function of the Blood; Blood contains; plasma, red blood cells, white blood cells and platelets. Some of the functions of blood include distribution, regulation, and the protection of wounds and injurys, that have made the skin bleed. The scars that are leftare made to create a strong protection barrier. Thermoregulation; The CV system is responsible for the distribution and redistribution of heat within the body to maintain thermal balance during exercise. In a healthy individual, the temperature of the body is 37°C. This thermoregulation is efficiently coordinated by the central nervous system as long as the temperature of the surroundings ranges between 20°C and 54°C. The heart is a complex organ, using four chambers, four valves and multiple blood vessels to provide blood to the body. The flow through the heart is also complex, with blood moving through the heart, then the lungs, before returning again to the heart. Blood returns to the heart from the body via two large blood vessels, called the superior vena cava and the inferior vena cava. This blood is deoxygenated, as it is returning from the body where oxygen is used. The blood first enters the right atrium, which then flows through the tricuspid valve into the right ventricle. When the heart beats, the ventricle pushes the blood through the pulmonic valve into the pulmonic artery. The pulmonary artery carries blood to the lungs where it collects oxygen, leaves the lungs and returns to the heart through the pulmonary vein. The blood enters the left atrium, and then descends through the bicuspid valve into the left ventricle. The left ventricle then pumps blood through the aortic valve, and into the aorta, the blood vessel that leads to the rest of the body providing oxygen to all of the muscles for them to work during any type of exercise. The Blood Flow Through The Heart Not partaking in Physical activity is one of the major risk factors for the occurrence of heart disease. Physical Exercise helps improve the heart's health, and can even reverse some heart disease risk factors, including the reduction of cholesterol.
Similar to all muscles the heart becomes stronger as a result of exercise this leads to it being able to pump more blood through the body with every beat and continue working at a maximum level, if needed, and with less strain. The resting heart rate of those who exercise is also lower, because less effort is needed to pump blood and as result leads to the person becoming more fit and a less chance of fatigue.
A person who exercises often and vigorously has the lowest risk for heart disease, but any amount of exercise is beneficial even if it just walking to shop each day for example. Light to moderate exercise is even beneficial in people with existing heart disease. The Effect on the Heart due to Physical Exercise The effects if their aren't valves within the heart; The valves purpose is to prevent the backwards flow of blood back into the heart. Without them the heart would pump blood out through the arteries and then be sucked back in as the heart relaxes. It would be like squeezing a bottle of water with a hose attached. The water would rise up the hose as the bottled was squeezed and fall back into the bottle as the bottle was released. so therefore it would prevent the heart from its funstion of providing ocygenated blood to muscles etc. and getting the deoxygenated blood to the lungs to be exhaled.