Cardiovascular System

In Glogpedia

by JoeCrutchley10
Last updated 5 years ago

Human Anatomy

Toggle fullscreen Print glog
Cardiovascular System

There are 5 types of different blood vessels: arteries, arterioles, veins, venules and capillaries. Arteries: The arteries have a thick muscular wall, which are elastic to deal with blood flow at a high pressure, and have a small lumen. Its function is to transport blood to the body, always away from the heart and is responsible for redistribution of blood and blood pressure. Infact the wall of the left hand side of the heart is thicker to deal with the high blood pressure, leaving the Aorta and distributing blood to the whole body, this pressure will increase during exercise. It contains no valves, as the blood is at a high enough pressure already, needing no extra support. Arterioles: The Arteriols are just smaller branches of the arteries. Its fuction is to slow the blood pressure before it enters the capillaries. Just like the arteries they have no valves. The blood in them, is always flowing from the arteries to the capillaries.Veins: The veins have a much thinner muscular walls which are less elastic and have a large lumen. Its function is to only transport blood to the heart, never to the body. The veins contain valves, as blood is travelling at low pressure whilst in them, so it stops the blood from falling back and flowing in the wrong direction, causing the blood to clott. Muscle contraction can also assist in bringing blood back to the heart as veins are ound with muscles and when they contract the veins are constricted and the pressure increases, forcing the blood flow.Venules: The venules are just smaller branches of the veins. Its function is to collect the outflow blood from the capillaries, and pump the blood into the veins. Just like the veins, the venules have valves. Capillaries: The capillaries are only one cell thick, as diffusion is always occurring at them. They diffues oxygen and the CO2 in the muscles. They contain no valves. The blood travles at a steady pressure through muscles whilst in the capillaries. The blood flow is in the direction from the arteriols to the venules.

In the lungs, carbon dioxide is removed from the blood, and oxygen taken up by the haemoglobin in the red blood cells. The systemic circuit carries blood around the body to deliver the oxygen and returns de-oxygenated blood to the heart. Blood also carries nutrients and waste. These waste products are CO2.

Structure Of The Blood Vessels

The blood starts its journey through the heart, by entering the Vena Cava. This blood is currently de-oxygenated and is pumped into the Right Atrium from the Vena Cava. When the Right Atrium contracts, blood is pumped into the Right Ventricle via the Tricuspid Valve. The Right Ventricle then contracts, pumping the blood through the pulmonary valve into the pulmonary artery. The blood in the pulmonary artery is then taken to the lungs, where it collects oxygen. It is then brought back to the heart via the pulmomary vein. The oxygenated blood then re-enters the heart at the left atrium. The left atrium then contracts, pumping the blood into the left ventricle via the bicuspid valve. The left ventricle then contracts pumping the blood into the aorta, via the aortic valve. From the aorta, the oxygenated blood is pumped around the body, feeding the muscles with oxygen and nutrients

Delivery Of Oxygen And Nutrients

The Heart

Components Of Blood

There are four main components in the blood, Red Blood Cells, White Blood Cells, Platelets and Plasma.Red Blood Cells:Red blood cells start as immature cells in the bone marrow. Unlike many other cells, red blood cells have no nucleus and can easily change shape, helping them fit through the various blood vessels in your body. They contain the protein, haemogloblin which oxygen attaches to , delivering it to the muscles in the body. This supply is increased during exercise.White Blood Cells: White blood cells protect the body from infection, rapidly producing antibodies when presented with infections. They are much fewer in number than red blood cells, accounting for about 1 percent of your blood. Platelets: Platelets help the blood clotting process by gathering at the site of an injury, sticking to the lining of the injured blood vessel. Fibrin strands create a net that red blood cells gather within to cause a clot.Plasmas: Are a mixture of water, sugar, fat, protein, and salts. The main job of the plasma is to transport blood cells throughout your body along with nutrients, waste products, antibodies, clotting proteins, chemical messengers such as hormones, and proteins that help maintain the body's fluid balance.

Cardiovascular System

Our blood has 3 main functions: transport, protection and regulation. Transport: The blood transports gases, such as oxygen and cardbon dioxide. Delivering oxygen to the organs and muscles. The oxygen attaches to the haemoglobin in the red blood cells and through diffusion within the lungs at the alveoli is carried back to the heart and through the aorta is delivered to the working muscles, the demand for this delivery increases during exercise, therefore the rate of diffusion will also increase. Carbon dioxide and other waste bi products are also removed at the lungs through gaseous exchange.It also absorbs and transports glucose and nutrients from the digestive system to delivers them to sites around the body.Protection: The blood contains leukocytes and white blood cells, which fight off micro-organisms and cancer cells. The blood also contains platelets, which help the blood to clot, preventing large amounts of being lost. Fibrin strands gather at the sight of injury to create a net which gathers red blood cells which form a clot.Regulation: Our blood helps to regulate the pH levels by interacting with acids and alkali's.

Function Of The Blood

Thermoregulation is the process that allows the human body to maintain its core internal temperature. The state of having an even internal temperature is called homeostasis. All thermoregulation mechanisms are designed to return the body to homeostasis. Blood vessels supplying blood to the skin can swell or dilate, this is called vasodilation. This causes more heat to be carried by the blood to the skin, where it can be lost to the air. Blood vessels can shrink down again, this is called vasoconstriction. This reduces heat loss through the skin once the body’s temperature has returned to normal.



    There are no comments for this Glog.