Aortic Stenosis |Aortic stenosis is a narrowing of the aortic valve in the heart. This restricts the flow of blood through | |the valve. The left ventricle then needs to contract harder to pump blood into the aorta. Mild narrowing | |may not cause any symptoms. More severe narrowing can cause various symptoms and may lead to heart | |failure.
The left side (bicuspid) pumps oxygenated blood from the lungs to the body; the left chamber has a bigger muscular wall than the other chambers and is stronger, so it is able to pump the blood the whole of the body including the head and neck, as it is against the force of gravity. The two sides are separated by a septum. The heart also contains many veins and arteries. Blood is forced up into the Aorta (one of the large arteries) the Aorta splits into two separate parts, one goes up to the head and brain (upper part of the body) and one goes down (to the lower part of the body) Blood travelling around the body is called ‘systemic circulation’. The blood from these arteries feeds the organs and systems (cells & tissues).
The serous membrane secretes serous fluid into the space between the visceral and parietal layers that allows smooth movement between the layers, when the heart beats. The Myocardium: The myocardium is the middle layer of the heart and is composed of specialised muscle tissue called as the cardiac muscle, on which the circulation of blood depends. It varies in thickness, being thickest in the left ventricle, thinner in the right ventricle and thinnest in the artrium. The Endocardium: The endocardium forms the inner linging of the heart is a thin, smooth, glistening membrane consisting of flattened epithelial cells which is continuous with the valves and with the lining of the blood
Describe the effect that radius changes have on the laminar flow of a fluid. The larger radius, the greater laminar flow. This is due to more room inside of the vessel for blood to travel. 4. Why do you think the plot was not linear?
The normal function of the heart. The heart is a muscular pump in the centre of the chest that beats continuously and rhythmically to send blood to the lungs and the rest of the body. The heart muscle is supplied with oxygen and nutrients by two coronary arteries. Inside the heart there are four chambers. A thick central muscular wall, the septum, divides the heart into right and left halves.
Hemorrhagic stroke occurs when a blood vessel located in the brain starts to either leak or rupture. This is usually caused by high blood pressure and weakened walls of the vessel caused by an aneurysm. There are two types of hemorrhagic stroke, intracerebral and subarachnoid. An intracerebral hemorrhage is when an artery in the interior of the brain bursts and the blood moves into the surrounding area causing damage. In a subarachnoid hemorrhage, a blood vessel also bursts, but instead of being on the interior, the vessel is located near the surface of the brain.
The muscle is made from bundles of muscle fibers. The muscle fibers are made up of bundles of myofibrils and the myofibrils are made from many sarcomeres that are positioned end-to-end. They have a striated look due to the light I-bands and dark A-bands. Type I Fibres These fibres, also called slow twitch or slow oxidative fibres, contain large amounts of myoglobin (location where oxygen is stored), many mitochondria and many blood capillaries therefore these fibers are red in color. This fiber type relies on aerobic metabolism.
The heart is the pump that pushes the blood around the body. It is about the size of a clenched fist and sits in the centre of your chest behind your rib cage and sternum. The heart is surrounded by a number of vessels that carry blood either towards the heart or away from the heart. The blood carried by the vessel can either
The wave passes to the atrioventricular node where it is passed down the septum down specialised fibres known as the bundle of His. This occurs after a short delay to allow all the blood to flow from the atria to the ventricles. This wave passes down the bundle of His to the Apex of the heart where the Ventricles contract upward, pumping blood out of the ventricles into the pulmonary artery and aorta through the semilunar valves. Here the blood is then passed round the body where it
Pressure waves travel throughout the blood vessels, which can be felt by the further movement of the blood. When the heart contract, blood is expelled into the aorta and the aorta stretches. At this point the wave of distention is most distinct, but comparatively slow-moving. As it travels towards the peripheral blood vessels, it progressively diminishes and becomes faster. In the large arterial branches, its velocity is 7 to 10 m/s; in the small arteries, it is 15 to 35 m/s.