biol 4800 class 5 summaries

biol 4800 class 5 summaries - Brett Carlin Biol 4800...

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Brett Carlin Biol 4800 section 4 Class 5 Presentation Summaries Cholesterol and Cardiovascular Health Mark Covington Cholesterol is a lipid found in the cell membrane of all tissues and is transported in the blood plasma of all animals. It plays a central role in many biochemical processes such as the composition of cellular membranes and the synthesis of steroid hormones. Cholesterol is insoluble in blood and is transported through the body bound to lipoproteins in the circulatory system. The cell recognizes the Apo-B 100 on the surface of the LDL molecule, binds to it through the LDL-receptors on the exterior of the cell. The cell then brings the LDL particle containing the cholesterol bound to it inside the cell and degrades the complex in a lysosome. The resulting cholesterol is used for many of the cells needs. Cholesterol has many required functions in the body. It is more abundant in tissues which either synthesize more or have more abundant densely-packed membranes, for example the liver, spinal chord, and brain. Cholesterol is required to build and maintain cell membranes, while regulating membrane fluidity over a wide range of temperatures. Also, one of the most important functions of cholesterol is its support of the nervous system. Cholesterol is a vital component of the myelin sheath, which allows neurons to conduct impulses necessary to communicate with each other, and has been found to be the rate-limiting factor in the formation of synapses; the formation of which is necessary for learning and the recording of memories. Cholesterol not only helps guide the connecting parts of neurons to the right places but is necessary for their ability to grow from the start. Cholesterol is broken up into LDL and HDL cholesterol; depending on the molecular weight and size. High cholesterol occurs when you have too much LDL, or "bad" cholesterol. When you have high cholesterol, it can build up along the walls of your arteries. This buildup is called plaque. When too much plaque builds up, it can block the flow of blood. If an artery that supplies blood to your heart or to your brain is completely blocked, the result can be a stroke or a heart attack and could possibly lead to death. Most people can bring down their blood cholesterol levels without medication; by changing their diet and by becoming more active.   Certain foods can decrease your cholesterol levels just as much as other can increase them. Also, lowering cholesterol can help prevent heart attacks even if you already have heart disease.
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The cardiovascular system (or circulatory system) is an organ system that moves nutrients, gases, and wastes to and from cells, helps fight diseases, and helps stabilize body temperature and pH to maintain homeostasis. The main components of the human circulatory system are the heart, the blood, and the blood vessels. The most common cause of heart disease is a narrowing of or blockage in the coronary arteries supplying blood to the heart muscle itself. If your levels of cholesterol are too high, LDLs will leave extra cholesterol in the
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biol 4800 class 5 summaries - Brett Carlin Biol 4800...

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