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Cholesterol

Teaching/Learning Cholesterol 2

Cholesterol is required to build and maintain cell membranes; it regulates membrane fluidity over a wide range of temperatures. The liver produces about 1 gram of Cholesterol per day through the bile, which contains cholesterol. Some research indicates that cholesterol may act as an antioxidant. Cholesterol also aids in the manufacture of bile (which is stored in the gallbladder and helps digest fats), and is also important for the metabolism of fat soluble vitamins, including vitamin A, D, E and K. It is the major precursor for synthesis of vitamin D and of the various steroid hormones ( which include cortisol and aldosterone in the adrenal glands, and the sex hormones progesterone, and various estrogen, testosterone and derivatives). It is the base structure for steroids. It also covers nerves in the form of myelin. This helps to conduct nerve impulses.
Most of the cholesterol in the body is synthesized by the body and some has dietary origin. Cholesterol is more abundant in tissues which either synthesize more or have more abundant densely-packed membranes, for example, the liver, spinal cord and brain. It plays a central role in many biochemical processes, such as the composition of cell membranes and the synthesis of steroid hormones. Since cholesterol is insoluble in blood, it is transported in the circulatory system within lipoprotein, complex spherical particles which have an exterior composed mainly of water-soluble proteins; fats and cholesterol are carried internally. There is a large range of lipoproteins within blood, generally called, from larger to smaller size: very low density lipoprotein which are the largest called very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), low density lipoprotein (LDL and high density lipoprotein (HDL). Large numbers of small dense LDL particles are strongly associated with the

Teaching/Learning Cholesterol 3
presence of atheromatous...