Chemistry in its element podcast – cholesterol
Posted by Nina on Tue 28 Sep 2010Categories: Podcasts | 1 Comment
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In this week’s Chemistry in its element podcast, writer Hayley Birch shines a light on to the chemistry and medical uses of cholesterol
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Thu 7 Oct 2010 at 4:54 pm
Cholesterol is technically classified as a steroid, but is also classified as a lipid because it is soluble in fats. This crystalline substance is naturally found in the brain, nerves, liver, blood, and bile of humans. Despite all of the negative connotations, cholesterol is necessary for the proper functioning of the body. In fact your body can synthesise up to 1,500 milligrams of cholesterol a day (almost the amount in 10 eggs) using it for a number of crucial functions.
(1)It serves as the precursor for bile acids that are formed in the liver and secreted in the bile to facilitate intestinal fat digestion.
(2)In the gonad and adrenal cortex, cholesterol is used to synthesise all steroid hormones.
(3)In the skin, it is used to form vitamin D3, a reaction requiring ultraviolet sun radiation.
(4)Cholesterol is found in abundance in the nerve tissue, where it is a component of the myelin sheath that electrically insulates the axons (the part of the nerve cell specialising in conducting impulses over large distances to other nerve, muscle, or gland cells).
(5)Cholesterol helps minimise evaporation of body water as well as making the skin waterproof.
(6)Last but not least, cholesterol is a stabilising component of the actual membranes of cells and their organelles (all cells contain ‘miniorgans’ called organelles, each specialised to perform a particular function, which is why liver cells differ from brain cells, which themselves differ from blood cells).