Definitions of Wax, Steroids and Hormones

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 1. Wax:

Biological waxes are esters of long-chain (C14 to C36) saturated and unsaturated fatty acids with long-chain (C16 to C30) alcohols. Their melting points (60 to 100 _C) are generally higher than those of triacylglycerols.In plankton, the free-floating microorganism sat the bottom of the food chain for marine animals, and waxes are the chief storage form of metabolic fuel. Waxes also serve a diversity of other functions related to their water-repellent properties and their firm consistency. Certain skin glands of vertebrates secrete waxes to protect hair and skin and keep it pliable, lubricated, and waterproof. Birds, particularly waterfowl, secrete waxes from their preen glands to keep their feathers water-repellent. The shiny leaves of holly, rhododendrons, poison ivy, and many tropical plants are coated with a thick layer of waxes, which prevents excessive evaporation of water and protects against parasites. Biological waxes find a variety of applications in the pharmaceutical, cosmetic, and other industries. Lanolin (from lamb’s wool), beeswax carnauba wax (from a Brazilian palm tree), and wax extracted from spermaceti oil (from whales ;)

 2. Cholesterol:

Steroids, which are mostly of eukaryotic origin, are derivative of cyclopentanoperhydrophenanthrene the much maligned cholesterol. The most abundant
Steroid in animals is further classified as a sterol because of its C3-OH group and its branched aliphatic side chain of 8 to 10 carbon atoms at C17.Cholesterol is a major component of animal plasma membranes, where it is typically present at 30 to 40 mol %, and occurs in lesser amounts in the membranes of their sub cellular organelles. Its polar OH group gives it a weak amphiphilic character, whereas its fused ...

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...by various structural modifications
These groupings, therefore, appear in various combinations in anti-inflammatory steroids, many of which, however, lack the salt-retaining activity necessary for total adrenal replacement therapy. Cortisol analogs, such as dexamethasone, are used to treat many inflammatory and rheumatic diseases, to suppress the immune response in allergies and in organ transplantation,and to delay the progress of leukemia. They are also widely used for treating

 4. Biological significance of steroids:

That such diverse physiological functions and effects should be exhibited by
Steroids, all of which are synthesized by essentially the same central biosynthetic
Pathway is a remarkable example of biological economy. Most of these functions,
Especially those of a hormonal type, involve the transmission of biologically essential
Information.

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