In biology and biochemistry, a lipid is a biomolecule that is soluble in nonpolar solvents. Non-polar solvents are hydrocarbons used to dissolve other hydrocarbon lipid molecules that do not dissolve in water, including fatty acids, waxes, sterols, fat-soluble vitamins (A, D, E, and K), monoglycerides, diglycerides, triglycerides, and phospholipids.

The functions of lipids include storing energy, signaling, and acting as structural components of cell membranes. Lipids have applications in the cosmetic and food industries as well as in nanotechnology.

Scientists sometimes define lipids as hydrophobic or amphiphilic small molecules; the amphiphilic nature of some lipids allows them to form structures such as vesicles, multilamellar/unilamellar liposomes, or membranes in an aqueous environment. Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups. Using this approach, lipids may be divided into eight categories: fatty acids, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from condensation of ketoacyl subunits); and sterol lipids and prenol lipids (derived from condensation of isoprene subunits).

Although the term "lipid" is sometimes used as a synonym for fats, fats are a subgroup of lipids called triglycerides. Lipids also encompass molecules such as fatty acids and their derivatives (including tri-, di-, monoglycerides, and phospholipids), as well as other sterol-containing metabolites such as cholesterol. Although humans and other mammals use various biosynthetic pathways both to break down and to synthesize lipids, some essential lipids can't be made this way and must be obtained from the diet. https://en.wikipedia.org/wiki/Lipid

noun: all the chemical processes by which cells produce the energy and substances necessary for life. Food is separated (dissociated) into the parts it is made up of to produce heat and energy, to repair tissues, and to help growth to happen.
noun: the organic processes in a cell or organism that are necessary for life
noun: the marked and rapid transformation of a larva into an adult that occurs in some animals

Metabolism ("change") is the set of life-sustaining chemical reactions in organisms. The three main purposes of metabolism are:

(1) the conversion of the energy in food to energy available to run cellular processes;
(2) the conversion of food to building blocks for proteins, lipids, nucleic acids, and some carbohydrates;
(3) and the elimination of metabolic wastes. [Metabolism]

Metabolic reactions may be categorized as catabolic – the breaking down of compounds (for example, of glucose to pyruvate by cellular respiration); or anabolic – the building up (synthesis) of compounds (such as proteins, carbohydrates, lipids, and nucleic acids). Usually, catabolism releases energy, and anabolism consumes energy. [Metabolism]

See Also

fatty acid
Fatty matter
fatty substance

Created by Dale Pond. Last Modification: Friday October 28, 2022 05:51:23 MDT by Dale Pond.