Organic compound that is an important component of lipids in plants, animals, and microorganisms. Fatty acids are carboxylic acids with a long hydrocarbon chain, usually straight, as the fourth substituent group on the carboxyl (singlehorzbondCOOH) group (see functional group) that makes the molecule an acid. If the carbon-to-carbon bonds (see bonding) in that chain are all single, the fatty acid is saturated; artificial saturation is called hydrogenation. A fatty acid with one double bond is monounsaturated; one with more is polyunsaturated. These are more reactive chemically. Most unsaturated fats are liquid at room temperature, so food manufacturers hydrogenate them to make them solid (see margarine). A high level of saturated fatty acids in the diet raises blood cholesterol levels. A few fatty acids have branched chains. Others (e.g., prostaglandins) contain ring structures. Fatty acids in nature are always combined, usually with glycerol as triglycerides in fats. Oleic acid (unsaturated, with 18 carbon atoms) is almost half of human fat and is abundant in such oils as olive, palm, and peanut. Most animals, including mammals, cannot synthesize some unsaturated “essential” fatty acids; humans need linoleic, linolenic, and arachidonic acids in their diet.
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Fatty's Tintype Tangle is a 1915 comedy short film. A man, tired of his mother-in-law's henpecking, leaves home in anger and sits on a park bench, where a photographer takes a picture of him sitting next to a married woman, whose husband is not pleased.
The movie stars Roscoe 'Fatty' Arbuckle, Louise Fazenda, Edgar Kennedy, Minta Durfee and Frank Hayes. The film was directed by Arbuckle and features a spectacular sequence of Arbuckle walking on power lines.
The film has been selected for preservation in the United States National Film Registry.