| Symbol: Os; atomic weight: 190.2; atomic number: 76 |
| Symbol: Po; atomic weight: 210; atomic number: 84 |
lecithin lec·i·thin (lěs'ə-thĭn)
n.
Any of a group of phospholipids that on hydrolysis yield two fatty acid molecules and a molecule each of glycerophosphoric acid and choline. They are found in nervous tissue, especially myelin sheaths and egg yolk, and in the plasma membrane of plant and animal cells.
| lecithin (lěs'ə-thĭn) Pronunciation Key
A fatty substance present in most plant and animal tissues that is an important structural part of cell membranes, particularly in nervous tissue. It consists of a mixture of diglycerides of fatty acids (especially linoleic, palmitic, stearic, and oleic acid) linked to a phosphoric acid ester. Lecithin is used commercially in foods, cosmetics, paints, and plastics for its ability to form emulsions. |