DNA. complementary DNA (cDNA), copy DNA DNA transcribed from a specific RNA through the action of the enzyme reverse transcriptase. mitochondrial DNA (mtDNA) the DNA of the mitochondrial chromosome, existing in several thousand copies per cell and inherited exclusively from the mother.
Castor Oil. Castor oil is another good treatment for dry and chapped lips. Simply apply castor oil to your lips several times a day. You can also make a soothing treatment using one teaspoon of castor oil, one teaspoon of glycerin and a few drops of fresh lemon juice.
1 The juice from citrus fruits may cause both irritation as well as a sun sensitive allergy that looks like chapped lips. 2  Eating figs can result in a light allergy. 3  An ingredient known as phenyl salicylate (salol) used in lip care products may be your culprit.