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.
Chapped lips (also cheilitis simplex or common cheilitis) are characterized by cracking, fissuring, and peeling of the skin of the lips, and are one of the most common types of cheilitis. While both lips may be affected, the lower lip is the most common site. There may also be burning or the formation of large, painful cracks when the lips are stretched. If chronic, cheilitis simplex can progress to crusting and bleeding.