Filler in textured paint works like spackling compound to fill the cracks, and dark, flat paint absorbs light to help conceal remaining blemishes. Be aware that dark colors will make your ceiling appear lower, so consider using very dark colors only in normally proportioned or narrow rooms.
In genetics, a promoter is a region of DNA that initiates transcription of a particular gene.
One dealing with the RNA Primer seen in DNA replication, and one dealing with the promoter seen in DNA transcription. The RNA Primer that is attracted to the DNA molecule (after it has been unzipped by DNA helicase) provides a place for the DNA Polymerase (the enzyme responsible for building the new strand of DNA) to start working.