Some polyps tend in time to develop a malignant clone of cells. All the members of a single species present in a defined area. PPM Parts per million. Precursor activation Predation Living by devouring other organisms. Primary transcript Primitive Similar to that occurring in the early evolutionary history of the structure or organism in question.
Producers start food chains .
Profundal zone Progesterone Progestin Any steroid that mimics the effects of progesterone . Sometimes spelled procaryote. Promoter Region of DNA, usually on the 5' side of a gene, that is needed for the initiation of the transcription of that gene. RNA polymerase and other transcription factors bind to the promoter. The sperm nucleus and egg nucleus within the fertilized egg before their fusion to form the diploid zygote nucleus.