Plant defense against herbivory which differ from one another in both functional groups, and in basic carbon skeletons. Monoterpenoids, continuing 2 isoprene units, are volatile essential oils such as citronella, limonene, menthol, camphor, and pinene. Diterpenoids, 4 isoprene units, are widely distributed in latex and resins, and can be quite toxic. Diterpenes are responsible for making "Rhododendron" leaves poisonous. Plant steroids and sterols are also produced from terpenoid precursors, including vitamin D, glycosides (such as digitalis) and saponins (which lyse red blood cells of herbivores). Phenolics, sometimes called "phenols", consist of an aromatic 6-carbon ring bonded to a hydroxy group. Some phenols have antiseptic
New Drug Application Review should complete within 6 months. The decision comes in a "Complete Response Letter". Biologics, such as vaccines and many recombinant proteins used in medical treatments are generally approved by FDA via a Biologic License Application (BLA), rather than an NDA. The manufacture of biologics is considered to differ fundamentally from that of less complex chemicals, requiring a somewhat different approval process. Generic drugs that have already been approved via an NDA submitted by another maker are approved via an Abbreviated New Drug Application (ANDA), which does not require all of the clinical trials normally required for a new drug