A series of heterocyclic compounds that are variously substituted in nature and are known also as purine bases. They include adenine and guanine, constituents of nucleic acids, as well as many alkaloids such as caffeine and theophylline. (DeCS/MESH. 2025. Purines. https://decs.bvsalud.org/en/ths/resource/?id=12123)
Terpenes are a class of natural products consisting of polyunsaturated hydrocarbon compounds with the formula (C5H8)n where n > 1. (Adapted from Wikipedia https://en.wikipedia.org/wiki/Terpene)
Note
Although sometimes used interchangeably with "terpenes", terpenoids (or isoprenoids) are modified terpenes that contain additional functional groups, usually oxygen-containing.
The record derives from WCSP which reports it as an accepted name (record 300481) with original publication details: Fl. Orient. 5: 304 1882. (http://www.theplantlist.org/tpl/record/kew-300481)
The process by which sperm is placed into a female’s uterus (intrauterine), or cervix (intracervical) using artificial means and with the intention of impregnating the female. (FAO. 2015. The Second Report on the State of the World’s Animal Genetic Resources for Food and Agriculture, edited by B.D. Scherf & D. Pilling. FAO Commission on Genetic Resources for Food and Agriculture Assessments. Rome (available at http://www.fao.org/3/a-i4787e/index.html).)
B horizons form below an O, A, or E horizon and they have undergone sufficient changes during soil genesis, such that the properties of their original parent material are no longer discernible. (https://en.wikipedia.org/wiki/Soil_horizon#B_horizon)
The active insecticidal constituent of Chrysanthemum cinerariifolium flowers. Pyrethrin I is the pyretholone ester of chrysanthemummonocarboxylic acid and pyrethrin II is the pyretholone ester of chrysanthemumdicarboxylic acid monomethyl ester (http://www.nlm.nih.gov/cgi/mesh/2010/MB_cgi?mode=&term=PYRETHRINS)
The 4-methanol form of vitamin B6 which is converted to pyridoxal phospate which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. (National Library of Medicine. MeSH (Medical Subject Headings), Pyridoxine MeSH Descriptor Data 2024, http://id.nlm.nih.gov/mesh/D011736)
Pyrus communis, commonly called European pear or common pear, is a parent of a large number of pear cultivars grown for fruit production. (Missouri Botanical Garden. Pyrus communis. https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=286400&isprofile=0&pt=7)
Pyruvate, the conjugate base of pyruvic acid, CH3COCOO−, is an intermediate in several metabolic pathways throughout the cell. Pyruvate is an important chemical compound in biochemistry. It is the output of the metabolism of glucose known as glycolysis. (https://en.wikipedia.org/wiki/Pyruvic_acid)
