A conjugated protein in whicha flavin nucleotide (FAD or FMN) is joinedto a protein component. Flavoproteins arefound in virtually all cells,acting as enzymesor as ELECTRON CARRIERS in the elec-tron-transport chain.由黄素核苷酸(FAD或FMN)和一种蛋白质成分相结合的结合蛋白质。黄素...[继续阅读]

    A polypeptide hormone,produced bythe B-cells of the islets of Langerhans in thepancreas,that controls the metabolism of glu-cose. Lack of insulin results in diabetes,butexcess insulin leads to coma.Its secretion is stimulated by high blood levels of gluco...[继续阅读]

    Aderivative of riboflavin (see flavoprotein) thatis a coenzyme in electron-transfer reactions.The reduced form,FADH2,is generated bythe Krebs cycle during aerobic respiration,and subsequently is oxidized to FAD bytransferring electrons to components of th...[继续阅读]

    A loose aggregation of blastomeresresulting from cleavage of the egg of mam-mals. It develops into the blastocyst.哺乳动物卵细胞分裂导致的卵裂球的松散集合。它发育为胚泡。...[继续阅读]

    A network of fibers within thecytoplasm of a cell that maintains its shape,enables movement of the cell,and providesanchorage and movement of its organelles. Itcomprises various elements,including MI-CROTUBULES,MICROFILAMENTS,andINTERMEDIATE FILAMENTS.See...[继续阅读]

    A large ameboid cell that canengulf,ingest,and destroy bacteria,dam-aged cells,and worn-out red blood cells.This process,called PHAGOCYTOSIS,is animportant part of the body defense againstdisease. Macrophages are found free (‘wan-dering’) in the tissues,i...[继续阅读]

    A belt of proteins that en-circles a dividing cell and contracts to pinchthe cell into two parts. Actin and myosinproteins assemble in the equatorial region ofa cell during mitosis,and organize to form acontractile ring. Following formation of thedaughter...[继续阅读]

    A nitrogenous base found in DNAand RNA. It is also a constituent of certaincoenzymes,for example NAD and FAD,and when combined with the sugar ribose it forms thenucleoside adenosine,found in AMP,ADP,andATP.Adenine is a PURINE,and contains a pairof fused r...[继续阅读]

    A three-dimensional re-gion (domain) of an ACTIVATOR-a type oftranscription factor that can activate genetranscription when the transcription factor isbound to the DNA molecule via another do-main (the DNA-binding domain). Activatorscan have more than one...[继续阅读]

    The occurrence of extra genesor segments of a chromosome in the genome.See chromosome mutation.基因组中额外的基因或染色体片段。参阅chromosome mutation。...[继续阅读]