Online Dictionary of Invertebrate Zoology: Complete Work - Best Text

Online Dictionary of Invertebrate Zoology 617hydrolysis of nucleic acids or nucleotides consisting of apurine or pyrimidine base linked to ribose or deoxyribose.nucleotide n. [L. dim. nucleus, kernel] Unit of the DNA andRNA molecules, including phosphoric acid, a purine orpyrimidine base, and a ribose.nucleus n.; pl. -lei [L. nucleus, kernel] 1. A spheroidal structurepresent in a cell containing the chromatin. 2. (MOLL:Gastropoda) The earliest-formed part of the shell, or operculum,of a protoconch.nudibranchiate a. [L. nudus, naked; branchiae, gills](BRACHIO) Having the gills uncovered and not protected bya shell or membrane in the brachial chamber.nudum n. [L. nudus, naked] (ARTHRO: Insecta) A small bare,sensitive portion of a butterfly antenna.nulliplex a. [L. nollus, none; plectare, to weave] A polyploidhaving all genes for a particular recessive character.numerical phenetics The hypothesis that relationship betweenorganisms can be determined by a calculation of anoverall, unweighted similarity value.numerical taxonomy Numerical evaluation of similarity betweentaxonomic units and grouping of these units intohigher taxa on the basis of their affinities; taxometrics. seetaxonomy.nuptial flight (ARTHRO: Insecta) In Hymenoptera, the matingflight of winged males and females.nurse cells 1. Cells of developing oocytes that provide materialfor further growth; trophocytes. 2. (ARTHRO: Insecta) Insome species, the nurse cells synthesize nucleic acids andpossibly protein and supply them to the oocyte via intercytoplasmicconnections. 3. (NEMATA) A specialized plantresponse to feeding sessile forms, characterized by specialfeeding cells around the nemas' head that are not subjectto necrosis; giant cells. 4. (PORIF) The archaeocytes.nutant a. [L. nutare, to nod] Nodding; drooping; having a tipbent horizontally.nutricial castration, castration nutriciale (ARTHRO: Insecta)In Hymenoptera, the condition of undeveloped gonads in