chromosome

noun chro·mo·some \ ˈkrō-mə-ˌsōm , -ˌzōm \
|Updated on: 12 Jun 2018

Definition of chromosome

: any of the rod-shaped or threadlike DNA-containing structures of cellular organisms that are located in the nucleus of eukaryotes, are usually ring-shaped in prokaryotes (such as bacteria), and contain all or most of the genes of the organism; also : the genetic material of a virus — compare chromatin

chromosomal

play \ˌkrō-mə-ˈsō-məl, -ˈzō-\ adjective

chromosomally

play \-mə-lē\ adverb

Recent Examples of chromosome from the Web

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Origin and Etymology of chromosome

borrowed from German Chromosom, from chromo- chromo- + -som 3-some
Note: The term Chromosom was first suggested by the German anatomist Heinrich Wilhelm Gottfried von Waldeyer-Hartz in "Ueber Karyokinese und ihre Beziehungen zu den Befruchtungsvorgängen," Archiv für mikroskopische Anatomie, Band 23 (1888), p. 27: "In ester Linier möchte ich mir jedoch den Vorschlag erlauben, diejenigen Dinge, welche soeben mit Boveri als 'chromatische Elemente' bezeichnet wurden, an denen sich einer der wichtigsten Akten der Karyokinese, die Flemming'sche Längsteilung vollzieht, mit einem besonderen terminus technicus 'Chromosomen' zu belegen. Der Name 'primäre Schleifen' passt nicht, da wir bei weitem nicht immer eine Schleifenform für diese Dinge haben. 'Chromatische Elemente' ist zu lang. Andererseits sind sie so wichtig, dass ein besonderer kürzerer Name wünschenswerth erscheint. Plattne… gebraucht den Ausdruck 'Karyosomen'; da dieser aber zu sehr an Kernkörperchen erinnert, dürfte eine andere Bezeichnung vorzuziehen sein. Ist die von mir vorgeschlagene praktisch verwendbar, so wird sie sich wohl einbürgern, sonst möge sie bald der Vergessenheit anheimfallen." ("In the first place I must allow myself to suggest a new technical term, 'chromosomes,' for those things which have been designated by Boveri 'chromatic elements,' at which one of the most important acts of karyokinesis, Flemming's longitudinal splitting, is carried out. The name 'primary loops' is not suitable, since it is by no means the case that these things always have the form of a loop. 'Chromatic elements' is too long. On the other hand, they are so important that a special shorter name seems desirable. Plattner uses the expression 'karyosomes,' but as this too readily brings to mind nucleoli, another name is to be preferred. If the name I propose is serviceable, it will become customary, otherwise it will soon pass into oblivion.")

Other Genetics Terms


CHROMOSOME Defined for English Language Learners

chromosome

Definition of chromosome for English Language Learners

  • : the part of a cell that contains the genes which control how an animal or plant grows and what it becomes


CHROMOSOME Defined for Kids

chromosome

noun chro·mo·some \ ˈkrō-mə-ˌsōm \

Definition of chromosome for Students

: one of the rod-shaped or threadlike structures of a cell nucleus that contain genes and divide when the cell divides

Medical Dictionary

chromosome

noun chro·mo·some \ ˈkrō-mə-ˌsōm, -ˌzōm \

medical Definition of chromosome

: any of the usually linear bodies of the cell nucleus of eukaryotic organisms, the usually circular bodies of prokaryotic organisms (as bacteria), or especially in some schools of molecular biology the genomes of DNA viruses (as bacteriophages) that take up basophilic stains and contain most or all of the genes of the organism
  • both the chromosomes of cells and those of viruses can duplicate only in the complex environment of a living cell
  • —J. D. Watson
  • an episome, an element that may exist as a free circular plasmid, or that may become integrated into the bacterial chromosome as a linear sequence
  • —Benjamin Lewin

chromosomal

play \ˌkrō-mə-ˈsō-məl, -ˈzō-\ adjective

chromosomally

play \-mə-lē\ adverb

Illustration of chromosome

illustration of chromosome



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