![\"Quel](\"\/documents\/images\/histologie_articles\/ovaire\/lombric_cs_anterieure_ovaire_06-WEB.jpg\")
<\/p>\n
Voir l’image de plus grande taille<\/a><\/p>\n <\/p>\n Voir l’image l\u00e9gend\u00e9e<\/a><\/p>\n <\/p>\n L’image de la semaine 13-2019 provient de l’observation d’une coupe histologique \u00e0 l’objectif x40 du microscope photonique.<\/p>\n Elle repr\u00e9sente une portion triangulaire d’organe, contenant des unit\u00e9s de dimensions diverses semblant isol\u00e9es les unes des autres par de fines enveloppes. <\/p>\n Les cellules ont des dimensions diff\u00e9rentes en raison de l’abondance variable du cytoplasme, leurs noyaux apparaissant de tailles similaires quand ils sont visibles. Parall\u00e8lement, les contenus nucl\u00e9aires sont divers, la chromatine se pr\u00e9sentant sous forme d’amas ou de filaments plus ou moins \u00e9pais. Un tel organe, contenant des cellules de dimensions diverses et en cours de m\u00e9iose, est un ovaire. Il s’agit d’un ovaire de Lombric, \u00e9galement appel\u00e9 Ver de terre, appartenant au groupe des Ann\u00e9lides<\/a> oligoch\u00e8tes. <\/p>\n Chez le Lombric, l’ovaire est d\u00e9limit\u00e9 ext\u00e9rieurement par une enveloppe form\u00e9e d’une couche de cellules plates reposant sur une fine couche fibreuse. Elles d\u00e9terminent un \u00e9pith\u00e9lium<\/a> simple et pavimenteux associ\u00e9 \u00e0 du tissu conjonctif<\/a> fibreux. L’ensemble constitue la limite de la cavit\u00e9 c\u0153lomique<\/a>.<\/p>\n Chaque ovocyte est en outre entour\u00e9 d’une tunique fibreuse ainsi que de cellules plates. Qualifi\u00e9es de folliculaires, elles constituent un follicule au sein duquel est situ\u00e9 l’ovocyte. <\/p>\n <\/p>\n Pour en savoir plus, consulter :<\/p>\n • <\/span>les pages Premiers pas histologiques<\/a> de Codex virtualis (adresse : http:\/\/codexvirtualis.fr\/codex\/de-lorganisation-interne\/premiers-pas-histologiques)<\/p>\n • <\/span>Burkitt H.G., Young B., Heath J.W., 1993 \u2013 Histologie fonctionnelle Wheater. Arnette, 408p. Paris<\/p>\n • <\/span>Gorgees N. S. and Khalid V. A., 2017 – Histomorphology of the ovaries of the earthworm, Dendrobaena atheca<\/em> Cernosvitov (Annelida, Clitellata: Oligochaeta)<\/a>. Journal of Morphological Science, 34, 3 : 178-185 (adresse : https:\/\/www.thieme-connect.de\/products\/ejournals\/abstract\/10.4322\/jms.117817) • <\/span>Heusser S., Dupuy H.G., 2015 \u2013 Atlas biologie animale. Dunod, 220p. Paris<\/p>\n • <\/span>Leake L. D., 1975 \u2013 Comparative histology, an introduction to the microscopic structure of animals. Academic press, 738p. London, New York, San Francisco<\/p>\n • <\/span>Siekierska E., 2003 – The structure of the ovary and oogenesis in the earthworm, Dendrobaena veneta<\/em> (Annelida, Clitellata)<\/a>. Tissue & Cell, 35 : 252\u2013259 <\/p>\n Une citation \u00ab\u00a0Dans chaque vieux, il y a un jeune qui se demande ce qui s’est pass\u00e9.\u00a0\u00bb T. Pratchett Une image Voir l’image de plus grande taille Voir l’image l\u00e9gend\u00e9e L’image de la semaine 13-2019 provient de l’observation d’une coupe histologique \u00e0 l’objectif x40 du microscope photonique. Elle repr\u00e9sente une portion […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[47,14,23,22],"class_list":["post-11891","post","type-post","status-publish","format-standard","hentry","category-a-la-une","tag-annelide","tag-histologie","tag-observation","tag-physiologie"],"aioseo_notices":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts\/11891","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/comments?post=11891"}],"version-history":[{"count":8,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts\/11891\/revisions"}],"predecessor-version":[{"id":11904,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/posts\/11891\/revisions\/11904"}],"wp:attachment":[{"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/media?parent=11891"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/categories?post=11891"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/codexvirtualis.fr\/codex\/wp-json\/wp\/v2\/tags?post=11891"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nLa plupart comportent une sous-unit\u00e9 claire dans laquelle des ponctuations et des filaments sombres sont pr\u00e9sents. Elle est entour\u00e9e d’une couronne intens\u00e9ment color\u00e9e et granuleuse.
\nCette organisation est caract\u00e9ristique des <\/a>cellules<\/a> animales, la sous-unit\u00e9 claire correspond au noyau contenant de la chromatine et la couronne l’entourant au cytoplasme<\/a>.<\/p>\n
\nIl est vraisemblable que les cellules volumineuses comportent des r\u00e9serves cytoplasmiques alors que les petites cellules en contiennent peu.<\/p>\n
\nL’existence des filaments de chromatine, correspondant \u00e0 des chromosomes condens\u00e9s, sugg\u00e8re que les cellules sont \u00e0 diff\u00e9rents stades de l’\u00e9volution nucl\u00e9aire caract\u00e9ristique des divisions cellulaires. En l’occurrence, les filaments tr\u00e8s \u00e9pais et courts sont rencontr\u00e9s au cours de la prophase de premi\u00e8re division de m\u00e9iose<\/a> au stade pachyt\u00e8ne.<\/p>\n
\nSon organisation g\u00e9n\u00e9rale ainsi que son d\u00e9tail sont d\u00e9crits dans les articles des semaines 10-2019<\/a>, 11-2019<\/a> et 12-2019<\/a> de Codex virtualis.<\/p>\n
\nDOI : 10.4322\/jms.117817<\/a><\/p>\n
\nDOI : 10.1016\/S0040-8166(03)00038-7<\/a><\/p>\n
\n","protected":false},"excerpt":{"rendered":"