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Definition of oogonium - Merriam-Webster Online Dictionary Learn more about "oogonium" and related topics at Britannica.com Find more about "oogonium" instantly with Live Search See a map of "oogonium" in the Visual Thesaurus www.merriam-webster.com /dictionary/oogonia   (60 words)

Development (biology) - Printer-friendly - MSN Encarta In animals this occurs only during gamete formation, while in some lower plants such as ferns, meiosis may give rise to a haploid stage of the life cycle called a gametophyte, which subsequently produces sexual gametes. The germ cells are formed very early in development and somewhat later they migrate to the developing gonads to become oogonia. At a critical stage, an oogonium divides four times to form a cluster of 16 cells. uk.encarta.msn.com /text_761562707___13/Development_(biology).html   (891 words)

fucoid algae   (Site not responding. Last check: 2007-09-21) Oogonium produce 1-8 eggs and antheridia produce 64 or 128 sperm. The eggs (N) in the oogonium are fertilized by the sperm (N) in the antheridium to make a 2N embryo. Fertilization in natural populations of the dioecious brown alga Fucus ceranoides and the importance of the polyspermy block. biology.fullerton.edu /courses/biol_317/web/Eernisse/Revised_F97/fucoid_algae.html   (1220 words)

Egregia life history Either way, the oogonium is much larger than the vegetative cells of the gametophyte. The oogonium forms a beak through which it will discharge the egg. At the same time, rhizoids begin to grow from the cell closest to the oogonium (on which the sporophyte is growing). www.mbari.org /staff/conn/botany/browns/sarahp/lifehistory.htm   (373 words)

Botany 201 Laboratory, Oomycota The zoospores produced are biflagellated with one flagellum of the whiplash type and the other of the tinsel type. Sexual reproduction is heterogamous and occurs by direct injection of the male nuclei (=sperms) from the antheridium into the eggs contained in the oogonium. A swimming sperm is absent in the Oomycota. www.botany.hawaii.edu /faculty/wong/Bot201/Oomycota/Oomycota.htm   (615 words)

Oogonium definition - Medical Dictionary definitions of popular medical terms Oogonium definition - Medical Dictionary definitions of popular medical terms Oogonium: A female ancestral germ cell that divides several times to give rise to an oocyte that, in turn, develops into an ovum (an egg). The second "o" in oogonium is pronounced separately from the first: o·o·gon·i·um. www.medterms.com /script/main/art.asp?articlekey=4642   (105 words)

template oosphere (egg) enclosed in an oogonium (female) by an antheridium (male). An oogonium with a single oosphere (large circular structure) and an attached antheridium. Note that the wall of the oogonium is still evident. www.cals.ncsu.edu /course/pp318/profiles/oomycetes/oomycetes.htm   (310 words)

Life   (Site not responding. Last check: 2007-09-21) The origin of the male and female gametes comes from small cavities called conceptacles, which are located on the pnuematocysts. The first two nuclear divisions divisions are meiotic and these four haploid nuclei undergo a final mitotic division to produce a total of eight haploid nuclei in each oogonium. In the Genus Cystoseira, only a single functional egg is produced and the remaining seven nuclei are not included in the cytoplasm (Bold and Wynne, 1985). bio.classes.ucsc.edu /bio170/oldsite/spring99/cystoseira/life.htm   (342 words)

Dorlands Medical Dictionary The secondary oocyte (one in the period between the first and second maturation division) is derived from a primary oocyte shortly before ovulation by a division that splits off the first polar body. Oogenesis, depicting only six of the 46 double-stranded chromosomes (oogonium, primary oocyte), three of the 23 double-stranded chromosomes (secondary oocyte, first polar body) and three of the 23 single-stranded chromosomes (ovum, second polar body) occurring in human oogenesis, and showing random assortment of homologous chromosome pairs. Progression through meiosis II is only completed if fertilization occurs, although fertilization and the male chromosomal contribution to the ovum are omitted here. www.mercksource.com /pp/us/cns/cns_hl_dorlands.jspzQzpgzEzzSzppdocszSzuszSzcommonzSzdorlandszSzdorlandzSzdmd_o_03zPzhtm   (3341 words)

SAMPLE QUESTIONS FOR THE THIRD TESTOCTOBER 28 The correct sequence in oogenesis is A. ootid, primary oocyte, secondary oocyte, oogonium, ovum. C. oogonium, primary oocyte, secondary oocyte, ootid, ovum. D. oogonium, ootid, primary oocyte, secondary oocyte, ovum. homepages.culver.edu /faculty/mjones/TEST3.htm   (1244 words)

Political Crossfire Forums :: View topic - Does Prevention of Life Equal Destruction of Life? I think at this point most people can unanimously agree that this oogonium is not a life. Again, if you argue that destroying an egg or an oogonium is killing a life, you're being stupid, and you need to go play with your toes. It is not a potential life, and harming it is not killing a potential life, as one might argue that killing a zygote is. So we take this oogonium, and we homogeneously (on both copies of the chromosome) delete some gene that is essential for a fetus to develop. www.politicalcrossfire.com /forum/viewtopic.php?p=1271314   (4662 words)

Studies in Mycology The antheridial cell touches the oogonium and forms a fertilization tube which penetrates the oogonium. Though not generally accepted, it seems probable that meiosis takes place only in the oogonium and the antheridium and that the entire thallus is diploid (Sansome, 1963, 1966). The oospores can fill the whole oogonium (plerotic oospores) or leave some space between the oogonial and and oospore wall (a plerotic oospores). www.cbs.knaw.nl /simonline/sim_021/content.htm   (5613 words)

oogonium   (Site not responding. Last check: 2007-09-21) Tip: Click on the first link on a line below to go directly to a page where "oogonium" is defined. oogonium : The American Heritage® Dictionary of the English Language [home, ] Oogonium : Online Plain Text English Dictionary [home, ] www.vocamania.com /oogonium.aspx   (262 words)

Amazon.com: "developing oogonium": Key Phrase page   (Site not responding. Last check: 2007-09-21) Many antheridial branches typically are attracted to a single oogonium and may almost completely cover the developing oogonium. The tips of the antheridial branches in contact with the oogonium develop into multinucleate antheridia. This special mass of cytoplasm contains a few chloroplasts and all the nuclei that initially migrated into the developing oogonium but one that becomes the egg nucleus in the young oogonium. www.amazon.com /phrase/developing-oogonium   (487 words)

Fungi These are the slides found in the lab manual pages D10-D12. The content of a young oogonium is more or less homogeneous. As development continues, several thin walled eggs are differentiated within. webnt.calhoun.edu /distance/internet/Natural/bio220-collier/fungi.htm   (45 words)

[No title] Hyphae forming the "body" of the oomycete is diploid sexual reproduction involves the formation of an oogonium (female gametangium) Oogonium is a cell segregated by a cross wall www.d.umn.edu /biology/courses/bio3601/outlinefeb1.htm   (447 words)

Amazon.com: "filling oogonium": Key Phrase page   (Site not responding. Last check: 2007-09-21) See all pages with references to filling oogonium. VV dichotoma 3 Antheridia cylindrical, opening by a slit................4 4 Oospore filling oogonium; oogonia 80-150 m wide....................................................... V fontinalis 4 Oospore not filling oogonium; oogonia 125-250 m wide...................................................... www.amazon.com /phrase/filling-oogonium   (162 words)

Phylum Oomycota   (Site not responding. Last check: 2007-09-21) -the circular female oogonium (female gametangia) and the finger-like male antheridium (male gametangia) attach and fertilize the "oospores" (eggs) in the female oogonium. Notice the long filamentous hyphae with the oogonium (female gametangia) Oospores begin to form within the oogonium and are eventually released the wall breaks down. uregina.ca /~mercerme/2protista02oomycota.htm   (429 words)

Principles of Developmental Biology   (Site not responding. Last check: 2007-09-21) Another important model organism in developmental biology is the African clawed frog, Xenopus laevis. The oocytes are very large, and develop from the primary oogonium [fig. In contrast to Drosophila, each of the 16 cells generated by four rounds of mitoses in the primary oogonium will become a primary oocyte. www.wwnorton.com /college/biology/devbio/chaptersummary/ch4.htm   (1216 words)

LIFE HISTORY The reproductive cell in the antheridium undergoes meiosis once also, but then goes through mitosis four times, ending up with 64 sperm in each packet. When its ready, the oogonium and antheridium spit out the eggs and sperm. Oogonium: cell that produces one or more eggs bio.classes.ucsc.edu /bio170/oldsite/spring99/fucus/lifehistory.html   (515 words)

September 1997 Pituitary gonadotrophins regulate both the rate at which follicles develop and the number which mature per cycle, affected by genetics (species) and environmental factors oogonium proliferate via mitosis before birth (except hamster, rabbit, ferret) (2N) each oogonium eventually produces one viable egg (N) and  2-3 polar bodies, polar bodies contain one set of chromosomes but play no further role campus.devalcol.edu /hammerj/4222/lectures/FEMALE.html   (366 words)

Bean - Pythium   (Site not responding. Last check: 2007-09-21) Scrape lesion with scalpel and place in a drop of water and macerate or crush the material. The oogonium is the large, oval structure and the antheridium is the smaller, somewhat oval, structure touching it. Do not move soil to the lower stems during cultivation. www.plant.uga.edu /Extension/plants/Vegetable/Bean/Bnpyth.html   (63 words)

Pelvetiopsis (pelvetiopsis.htm) 1999), with both genera producing one large egg per oogonium. The former species more closely resembles a dwarf Fucus, whereas the latter is similar in appearance to a small Pelvetia due to its more cylindrical branches (Abott and Hollenberg 1976). When identification is in doubt, specimens can be examined microscopically to determine the number of eggs per oogonium. www.marine.gov /pelvetiopsis.htm   (289 words)

Gametogenesis: process of differentiation that produces cells specialized for reproduction          Once an oogonium become committed to complete oogenesis it begins one of the most remarkable examples of growth of a single cell           Cell may increase from 100 to more than 1,000,000 fold the size of the oogonium          Oogonium becomes committed to proceed through oogenesis when it enters the S-phase of meiosis www.rci.rutgers.edu /~uzwiak/HumanSexuality/HSSpringLect4.html   (704 words)

Coleochaete Images Here, both the female oogonium (note the immature trichogyne) and the male antheridium can be seen. This micrograph shows a mature oogonium complete with an elongate trichogyne. Another important character, the corticated zygote, is shown in this image. www.life.umd.edu /labs/delwiche/lewandowski/coleo.html   (53 words)

CHAP10_images   (Site not responding. Last check: 2007-09-21) The spore has a very thick wall (w) and is contained in the outer wall (ow) of the oogonium (female reproductive cell). The arrows mark the positions of antheridia (male sex organs that fertilise the oogonium). Fig 10.3a Rings of toadstools of mycorrhizal fungi (mainly Hebeloma and Lactarius species) around young birch trees in late autumn in an experimental field plot. helios.bto.ed.ac.uk /bto/FungalBiology/chap10im.htm   (252 words)

The Fungal Web   (Site not responding. Last check: 2007-09-21) (Figures O, P) Grow as aseptate hyphae; asexual reproduction is by formation of motile, biflagellate zoospores in a sporangium; sexual reproduction is by fusion of a "male" sex organ (antheridium) with a "female" sex organ (oogonium), leading to production of thick-walled resting spores (oospores). An oogonium is fertilised by 'male' hyphal branches that clasp onto it and produce antheridia (a). Then the contents of the oogonium are converted to one or more thick-walled resting spores termed oospores (o). www.helios.bto.ed.ac.uk /bto/microbes/fungalwe.htm   (1904 words)

Lab 10 Vocabulary List The female, egg-producing reproductive structure on the gametophytes of non-flowering land plants. The archegonium is comprised of an oogonium surrounded by protective layers of thick-walled, pigmented cells, and may be differentiated into an elongated neck reagion and an expanded basal region, called the venter, which contains the oogonium and egg. The lineage of non-vascular land plants also known as mosses. userwww.sfsu.edu /~biol240/labs/lab_10plantoverview/pages/10vocab.html   (1695 words)

Untitled In sexual oogamous reproduction, there the development of a thickened cell that becomes the oogonium (macrandrous condition); additionally a small side appendage may also develop next to the oogonium that is the male filament (nannandrous condition). Small sproes are released by the male filaments that are attracted to the oogonium. Distinct oogonium and antheridia develop on some branches. www.msu.edu /course/bot/423/algallist3var.html   (519 words)

Oomycota • Female gametangium – oogonium that contains multiple gametes – oospheres in the Saprolegniales • In Saprolegniomycetidae – multiple oospheres in oogonium – formed from a large central vacuole that produces furrows that cleave out oospheres before fertilization • In Peronosporomycetidae – single oosphere in oogonium – oosphere is not delimited by membrane until plasmogamy occurs, no central vacuole, periplasm is present (cytoplasm in oogonium that is not incorporated into oosphere) bama.ua.edu /~ksuberkp/bsc472/lectures/Oomycota.htm   (743 words)

APSnet Featured Photo - Mature oogonium and amphigynous antheridium of Phytophthora cinnamomi   (Site not responding. Last check: 2007-09-21) APSnet Featured Photo - Mature oogonium and amphigynous antheridium of Phytophthora cinnamomi Mature oogonium and amphigynous antheridium of Phytophthora cinnamomi. Images may be used in any software application that supports JPEG file format or viewed in an Internet browser as local files. www.apsnet.org /online/archive/1998/lower35.htm   (197 words)

Meiosis: An Interactive Animation This animation is also available for offline use in single user and multi-user versions and on the CELLS alive! Diploid Cell (2N): From a preceding mitotic division, the Oogonium (Spermatogonium) enters meiosis with DIPLOID (2N) chromosomes but TETRAPLOID (4N) DNA. Chromosomes then duplicate to produce SISTER CHROMATIDS (or HOMOLOGOUS DYADS). www.cellsalive.com /meiosis.htm   (244 words)

Sitemap for http://moldnhouse.com Following are some steps roofing contractors, consultants and specifiers should take In fungi and fungus-like organisms, spores are often classified by the structure in which meiosis and spore production takes place, such as a telium, ascus, basidium, or oogonium, which produce teliospore, ascospores, basidiospores, and oospores. For significant mold growth to occur, there must be a source of water and a substrate capable of sustaining the growth. moldnhouse.com /sitemap_1.html   (436 words)

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