Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Hemichordata


Related Topics

  
  Hemichordata - Wikipedia, the free encyclopedia
Hemichordata is a phylum of worm-shaped marine deuterostome animals, generally considered the sister group of our own, the chordates.
Hemichordata are divided into two classes: the Enteropneusta, commonly called acorn worms, and the Pterobranchia, which may include the graptolites.
The exact taxonomic position of hemichordata and whether the group is monophyletic is currently under debate.
en.wikipedia.org /wiki/Hemichordata   (166 words)

  
 Encyclopedia: Hemichordata
Phyla Chaetognatha Echinodermata Hemichordata Chordata Deuterostomes (from the Greek: second the mouth) are one of the two superphyla of animals in the taxonomic branch bilateria, the other being the protostomes.
Pterobranchs have been identified with graptolites, hemichordates of the class Graptolithina (formerly believed to be extinct) since the discovery in 1992 of a living pterobranch identical to fossil graptolites.
Hemichordata consists of Pterobranchia and the Enteropneusta, the acorn worms and sea angels, respectively.
www.nationmaster.com /encyclopedia/Hemichordata   (648 words)

  
 Hemichordates - Phylum Hemichordata
Hemichordata is a small, unusual phylum of worm-like creatures closely related to the phylums Chordata and Echinodermata.
They vary widely in size, from the 8 ft (2.5 m) lengths of the acorn worms to the 1/25 in (1 mm) lengths of the pterobranchs.
Due to these similarities to the phylum Chordata, Hemichordata was once placed in this phylum, but DNA studies have shown that hemichordates are closer to the echinoderms than the chordates, and so they were placed in their own phylum.
www.angelfire.com /mo2/animals1/phylum/hemichord.html   (280 words)

  
 Directory Plug - Science Biology Flora and Fauna Animalia Hemichordata - Free Directory Listings   (Site not responding. Last check: 2007-10-13)
Chordata introduction - Phylum Hemichordata - A brief introduction to the hemichordates from the Biological Sciences at the University of Paisley.
Hemichordata (Acorn Worms and Pterobranchs) - Photograph of an acorn worm (Saccoglossus kowalevskii).
Introduction to the Hemichordata - UCMP Berkeley's introduction to the acorn worms.
www.rovisoft.com /Science/Biology/Flora_and_Fauna/Animalia/Hemichordata   (291 words)

  
 Lab 5 - Deuterostomia   (Site not responding. Last check: 2007-10-13)
Hemichordata – The Hemichordata have some chordate characteristics, but are not considered true chordates.
Classification – The Hemichordata are divided into three classes:  Class Enteropneusta (acorn worms), Class Pterobranchia, and Class Graptolithina.
Fossil Record – The Graptolithina are common as fossils in rocks from the Ordovician (490 - 443 myr bp).
userwww.sfsu.edu /~efc/classes/biol170/lab/Laboratory5.htm   (496 words)

  
 Search Results for Hemichordata - Encyclopædia Britannica
Among the phylum Hemichordata are the enteropneusts (acornworms), which are worm-shaped inhabitants of shallow seas and have a short, conical proboscis, which gives them their common name.
The front end of these animals is shaped like an acorn, hence their common name.
A remarkably diverse assemblage of plants, animals, and microbes live in inland waters, with nearly all major groups of living organisms found in one sort of aquatic ecosystem or another.
www.britannica.com /search?query=Hemichordata   (273 words)

  
 Hemichordata: 3D View of the Web   (Site not responding. Last check: 2007-10-13)
Chordata introduction - Phylum Hemichordata - Chordata introduction - Phylum Hemichordata A brief introduction to the hemichordates from the Biological Sciences at the University of Paisley.
Introduction to the Hemichordata - Introduction to the Hemichordata UCMP Berkeley's introduction to the acorn worms.
Hemichordata (Acorn Worms and Pterobranchs) - Hemichordata (Acorn Worms and Pterobranchs) Photograph of an acorn worm (Saccoglossus kowalevskii).
www.resolve3d.com /Science/Biology/FloraandFauna/Animalia/Hemichordata   (372 words)

  
 [No title]   (Site not responding. Last check: 2007-10-13)
The Phylum Hemichordata is related to the Phylum Chordata compared with which it shows some transitional features.
In the Hemichordata a short elastic rod represents a notochord-like structure occurring in the anterior region [head end].
However, during the lower part of the Paleozoic Era the Hemichordata were very important because they included two very diverse, abundant and biostratigraphically important groups called the graptolites and chitinozoa.
www.geol.lsu.edu /deltaweb/LECTURES/EARTHSCIENCE/chapt7.htm   (5598 words)

  
 Class Graptolithina
In the literature, graptolites are most commonly classed within the "phylum" Hemichordata.
However, there is some doubt that the Hemichordata is a monophyletic group (e.g.
416, who regards the Hemichordata as an artificial grouping of at least two "real" phyla: the Pterobranchia and the Enteropneusta).
www.peripatus.gen.nz /Taxa/Chordata/Graptolithina.html   (780 words)

  
 Chris Cameron's Home Page   (Site not responding. Last check: 2007-10-13)
Cameron, C.B. 2005 Common and Scientific Names of Aquatic Invertebrates from the United States and Canada: Hemichordata.
Cameron, C.B. 2002 The anatomy, life habits and later development of a new species of enteropneust, Harrimania planktophilus (Hemichordata: Harrimaniidae) from Barkley Sound.
Cameron, C.B. 2002 Particle retention and flow in the pharynx of the enteropneust worm Harrimania planktophilus: the filter feeding pharynx may have evolved prior to the chordates.
cluster3.biosci.utexas.edu /faculty/cameronc/CBC.htm   (515 words)

  
 BioG 105/106 | Autotutorial Introductory Biology
Hemichordata (L., hemi = half + chorde = cord)
Two rows of pharyngeal pores run along each side of the trunk.
Examples of each class are shown at right.
instruct1.cit.cornell.edu /Courses/biog105/labs/deuts/hemichordates.html   (266 words)

  
 Lecture 10   (Site not responding. Last check: 2007-10-13)
The Hemichordata, the Early Chordates, and the Fish
The phylum Hemichordata has characteristics intermediate between primitive echinoderms and primitive chordates.
Members of the Hemichordata do have gill slits and a hollow dorsal nerve cord.
nas.cl.uh.edu /novotny/amh09.htm   (1989 words)

  
 Chordata
The Hemichordata ("acorn worms") are mentioned here because they appear to be intermediates between echinoderms and chordates because of their gill-slitted pharynx and dorsal tubular nerve cord.
Gradually, there was less reliance on gills and more on lungs and the circulatory system (heart, blood vessels), which work in connection.
Below are internet links for the Hemichordata, and the two invertebrate subphyla, Urochordata and Cephalochordata.
www.mercy.edu /faculty/knizeski/chordata.html   (610 words)

  
 [No title]   (Site not responding. Last check: 2007-10-13)
Sexes are usually separate; external fertilization is the rule; and the larva closely resembles sea star larva.
Hemichordata is a misnomer since the partial rod inside the animal is not actually homologous to the notochord of Chordata, as was assumed earlier.
However, other characteristics of Hemichordata indicate that it is evolutionarily related to both Echinodermata and Chordata.
www.metu.edu.tr /~bilgincc/ders15.doc   (2263 words)

  
 Hemichordata - ENCYCLOPEDIA - The History Channel UK
Our search facility includes over 50,000 fully cross-referenced historical entries.
Hemichordata, small phylum of marine invertebrates closely related to both the echinoderms (phylum Echinodermata
THE HISTORY CHANNEL and BIOGRAPHY are trademarks of AandE Television Networks used under license ©2004 AandE Television Networks.
www.thehistorychannel.co.uk /site/search/search.php?word=Hemichor   (303 words)

  
 UWRF, Biology 230, General Zoology, Project
In the Phylum Hemichordata the body is divided into...
The lancelets use their pharyngeal gill slits and gill bars for....
The number of species in the phylum Hemichordata is....
www.uwrf.edu /~W1083004/230/zool8_ex3p2.html   (1142 words)

  
 HEMICHORDA, or HEMICHORDATA - Online Information article about HEMICHORDA, or HEMICHORDATA
Search over 40,000 articles from the original, classic Encyclopedia Britannica, 11th Edition.
BAr.ANOII GLOSSUS), but the relationship to the Chordata expressed in the designation Hemichordata cannot be regarded as more than an attractive theory with certain arguments in its favour.
Highlight the code below, right click, and select "copy." Then paste it into your website, email, or other HTML.
encyclopedia.jrank.org /HEG_HIG/HEMICHORDA_or_HEMICHORDATA.html   (495 words)

  
 Biological Diversity 9
The Phylum Hemichordata includes about 90 species of acorn worms.
Some acorn worms living on tidal mud flats have a proboscis, a collar, and a trunk.
Specimen of acorn worm (L), a member of the Phylum Hemichordata, and a fossil of a graptolite (R, Monograptus), a member of an extinct group of hemichorates.
www.estrellamountain.edu /faculty/farabee/biobk/BioBookDiversity_9.html   (6168 words)

  
 Hemichordata: Zoology   (Site not responding. Last check: 2007-10-13)
Classification of the Extant Hemichordata (University of Texas)
Classification of the Rhabdopleuroidea - List of extinct and extant families, genera and species.
Introduction to the Hemichordata (University of California, Berkeley) - Text and Images.
www.infochembio.ethz.ch /links/en/zool_hemicordata.html   (57 words)

  
 GEOL 331 Lecture 34: Graptolites and Basal Chordates
GEOL 331 Lecture 34: Graptolites and Basal Chordates
Echinodermata, Hemichordata, and Chordata: main components of Deuterostomia.
Traditional phylogenies put Hemichordata as sister taxon to Chordata; molecular studies strongly support Echinodermata + Hemichordata to the exclusion of chordates.
www.geol.umd.edu /~tholtz/G331/lectures/331grapt.html   (1171 words)

  
 UWRF, Biology 230, General Zoology, Project
The phylum Hemichordata is not included as a subphylum of the phylum Chordata any longer because they do not posses which of the following characteristics?
Submitted by Brian S. The body of members of the phylum Hemichordata are divided into?
The "notochord" in the phylum hemichordata was proven to be what structure after the 1930's?
www.uwrf.edu /~cg04/230/zool7_ex3p3.html   (1327 words)

  
 Australian Faunal Directory - Checklist for HEMICHORDATA   (Site not responding. Last check: 2007-10-13)
Download checklist for HEMICHORDATA as a RichText file.
Download checklist for HEMICHORDATA as an HTML table, to import into a spreadsheet program such as Microsoft Excel
To expand the checklist, click on the icon to the left of the name you wish to see expanded; if clicking an icon does not expand the checklist there is no element at the next level.
www.deh.gov.au /biodiversity/abrs/online-resources/fauna/afd/HEMICHORDATA/tree.html   (97 words)

  
 Directory Plug - Science Biology Flora and Fauna Animalia Hemichordata Planctosphaeroidea - Free Directory Listings   (Site not responding. Last check: 2007-10-13)
English Science Biology Flora and Fauna Animalia Hemichordata Planctosphaeroidea.
Phylum: Hemichordata Classis: Planctosphaeroidea Ordo: not divided Familia: not divided...
All Science Biology Flora and Fauna Animalia Hemichordata Planctosphaeroidea news
www.rovisoft.com /Science/Biology/Flora_and_Fauna/Animalia/Hemichordata/Planctosphaeroidea   (179 words)

  
 Nearctica - Natural History - Hemichordata and Protochordata
Nearctica - Natural History - Hemichordata and Protochordata
Phylum Hemichordata (Acorn Worms, Pterobranchs, and the extinct Graptolites)
The Echinodermata (Sea Stars, Sea Urchins, Sea Cucumbers, etc. are treated on a separate page and are included here because they are generally considered to be the closest relatives to the Chordates and Hemichordates.
www.nearctica.com /nathist/chordata/primchor.htm   (202 words)

  
 Guide to Animal Names
Enterocoela: Chaetognatha (but inclusion considered doubtful), Chordata, Echinodermata, Hemichordata, Pogonophora
1998, Peterson & Eernisse 2001: Chordata, Echinodermata, Hemichordata
Deuterostomia: Chaetognatha (inclusion considered doubtful), Chordata, Echinodermata, Hemichordata, Pogonophora
tolweb.org /accessory/Guide_to_Animal_Names?acc_id=55   (1231 words)

  
 Encyclopedia article on Hemichordata [EncycloZine]   (Site not responding. Last check: 2007-10-13)
Template:Taxobox begin Template:Taxobox begin placement Template:Taxobox regnum entry Template:Taxobox phylum entry Template:Taxobox end placement Template:Taxobox end Hemichordata is a phylum of deuterostome animals, generally considered the sister group of our own, the chordates.
Products related to Hemichordata: books, DVD, electronics, garden, kitchen, magazines, music, photo, posters, software, tools, toys, VHS, videogames
Visit Curious-Minds.co.UK for educational games and toys, and science kits.
encyclozine.com /Hemichordata   (141 words)

  
 Vertebrate Evolution - Fish
Echinoderms and hemichordata first developed the anus from the blastopore.
While most invertebrates are protostomes and develop the mouth from the blastopore (protostome = "first mouth"), the echinoderms and hemichordata develop the anus from the blastopore, and later the mouth, and thus are called deutrostomes ("second mouth").
We don't know how this happened since there are no intermediate fossils but it certainly was a significant change!
www.bio.miami.edu /tom/bil160/bil160goods/19_verts1.html   (2256 words)

  
 Wiley::Microscopic Anatomy of Invertebrates, Volume 15, Hemichordata, Chaetognatha, and the Invertebrate Chordates
Wiley::Microscopic Anatomy of Invertebrates, Volume 15, Hemichordata, Chaetognatha, and the Invertebrate Chordates
Wiley > Life & Medical Sciences > Comparative Biology > Zoology > Microscopic Anatomy of Invertebrates, Volume 15, Hemichordata, Chaetognatha, and the Invertebrate Chordates
Volume 15 provides specific and exhaustive coverage of hemichordata, chaetognatha, and the invertebrate chordates, examining the basic physiology of such functions as sensation and motor control, respiration, digestion, and reproduction.
www.wiley.com /remtitle.cgi?isbn=0471561223   (219 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.