1 / 33

Chordates

Chordates. By Eduardo Alexander Becerra and Caleb Jennings Staurseth. What Defines a Chordate?. Its.. Notochord Dorsal Nerve Chord Pharyngeal Slits Post-Anal Tail. Chordate Embryos and Tissues. Chordates have 3 layers of tissue Deutersomes Anus forms first, then the mouth forms

patience-leblanc
Télécharger la présentation

Chordates

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chordates By Eduardo Alexander Becerra and Caleb Jennings Staurseth

  2. What Defines a Chordate? • Its.. • Notochord • Dorsal Nerve Chord • Pharyngeal Slits • Post-Anal Tail

  3. Chordate Embryos and Tissues • Chordates have 3 layers of tissue • Deutersomes • Anus forms first, then the mouth forms • Coelomates • Bilaterial symmetry • Endoskeleton • Complete digestive system

  4. Notochord: A flexible rod-like structure that is similar to a spine

  5. Dorsal Nerve Chord: The nervous system in chordates.

  6. Pharyngeal Slits: Gill like structures that are located on the pharynx

  7. Post-Anal Tail: A tail that extends beyond the anus.

  8. The 3 Branches • The three subdivisions or ‘clades’ of chordates: • Craniates • Lancelets • Tunicates

  9. Tunicates(subphylum Urochordata) • The deepest branching lineage of chordates. • Resembles other chordates most intensely during larval stages • Larva tunicate settles down, and goes through metamorphasis • Many chordate characteristics disappear • Tail and notochord go away, nervous system is destroyed • Often called “sea squirts” as they shoot out water from their anus to jet away when attacked

  10. Tunicate Tunicate lifecycle

  11. Polycarpa Auruta

  12. Lancelet(subphylum cephalochordata) • Named after their bladelike shape • Lancelet Larvae: • Devolop a notochord, dorsal, hollow nervecord, pharyngeal slits, and post-anal tail • Food source is plankton • Post metamorphasis: • Spend most of their time in the sand, leaving their mouth exposed, catching their food. • Segmented muscle developed from somites - found in all chordate embryos

  13. Adult Lancelet

  14. Craniates • craniates (literally means cranium/skull)are unique from their other chordate relatives in a number of characteristics: • Possess 2 clusters of ‘Hox’ genes • Neural Crest - collection of cells at the dorsal margins in an embryo which give rise to a variety of structures: • Teeth • Many bones and cartilage of the skull • Inner layer of skin (dermis) on the facial region • Sensory capsules in which sense organs such as eyes develop.

  15. Craniates are seperated into 2 major Clades • Myxini/Hyperotreti (hagfish) • Vertebrata

  16. Myxini -Pacific Hagfish- • These bad boys have a • skull made of cartilage, and • swim in a snake-like motion • They Also have a small brain, eyes, ears, and a nasal opening which connects to their pharynx

  17. Vertebrata Craniates Lampreys (Cephalaspidomorphi) are the oldest living lineage of vertebrates, and lack a jaw

  18. Vertebrata Craniates • Conodonts (“cone teeth”) • Early, slender, soft-bodied verebrates with advanced eyes, and lacked a jaw

  19. Vertebrata Craniates Ostracoderms Additional vertebrates stemmed from the same period. Ostracoderms -- had paired fins, inner ear and sense of balance, a muscular pharynx, and armored bodies

  20. Vertebrata Craniates • Gnathostomes (“jaw mouth”) = jawed vertebrates • The jaw enabled animals to grip food and chew it • up for digestion • 4 Hox Genes • Enhanced sense of smell and vision resulted in a larger forebrain • Have lateral line systems, which detected vibrations • Consisted of placoderms = “plate-skinned” and acanthodians, which are closely related to ray-finned fish and lobe-finned fish • Went extinct around 360 million years ago

  21. Vertebrata Craniates • Chondrichthyans • Consists of Sharks, rays, and their close relatives • Have skeleton made mostly of cartilage and loads of calcium, developed mostly in embryonic stages • Sharks: • have a spiral valve, which makes up for the sharks short digestive tract • Have noses meant only for smelling, not breathing • Eggs fertelized internally • Some species are oviparous • Some species are ovoviviparous • Rays: • Bottom-dwellers, whiplike tails, venomous barbs

  22. JAWS - Great White Large Stingray

  23. Vertebrata Craniates • Osteichthyes(“Bony Fish”) • Bony endoskeletaon • Breathe through gills • protected by bony flaps called operculum • Buoyancy controlled with an air sac called a swim bladder Common fish

  24. Vertebrata Craniates • Osteichthyes continued… • Ray-Finned Fishes • Majority of aquatic osteichthyans • Bass, trout, perch, tuna, herring • Fins allow for increased • maneuverability • defense Blue-Fin Tuna

  25. Vertebrata Craniates • Osteichthyes continued… • Lobe-Fins • Fins have a thick muscle layer in pectoral and pelvic fins • Used to “walk” across the sea floor • Only three lineages left today • Coelacanths, lungfishes, and tetrapods Coelacanths lungfish

  26. Vertebrata Craniates • Tetrrapods -- gnathostomes with feet • Have 4 feet with digits • Able to support weight on land • No gill slits • in embryonic development, what would have developed into gill slits creates ears and glands • Overall, adaptions making organisms fit for land

  27. Vertebrata Craniates • First Group of Tetrapods: Amphibians • 4,800 species today: • Comprising of salamanders, frogs and caecilians • Live on land and in water • Scientists believe that the earliest tetrapods were heavily tied to water

  28. Tadpole Life Cycle

  29. Sources • http://depts.washington.edu/fhlk12/links/StudentProjects/Images/CionaTunicateBiology/tadpole_low.gif • http://lh3.ggpht.com/_yItZwKwfM-I/TTPNPSBC1LI/AAAAAAAAA_U/HobmwJ3weYo/chordatecharaceristics219.jpg • http://www.blc.arizona.edu/courses/schaffer/182/Vertebrates/AmphioxusPurvis.jpeg • http://www.blc.arizona.edu/courses/schaffer/182/Vertebrates/AmphioxusPurvis.jpeg • http://www.google.com/imgres?um=1&hl=en&biw=1290&bih=658&tbm=isch&tbnid=vC0HTQ2FBF6zuM:&imgrefurl=http://northgoessouth.com/tag/giant-bluefin-tuna/&docid=meFYCiQ-KwXP0M&imgurl=http://northgoessouth.com/wp-content/uploads/2010/07/27Tuna-t_CA0-articleLarge.jpg&w=600&h=315&ei=axmOT8KNEsGo2wXvvr2DDA&zoom=1&iact=hc&vpx=170&vpy=384&dur=1148&hovh=163&hovw=310&tx=199&ty=95&sig=110107029035550495494&page=2&tbnh=110&tbnw=209&start=18&ndsp=20&ved=1t:429,r:15,s:18,i:224 • http://www.google.com/imgres?um=1&hl=en&biw=1290&bih=658&tbm=isch&tbnid=mEB3K2EHov4tkM:&imgrefurl=http://www.richardherrmann.com/PersonalProjects/GameFish.html&docid=QxMmdZhCQxO_NM&imgurl=http://www.richardherrmann.com/PersonalProjects/images-persProjects/05BluefinTuna011637.jpg&w=700&h=518&ei=axmOT8KNEsGo2wXvvr2DDA&zoom=1&iact=hc&vpx=777&vpy=210&dur=1074&hovh=193&hovw=261&tx=118&ty=118&sig=110107029035550495494&page=3&tbnh=151&tbnw=199&start=38&ndsp=23&ved=1t:429,r:14,s:38,i:266 • http://images.nationalgeographic.com/wpf/media-live/photos/000/005/cache/giant-stingray-bluesheet_547_600x450.jpg

  30. Sources part 2 • http://www.biog1105-1106.org/labs/deuts/chordates.html • jaws.jpg (640×480) • http://www.google.com/imgres?um=1&hl=en&biw=1290&bih=658&tbm=isch&tbnid=1QBTNyeBRDnkjM:&imgrefurl=http://palaeos.com/vertebrates/gnathostomata/gnathostomata.html&docid=ZJEYZYbF12ssWM&imgurl=http://palaeos.com/vertebrates/gnathostomata/images/Gnathostomata1.jpg&w=400&h=262&ei=aw2OT6X5BIXs2QWvgvSgDA&zoom=1&iact=rc&dur=598&sig=110107029035550495494&page=2&tbnh=107&tbnw=163&start=19&ndsp=22&ved=1t:429,r:8,s:19,i:145&tx=122&ty=70 • http://www.google.com/imgres?start=89&um=1&hl=en&biw=1290&bih=658&tbm=isch&tbnid=C4sKRRafgcCXkM:&imgrefurl=http://palaeos.com/vertebrates/bones/gill_arches/epibranchial.html&docid=WvfSn5InEtkJlM&imgurl=http://palaeos.com/vertebrates/bones/gill_arches/images/TristychiusRecon.gif&w=500&h=143&ei=QQ2OT7SgBqjW2AXIoemiDA&zoom=1&iact=rc&dur=211&sig=110107029035550495494&page=5&tbnh=56&tbnw=195&ndsp=24&ved=1t:429,r:12,s:89,i:31&tx=155&ty=32 • https://www.google.com/search?q=neil+patrick+harris&um=1&ie=UTF-8&hl=en&tbm=isch&source=og&sa=N&tab=wi&ei=RAKOT4iSDMKcgQfe3Y3yDQ&biw=1290&bih=658&sei=RwKOT560DMjq2QXe_KWfDA • http://30.media.tumblr.com/tumblr_lb0tidWR5R1qd8z9zo1_250.gif • http://upload.wikimedia.org/wikipedia/commons/c/cd/Tunicate_komodo.jpg • http://tolweb.org/Craniata • http://cdn.physorg.com/newman/gfx/news/hagfish.jpg • http://farm4.static.flickr.com/3357/3476498612_d29a5984ed.jpg

More Related