1 / 8

Phylum chordata

Phylum chordata. Invertebrate chordates (no backbones) vertebrate chordates (have backbones). All chordates have the following:. Notochord: Flexible dorsal supporting rod Usually replaced by a backbone as embryo develops Hollow dorsal nerve cord

harmon
Download Presentation

Phylum chordata

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. Phylum chordata Invertebrate chordates (no backbones) vertebrate chordates (have backbones)

  2. All chordates have the following: • Notochord: • Flexible dorsal supporting rod • Usually replaced by a backbone as embryo develops • Hollow dorsal nerve cord • As opposed to the ventral nerve in other animals • Pharyngeal (throat) slits • In aquatic chordates, these gills are slits • In terrestrial chordates, these slits disappear early in embryonic development

  3. Invertebrate chordates • Tunicates and lancelets • Not many of these but they are of great evolutionary interest • Possible link between vertebrates and all other animals

  4. Vertebrate chordates • Fish (3 classes) • Amphibians • Reptiles • Birds • Mammals

  5. Vertebrates (subphylum vertebrata) • Characteristics: • Endoskeleton • Vertebral column (“backbone”) • Closed circulatory system • Ventral heart • Usually four appendages

  6. Temperature control • All vertebrates must keep their body temperatures within a certain range. There are 2 ways of doing this • Ectotherms: change behavior in response to temperature fluctuations • Lack effective insulation, have low metabolic rates, are fish, amphibians, reptiles • Endotherms: rely on heat generated by their bodies (and some behavioral strategies) • They have insulation, high metabolic rates, birds, mammals and possible dinosaurs

  7. Fish • Aquatic vertebrates with scales, fins and pharyngeal gills • Classes: • Agnatha: primitive jawless fish that are parasitic or scavegers, includes lampreys and hagfish • Chondricthyes: ancient group of mostly predatory cartilaginous fish (skeleton entirely cartilage), includes sharks, skates and rays • Osteichthyes: “regular” fish with a bony skeleton. 97% of all fish are in this class

More Related