Biology Test 3
Chapter 23 Animals 1: Major Invertebrate Groups
23.1 old genes new drugs
* Vertebrates – an animal that has a back bone
* Mammals, birds, reptiles, amphibians, and fish
* Invertebrates – an animal that does not have a back bone
* More than 97%
* Cone snails (genus Conus) found in warn nearshore waters of South Pacific, patterned shells, they are predators and produce venom.
* Produce a pain killing drug call ziconotide (prialt), unlike morphine it is non addictive.
23.2 animal traits and trends
* Animals – multicelled heterotrophy with unwalled cells. Most ingest food and are ...view middle of the document...
They attach to an underwater surface or drift along. Their food can arrive from any direction.
* Bilateral symmetry – having paired structures so the right and left halves are mirror images
* Bilateral animals typically have cephalization.
* Move through the world head first and use their sensory structures on the head to seek out food and detect threats
* Head ends have an opening for taking in food.
* Cephalization – having a concentration of nerve and sensory cells at the head end.
* Protostomes – lineage of bilateral animals in which the first opening on the embryo surface develops into a mouth
* Deuterostomes – lineage of bilateral animals in which the second opening on the embryo surface develops into a mouth.
* Pseudiciekin – unlined body cavity
* Tape worm
* Coelom – body cavity lined with tissue derived from mesoderm.
* Segmentation – a division of a body into similar units repeated one after the other along main axis.
23.3 animal origins and early radiations
* The colonial theory of animal’s origins says that the first animals evolved from a colonial protest.
* Choanoflagellate – member of the protest group most closely related to animals
* Placozoan – the simplest modern animal with an asymmetrical flat body, four types of cells, and a small genome.