2. http://funscubadiver.com/gallery/belize-scuba- photo/belize-painted-tunicate.jpg

3.  Lancelets and Tunicates  Tadpole-like larvae  A notochord, semi-flexible rod running down the length of the animal  A dorsal nerve cord  Pharyngeal slit, an opening between the throat and the outside  Post-anal tail, waste is excreted at the posterior end  Aquatic animals

4. http://en.wikipedia.org/wiki/File:Branchiostoma_lanceolatum.jpg

5. http://en.wikipedia.org/wiki/File:BU_Bio.jpg

6. http://jellieszone.com/images/oikopleura.jpg

7. http://www.meer.org/M20.htm

9.  A characteristic of the invertebrate chordates is bilateral symmetry (symmetry along one axis)  Very long, tubular body structure  Little specialization  Segmentation of the embryo usually occurs early in development  Has a coelomate (fluid-filled body cavity)  Is a deuterostome (first opening of the embryo becomes anus while the opposite side becomes the mouth) http://www.bumblebee.org/invertebrates/images/Amphio xusLanceolatus.jpg http://biodidac.bio.uottawa.ca/ftp/BIODIDAC/ZO O/CHORDATA/DIAGBW/UROC005B.GIF

10.  Are filter feeders of the water; Lancelets use their pharyngeal-gill slits to take in water  Lancelets burrow in soft ground with their mouth facing upward to filter- feed  Urochordates take in water to their body cavity to siphon food (usually plankton)  Plankton gets entangled on the mucus on the endostyle (cavity wall) http://comenius.susqu.edu/bi/202/Animals/DEUTER OSTOMES/cephalochordata/uwinnipeg- Lancelet.jpg

11.  Lancelets (cephalochordata) do not use the gills for respiration but resperate through their skin  Urochordata use an internal gill to extract oxygen from the water they take in http://www.bethel.edu/~johgre/bio114d/LowerVe rts.html

12. Lancelets:  closed circulatory system (has vein and vessels)  pumped by ventral aorta to branched vessels  Lacks a heart  Colorless blood Urochordatas: Open circulatory system Has a ventral heart Contains high levels of metal in blood such as lithium and vandium

13.  Lancelets have a one way stream of wastes that exit the anus  Urochordates take in water through one entrance, extract the food and oxygen before pumping out another entrance http://ian.umces.edu/imagelibr ary/displayimage-4350.html http://www.emc.marico pa.edu/faculty/farabee/ BIOBK/chordate.gif

14. Lancelets:  Has a dorsal nerve running down its body  Slightly larger end at the front which is its brain  Cephalization occurs Urochordatas: Has a nervous system in the larvae stage Digests its own brain in the mature stage Nervous system soon disintegrates

15. Lancelets:  Are feeble swimmers  Use contraction of muscles to move the tail from side to side Urochordata: Are motile during their larvae stage; they have a tail to swim with Once they become mature, they attach to a substrate and become non-motile

16. Lancelets:  Is gonochoristic (there’s a male and female individual)  Releases the appropriate sex cell into the water  Fertilization is external  Develops into a larvae stage Urochorata: Contain both male and female parts (hermaphrodites) Do not fertilize themselves but send sperm out to fertilize other indivduals Keeps the eggs inside themselves

17.  “Chordata.” Bumblebee. 2010. Web. 4/16/2010. http://www.bumblebee.org/invertebrates/CHOR DATA.htm  “Subphylum Urochordata (tunicates)” Meer. Web. 4/16/2010. http://www.meer.org/M20.htm  “Introduction to the Urochordata.” UCMP. 4/16/2010. http://www.ucmp.berkeley.edu/chordata/urochor data.html  “Introduction to the Cephalchordata.” UCMP. 4/16/2010. http://www.ucmp.berkeley.edu/chordata/cephalo. html