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A previously unknown animal is being studied so that it can be classified.  It is an invertebrate, triploblastic, dorsoventrally flattened, acoelomate, and has flame cells.  Which phylum would you place it in? 

The choanocytes have a flagellum that moves water through the sponge and a collar that extracts food particles from the water. In what group have you encountered very similar cells before?  

Predict what would happen to a sponge that could no longer produce choanocytes:

Suppose you discover a new species of animal that does not have body segments, but is triploblastic, pseudocoelomate, and cephalized. Under the molecular phylogenetic scheme, you would allocate it to which phylum? 

You are asked to study a new species, and are presented with a miniscule amount of DNA from that species.  If you do not find a way to increase the volume of the DNA sample, you will not be able to work with the sample at all.  Which technique should you use to increase the amount of DNA in the sample?

Echinoderms have an endoskeleton, not an exoskeleton.

Stem cells have indeterminate cleavage.

Traditional and molecular phylogenies disagree on which one of the following issues? 

Some members of Platyhelminthes are parasitic.

Millipedes have two total legs per segment whereas centipedes have just one leg per segment.