Exam 32: An Overview of Animal Diversity

Fossil evidence indicates that the following events occurred in what sequence,from earliest to most recent? 1)Protostomes invade terrestrial environments. 2)Cambrian explosion occurs. 3)Deuterostomes invade terrestrial environments. 4)Vertebrates become top predators in the seas.

-Which of the following is a point of conflict between the phylogenetic analyses presented in these two figures?

Arthropods invaded land about 100 million years before vertebrates did so.This most clearly implies that

Among the characteristics unique to animals is

Use the following information to answer the questions below. The most recently discovered phylum in the animal kingdom (1995)is the phylum Cycliophora.It includes three species of tiny organisms that live in large numbers on the outsides of the mouthparts and appendages of lobsters.The feeding stage permanently attaches to the lobster via an adhesive disk,and collects scraps of food from its host's feeding by capturing the scraps in a current created by a ring of cilia.The body is sac-like and has a U-shaped intestine that brings the anus close to the mouth.Cycliophorans are eucoelomate,do not moult (though their host does),and their embryos undergo spiral cleavage. -Basing your inferences on information in the previous paragraph,to which clade(s)should cycliophorans belong? 1)Eumetazoa 2)Deuterostomia 3)Bilateria 4)Ecdysozoa 5)Lophotrochozoa

The last common ancestor of all animals was probably a

What was an early selective advantage of a coelom in animals? A coelom ________.

Which developmental mode is correctly matched with the specific characteristics?

What does recent evidence from molecular systematics reveal about the relationship between grades and clades?

The figure above shows a chart of the animal kingdom set up as a modified phylogenetic tree.Use the diagram to answer the following questions. -Which group contains diploblastic organisms?

Use the following two diagrams (A and B)to answer the questions below. A: Morphological phylogeny. B: Molecular phylogeny. -In the traditional phylogeny (A),the phylum Platyhelminthes is depicted as a sister taxon to the rest of the protostome phyla,and as having diverged earlier from the lineage that led to the rest of the protostomes.In the molecular phylogeny (B),Platyhelminthes is depicted as a lophotrochozoan phylum.What probably led to this change?

In individual insects of some species,whole chromosomes that carry larval genes are eliminated from the genomes of somatic cells at the time of metamorphosis.A consequence of this occurrence is that

The larvae of some insects are merely small versions of the adult,whereas the larvae of other insects look completely different from adults,eat different foods,and may live in different habitats.Which of the following most directly favours the evolution of the latter,more radical,kind of metamorphosis?

While looking at some seawater through your microscope,you spot the egg of an unknown animal.Which of the following tests could you use to determine whether the developing organism is a protostome or a deuterostome? See whether the embryo ________.

Use the following information to answer the questions below. Trichoplax adhaerens (Tp)is the only living species in the phylum Placozoa.Individuals are about 1 mm wide and only 27 μm high,are irregularly shaped,and consist of a total of about 2000 cells,which are diploid (2n = 12).There are four types of cells,none of which are nerve or muscle cells,and none of which have cell walls.They move using cilia,and any "edge" can lead.Tp feeds on marine microbes,mostly unicellular green algae,by crawling atop the algae and trapping it between its ventral surface and the substrate.Enzymes are then secreted onto the algae,and the resulting nutrients are absorbed.Tp sperm cells have never been observed,nor have embryos past the 64-cell (blastula)stage. -If Tp sperm are observed by future researchers,how many chromosomes should be found in a Tp sperm nucleus?

The following questions refer to the description below. You have taken an introductory course in animal biology and know that animals have evolved with different types of symmetry.Animals that show radial symmetry have a top and bottom,but do not have a left or right side,nor a front or back end.Animals that show bilateral symmetry have a top and bottom,left and right sides,and distinct anterior and posterior ends. -You and a friend have flown to the coast of British Columbia to do some hiking and whale watching.As you are walking along the beach collecting shells,you notice a strange animal washed up on the beach and it is not a species that you recognize.Just by looking at the animal,what is a quick way that you can surmise the animal's mode of locomotion and method of food acquisition?

Use the following information to answer the questions below. Trichoplax adhaerens (Tp)is the only living species in the phylum Placozoa.Individuals are about 1 mm wide and only 27 μm high,are irregularly shaped,and consist of a total of about 2000 cells,which are diploid (2n = 12).There are four types of cells,none of which are nerve or muscle cells,and none of which have cell walls.They move using cilia,and any "edge" can lead.Tp feeds on marine microbes,mostly unicellular green algae,by crawling atop the algae and trapping it between its ventral surface and the substrate.Enzymes are then secreted onto the algae,and the resulting nutrients are absorbed.Tp sperm cells have never been observed,nor have embryos past the 64-cell (blastula)stage. -In how many of the following ways is Tp unlike the typical animal? 1)Tp is multicellular. 2)Tp lacks muscle and nerve cells. 3)Tp has cilia. 4)Tp has a different place where digestion of food occurs. 5)Tp lacks cell walls.

Which of the following traits differentiates animals from plants and fungi?

With the current molecular-based phylogeny in mind,rank the following from most inclusive to least inclusive. 1)ecdysozoan 2)protostome 3)eumetazoan 4)triploblastic

Which of the following characteristics generally applies to protostome development?