Phylum
Echinodermata
The following questions will
help you to review the material from the lecture, the laboratory, as
well as the text.
- Give examples of animals
found in the phylum Echinodermata.
- How many species are
found in the phylum?
- Where do you find these
animals? Habitats?
- This phylum is your first
example of a deuterostome taxon. What does that mean? What other
taxa are categorized as deuterostomes?
- Provide a taxonomic
overview of the different classes within the phylum.
- What type of symmetry do
these animals possess? Are there variations in terms of symmetry as
one studies the life cycles of these organisms? What it is the
importance of these observations? Can
one argue that Echinoderms had an
ancestor with bilateral
symmetry? Explain!
- The word "Echinodermata"
means "spiny skinned". Explain.
- What
are ossicles?
- Describe the structure of
the water vascular system as defined by the members within the class
Asteroidea.
- What is the function of
the water vascular system. Is the system unique to the phylum?
- The body anatomy of the
different classes of echinoderms vary widely. Outline the location
of mouth/anus/tube feet for the different classes.
- Outline the external and
internal anatomy of a starfish with the help of a sketch.
- What is pentaradial
symmetry? Do all echinoderms have pentaradial symmetry?
- Draw a cross section of
an arm of a starfish. Outline its anatomy.
- How does a starfish move?
Describe the structure and function of the tube feet found in these
animals.
- Describe the digestive
system of a starfish. How does a starfish feed (use a mussel as an
example [prey])?
- How do these animals
exchange gases with their environment.
- Do echinoderms have a
nervous system? How do they sense the world?
- How does a starfish
reproduce? Describe its life cycle.
- Can a starfish regenerate
lost parts?
- What are pedicellariae?
- Why does the pigmentation
of starfish vary so widely.
- Name some of the local
species of starfish.
- What are brittle stars
[class Ophiuroidea]? How do they differ from members of the class
Asteroidea?
- How do brittle stars
feed?
- In what sense are members
of the class Echinoidea different from the members of class
Asteroidea?
- Where are the "arms" and
tube feet located in a sea urchin?
- What do sea urchins feed
on?
- What is the function of
Aristotle's lantern?
- One normally does not
encounter any sessile organisms on top of an urchin or a starfish.
Why is that?
- How does a sand dollar
differ from a sea urchin?
- Sea cucumbers (class
Holothuroidea) have an unusual anatomy. Describe their basic anatomy
as compared to a starfish.
- What do sea cucumbers
feed on?
- Where can you expect to
find sea cucumbers?
- The phylum Echinodermata
is characterized by a calcareous endoskeleton. Do the sea cucumbers
have such an endoskeleton? Explain.
- Class Crinoidea differs
drastically from the other classes in the phylum. Explain.
- How do sea lilies feed?
- What is a pinnule? Where
are the tube feet located in a crinoid?
- Summarize: What
are the characteristics of the phylum Echinodermata?
- Summarize: What
are the names of the different taxa that you encountered in this
section? Make a table. Memorize the taxa.
