Phylum
Chordata:
Introduction/Fishes
The following questions will
help you to review the material from the lecture, the laboratory, as
well
as the text.
-
Briefly describe the
diversity
of animals one can expect to find within the phylum Chordata. Give
examples.
-
Members of the phylum
Chordata
have four major characteristics in common. Describe these four
features
and explain how they can be used to unify the taxon.
-
Would an adult elephant have
the
four above characteristics? Explain.
-
Which three subphyla belong
to
the phylum Chordata? How do these subphyla differ from each other?
-
What are tunicates? Where can
you expect to find them?
-
Briefly describe the anatomy
of
an adult tunicate with the help of a drawing. Describe the function
of
each structure that you mention in your diagram.
-
How do tunicates feed?
Reproduce
(describe the basic life cycle of a tunicate)?
-
Compare and contrast the
structure
of an adult tunicate and the larval form. How do they differ from
each
other? How are they similar?
-
How do lancelets differ from
tunicates?
How are they similar? Speculate on the origin of lancelets based on
your
knowledge of the tunicates.
-
Briefly describe the anatomy
of
a lancelet. Point out the features that makes it a chordate.
-
Describe the diversity of the
subphylum Vertebrata. What do the vertebrates have in common?
-
Is it appropriate to divide
the
field of zoology into invertebrate and vertebrate zoology
(i.e. invertebrates
vs. vertebrates)?
-
Most of the vertebrates are
fishes.
What kind of fishes dominate in the earth's aquatic realm? Show how
the
different lineages of fishes are connected to each other.
-
Briefly describe the major
lineages
of fishes as covered in our class.
-
What kind of fishes are found
in the superclass Agnatha? How do they differ from bony fishes?
-
How do lampreys and hagfishes
differ from each other? What do they feed on?
-
What are the lampreys
considered
to be problematic? What kind of impact do lampreys have on humans?
-
Describe the life cycle of a
lamprey?
-
Which classes of fish are
found
in the superclass Gnathostomata? How do these fishes differ from the
superclass
Agnatha?
-
The extinct class
Placodermata
was covered in our class. Why do you think so? Do the placoderms
have any
interesting characteristics one should pay attention to? Explain.
-
How did jaws evolve? Explain
the
current thinking about the origin of jaws in vertebrates. How did
the evolution
of jaws affect the success of the vertebrates?
-
What is the name of the
largest
(in size) fish species?
-
Characterize the sharks and
the
rays (class Chondrichthyes).
-
Sharks are typically
perceived
as a threat to humans. This perception has escalated over the last
twenty
years. Discuss the circumstances that have lead to this state of
affairs.
-
What is the main
characteristic
of this taxon?
-
Why was this group so
successful?
-
Describe the external anatomy
of a shark (focus on the location and the names of the different
fins).
-
How are the types of fins
related
to how a shark moves?
-
How does a shark differ in
movement
compared to a typical bony fish (Osteichthyes)?
-
How do sharks maintain "lift"
as they move through the water?
-
How have some sharks solved
the
buoyancy problem?
-
What are placoid scales?
Describe
them? What is their function?
-
Describe how sharks do gas
exchange?
How does it differ (if at all) from a bony fish?
-
How do sharks detect prey?
Imagine
an injured fish a mile away from a Great White Shark. Describe the
different
sensory systems a shark uses to home in on its prey as well as the
sequence
in which they come into play as the shark is approaching the injured
fish.
-
Describe the structure and
function
of the lateral line system.
-
What is the function of the
ampullae
of Lorenzini?
-
Many sharks have a
nictitating
membrane associated with their eyes. What is its function?
-
What is unusual about the
shark's
teeth (e.g. a Great White) in terms of their structure and
morphology?
-
What is so special about Charcaradon
megalodon?
-
Describe the diversity of
lifestyles
found in sharks (ways of living, size, habitats).
-
What is unusual about the
whale
shark and the basking shark?
-
Can you give some other
examples
of unusual sharks (they do not all fall into the "typical" Great
White
category).
-
Many shark species are
threatened
by the growing human population. Explain how humans take advantage
of these
animals.
-
How do rays and skates differ
from sharks in terms of anatomy, life style and feeding habits?
-
How do skates and rays differ
from each other?
-
What do rays and skates
typically
feed upon? How can you tell?
-
What is a ratfish (chimerae)?
