Download Chordate Test Review Pre AP

Chordate Test Review Key
All Chordates share four major characteristics. At some time during their development,
they will have a _______notochord___________, which becomes the spine in
vertebrate animals. They will also have ______pharyngeal pouches_______, which
become the gill slits of aquatic chordates.
They have a __dorsal hollow nerve cord___ which becomes the spinal cord and brain,
and they will have a postanal tail.
There are only two types of ____invertebrate chordates_______. These are the tunicates
and lancelets. All other chordates have a backbone, and belong to the
subphylum ____Vertebrata_________.
Fishes make up 4 classes of vertebrate. Two of the classes, Myxini and
Cephalaspidomorphi, are jawless fishes. They belong to the superclass ___Agnatha____.
The only members of this superclass of jawless fishes are the hagfish and
_____lamprey_____.
Sharks, skates and rays are in the class _____Chondrichthyes_________.
These fishes have a skeleton composed of _____cartilage__________ rather than bone.
There are more bony fishes, from the class _________Osteichtyes_________, than any
other type of fish.
All fishes are characterized by a ____2____ chambered heart, a closed circulatory
system and respiration through gills.
Gills function by allowing ___oxygen_______ to diffuse from the water into the
capillaries of the gill filaments, and _______carbon dioxide____ diffuses from the blood,
into the water.
Fishes also have a ________lateral line system___________ that allows them to detect
movement in the water.
The other 4 classes; _____amphibians______, ______reptiles________,
______birds (Aves) ___________, and _________mammals___________ can be
recognized as being either endothermic or ectothermic.
The _________amphibians _____________ and _________reptiles____________ are
ectotherms. The _______birds_________ and ______mammals_______ are endotherms.
Endothermic animals produce their own body heat. Their temperature remains fairly
constant, regardless of their surroundings. Because of this, they must have a way to
insulate their bodies to conserve heat.
All _____birds (Aves) _____, have a covering of feathers, and in
_____mammals____ this covering will be in the form of hair or fur.
All endothermic animals have a __4______chambered heart.
In addition to the feathers of birds, they are also characterized by having 2 legs and 2
____wings_____. And they have a ___beak______ with no teeth.
Mammals can be subdivided by the way they bear their young. ___Placental_______
mammals are the most common. Their young develop inside a membrane sac known as a
_________placenta_________. __________Marsupial__________ mammals, such
as kangaroos, complete their development inside a pouch. There are only two egg laying
mammals, known as ______monotremes________. They are the _____platypus______
and the ___echidna (spiny anteater) ______.
The class Mammalia gets its name from the ___mammary_____ glands of the
females, which serve to supply _____milk______ for the young.
Mammals can be found on the land, in the water ( _____whales__________ and
_____dolphins_____) and some are even capable of flight (____bats______).
Ectotherms include the classes _____Amphibia__________ and
______Reptilia________. Ectothermic animals do not produce or store a lot of heat.
Their body temperatures will change to match their surroundings.
Ectothermic animals have ___3____ heart chambers.
In most ____reptiles_______, the heart is partly divided. The exceptions to this are the
_____ crocodilians______, who have a heart with four chambers.
Members of the class _______Amphibia____________ start off in a larval form in the
water. They have characteristics of fish, such as gills and fins. They will eventually
undergo a change, called a ________metamorphosis_____________ in which they loose
their gills and gain a set of ____lungs_____ for respiration. Most will also gain legs.
Even though they have legs to move about on the land, most have to remain fairly close
to water. They have a very sensitive skin that must be kept moist. In fact, most of them
carry out _________respiration_____ through their skin and can suffocate if it dries out.
Members of the class _____Reptilia_________ do not have this problem, because they
have a scaly skin that helps them retain moisture.
_______Reptiles____________ do not undergo metamorphosis either. They develop
in an ____amniotic_________ egg with a ______leathery____________ shell. Once they
hatch, respiration is only through _____lungs________.
Most reptiles have the ability to pick up scent molecules with their tongue. They flick
their tongue, and then insert it into the _____Jacobson’s ______ organ, which is located
on the roof of the mouth.
The hearts of mammals and birds are much more efficient than those of reptiles and
amphibians.
The reason for this is ________the oxygenated blood is separated from the deoxygenated
which allows the cells to make more energy to keep the body warm_________________
Some mammals, known as ____bats_____ are unique because they are capable of flight.
Humans are classified as mammals because we are _____endothermic_____, meaning we
maintain a constant body temperature, we have a ______4_____ chambered heart,
our bodies have a sparse covering of _____hair______, and females have
_______mammary glands_________ which produce milk for our young.