______ are endothermic vertebrates that have skin covered with fur or hair and a four chambered heart.
______ are invertebrates that have stinging cells and take in food into a central body cavity.
Ribs protect the heart and ______.
An _____ is an animal that controls the internal heat it produces and regulate its own temperature.
A/An ______ is a vertebrate this is ectotherm and spends its early life in water and its adult life on land.
A/An _____ is a group of similar cells that perform a specific function.
All mollusks have a thin layer of tissue called a _____ that covers their internal organs and have an organ called a foot.
All ____ have three characteristics: a notochord, a nerve chord and pouches in the throat area.
Structures and behaviors that allow animals to perform their functions are called _____.
A/An ______ is an ectothermic vertebrate that has a scaly skin and lungs and lays eggs on land.
____ are animals without a backbone.
Jellyfishes and _____ are examples of cnidarians.
_____ are asymmetrical invertebrates that do not have tissues or organs.
All chordates have a ______ cord that runs down the back and connects the brain to nerves in other parts of the body.
An animal has _____ symmetry if many imaginary lines can be drawn through its center to divide it into mirror images.
A ____ is a flexible rod that supports a chordate's back.
An animal that produces little internal body heat is called an _____.
_____ worms are the simplest animals with a brain.
Jawless fishes have skeletons made of ____, a tissue more flexible than bone.
An endoskeleton provides _____ with places to attach