Chapter 21

Front

What feature characterizes tetrapods but not other vertebrates?

Back

Limbs are the defining feature of tetrapods, distinguishing them from other vertebrates.

Front

Which group of animals is the most successful in terms of species numbers and diversity?

Back

Arthropods are the most successful group of animals, with the highest number of species and diversity.

Front

What is the phylum of animals that have radial symmetry and a gastrovascular cavity?

Back

Cnidaria is the phylum characterized by radial symmetry and a gastrovascular cavity.

Front

What type of skeleton do sharks, skates, and rays have?

Back

Sharks, skates, and rays have skeletons made of cartilage.

Front

What is the phylum of segmented worms that includes earthworms and leeches?

Back

Annelida is the phylum that includes segmented worms like earthworms and leeches.

Front

Define 'amniotic egg' and its significance in tetrapods.

Back

An amniotic egg is an egg that has a protective shell and membranes, allowing for reproduction in a terrestrial environment.

Front

What are the main characteristics of chordates?

Back

Chordates are characterized by having a notochord, dorsal nerve cord, pharyngeal slits, and post-anal tail.

Front

Explain the term 'bilateral symmetry' and its importance in animal evolution.

Back

Bilateral symmetry refers to a body plan that is symmetrical along a single plane, which allows for more efficient movement and organization of body structures.

Front

What distinguishes arthropods from other animal phyla?

Back

Arthropods are distinguished by their exoskeleton, segmented bodies, and jointed appendages.

Front

What is the role of the gastrovascular cavity in Cnidarians?

Back

The gastrovascular cavity serves both digestive and circulatory functions in Cnidarians.