Exam 19: Animalia

In all eutherians and some marsupials,offspring develop internally in association with the ________.

Although some exceptions exist,the majority of mollusks are protected within a shell that is secreted by the animal's ________.

The conservation organization Ocean Blue has developed a seafood recommendation list that advises avoiding many captive-reared species; why might seafood captured from sustainable wild stocks be more desirable?

Neighboring plant or fungal cells share a common cell wall,making multicellularity relatively simple; how do animal cells remain connected to one another?

The longer incubation period observed with the egg of reptiles and birds,resulting in a more functional individual after hatching,is possible because of the addition of a ________ to the egg.

Adult sea stars are considered to be radially symmetrical because

Most insects reproduce as rapidly as possible; however,7 of the approximately 170 species of North American cicadas reproduce in 13- or 17-year cycles; they are known as the ________ cicadas.

Cephalopods are demonstrably the most intelligent invertebrate animals; most biologists suspect that their ________ best account(s)for their intellectual development.

Conservation biologists estimate that 20 percent of the world's bird species that existed 2,000 years ago are now extinct.

Fossil evidence suggests that feathers existed prior to the development of a flight-capable skeleton; because these feathered animals could not fly,biologists suspect that the initial adaptive value for feathers was related their ability to

In addition to embryonic similarities,the chordates and echinoderms also each possess a hollow nerve cord located on the ________ side of the body.

With the exception of the sponges,all animals develop embryologically in one of two ways; the chordates and echinoderms,as deuterostomes,

Cephalization describes a body plan that is characterized by

What occurs during ecdysis?

Although adult echinoderms display radial symmetry,they are not considered closely related to the cnidarians and ctenophores.

Which arthropod is properly matched with the correct class?

Reptiles display many adaptations supporting a terrestrial lifestyle; the most significant in reducing their dependency on an aquatic habitat is ________.

Following gastrulation,most animal embryos develop three embryonic tissue layers; the endoderm forms the ________ layer.

Cephalization is clearly adaptive for the free-living planarians that must locate their food; why would the parasitic flukes and tapeworms retain cephalization?

Some mollusks feed on cnidarians,absorb intact cnidocytes,and migrate these cnidocytes into their body surface.What possible benefit could the mollusk derive from this behavior?