Exam 19: Animalia

Of the labeled features in the following diagram,only the dorsally positioned nerve cord would be present in an echinoderm.

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

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.

Gastropods make extensive use of the radula;which letter on the following diagram indicates its location?

The periodic cicadas have evolved reproductive cycle lengths with prime number patterns;since prime numbers have no common multiples,it's very unlikely that high predator densities will correspond with a hatching event.

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?

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

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?

Ectothermy describes a strategy to homeostatically regulate a body temperature to be below the ambient temperature,thus leading to the phrase cold-blooded.

The specifics of metamorphosis vary among the arthropods;when the life cycle is characterized by ________,complete metamorphosis has occurred.

Only about 5 percent of extant mammals are classified either as marsupials or monotremes;the remaining 95 percent are classified as ________.

Most gardeners are pleased to discover earthworms in their gardens because earthworms improve the soil when they

During cephalization,the structures that develop at the anterior margin of a bilateral animal are primarily associated with ________ and ________.

For the insects that undergo complete metamorphosis,the larva matures to form a ________.

Chitin occurs in several kingdoms and numerous animal phyla,but its greatest adaptive expression is seen in the:

Cnidarians have a gastrovascular cavity rather than a complete gut;in what way(s)would this arrangement be less functional in comparison to a complete digestive system like that in the rotifer?

The myriapods are a relatively small group of arthropods;its most common members are the ________ and ________.

The success of the amniotic egg was the development of a completely water- and airtight shell that prevented moisture loss.

Many of the organ systems observed in vertebrates are present in the annelids,the simplest coelomates;an exception is the ________,which helps explain why earthworms leave the soil on rainy days.

The head,thorax,and abdomen of the insect body plan developed as individual segments fused;because each segment originated one pair of appendages,a reasonable hypothesis is that the thorax developed when ________ segments fused.