Chapter 32 Test (1-10)

Question 1

Which of the following was probably the least important factor in bringing about the Cambrian explosion?

A) the accumulation of diverse adaptations, such as shells and different modes of locomotion

B) the accumulation of sufficient atmospheric oxygen to support the more active metabolism of mobile animals

C) the emergence of predator-prey relationships among animals

D) the movement of animals onto land

E) the origin of Hox genes and other genetic changes affecting the regulation of developmental genes

Answer 1

D) the movement of animals onto land

Question 2

Sponges are most accurately described as

A) aquatic predators.

B) freshwater scavengers.

C) aquatic filter feeders.

D) marine predators.

E) marine filter feeders.

Answer 2

C) aquatic filter feeders.

Question 3

Ecdysozoans:

A) have a body cavity that forms from the digestive system.

B) have trochophore larva.

C) include mollusks, annelids, and flatworms.

D) have a special feeding structure.

E) periodically shed their outer body covering.

Answer 3

E) periodically shed their outer body covering.

Question 4

________ are characterized by having a pseudocoelom.

A) Roundworms

B) Chordates

C) Arthropods

D) Annelids

E) Cnidarians

Answer 4

A) Roundworms

Question 5

The water vascular system of echinoderms

A) functions in locomotion and feeding.

B) is bilateral in organization, even though the adult animal is not bilaterally symmetrical.

C) moves water through the animal’s body during suspension feeding.

D) functions as a circulatory system that distributes nutrients to body cells.

E) is analogous to the gastrovascular cavity of flatworms.

Answer 5

A) functions in locomotion and feeding.

Question 6

At which developmental stage should one be able to first distinguish a protostome embryo from a deuterostome embryo?

A) coelom formation

B) gastrulation

C) cleavage

D) fertilization

E) metamorphosis

Answer 6

C) cleavage

Question 7

Which of the following is descriptive of protostomes?

A) spiral and determinate cleavage, blastopore becomes mouth

B) spiral and indeterminate cleavage, blastopore becomes mouth

C) spiral and determinate cleavage, blastopore becomes anus

D) radial and determinate cleavage, blastopore becomes anus

E) radial and determinate cleavage, blastopore becomes mouth

Answer 7

A) spiral and determinate cleavage, blastopore becomes mouth

Question 8

Both animals and fungi are heterotrophic. What distinguishes animal heterotrophy from fungal heterotrophy is that only animals derive their nutrition by

A) consuming living, rather than dead, prey.

B) ingesting it.

C) preying on animals.

D) using enzymes to digest their food.

Answer 8

B) ingesting it.

Question 9

In a tide pool, a student encounters an organism with a hard outer covering that contains much calcium carbonate, an open circulatory system, and gills. The organism could potentially be a crab, a shrimp, a barnacle, or a bivalve. The presence of which of the following structures would allow for the most certain identification of the organism?

A) a heart

B) eyes

C) a filter-feeding apparatus

D) a body cavity

E) a mantle

Answer 9

E) a mantle

Question 10

Which of the following combinations of phylum and description is incorrect?

A) Nematoda–roundworms, pseudocoelomate

B) Platyhelminthes–flatworms, gastrovascular cavity, acoelomate

C) Cnidaria–radial symmetry, polyp and medusa body forms

D) Porifera–gastrovascular cavity, coelom present

E) Echinodermata–bilateral symmetry as a larva, coelom present

Answer 10

D) Porifera–gastrovascular cavity, coelom present