Chapter 32

Which of the following statements concerning animal taxonomy is (are) true? 1. Animals are more closely related to plants than to fungi. 2. All animal clades based on body plan have been found to be incorrect. 3. Kingdom Animalia is monophyletic. 4. Only animals reproduce by sexual means. 5. Animals are thought to have evolved from flagellated protists similar to modern choanoflagellates. a. 3, 5 b. 1, 3 c. 3, 4, 5 d. 5 e. 2, 4

a. 3, 5

An animal that swims rapidly in search of prey that it captures using visual senses concentrated at its anterior end is likely to be A. bilaterally symmetrical and cephalized B. coelomate and a protostome. C. eumetazoan and asymmetrical. D. diploblastic and radially symmetrical. E. heterotrophic and sessile

A. bilaterally symmetrical and cephalized

The following questions are based on the description below. A student encounters an animal embryo at the eight-cell stage. The four smaller cells that comprise one hemisphere of the embryo seem to be rotated 45 degrees and lie in the grooves between larger, underlying cells (spiral cleavage). This embryo may potentially develop into a(n) A. earthworm B. sea star C. turtle D. fish E. sea urchin

A. earthworm

Among the characteristics unique to animals is A. gastrulation B. heterotrophic nutrition C. flagellated sperm D. multicellularity E. sexual reproduction.

A. gastrulation

Flatworms are similar to cnidarians in that both ______. A. have pseudocoeloms B. have true tissues C. lack a gastrovascular cavity D. exhibit bilateral symmetry E. include many parasitic species

B. Have true tissues

A true coelom is ______. A. formed when a zygote develops into a blastula B. completely lined with tissue derived from mesoderm C. formed when a larva undergoes metamorphosis D. completely lined with tissue derived from endoderm E. completely lined with tissue derived from ectoderm

B. completely lined with tissue derived from mesoderm

What is the name given to the process by which a larva develops into an adult? A. neurulation B. metamorphosis C. morphogenesis D. gastrulation E. organogenesis

B. metamorphosis

Which of the following functions is an advantage of a fluid-filled body cavity? A. Internal organs are cushioned and protected from injury. B. The fluid within the cavity acts as a hydrostatic skeleton. C. all of the answers are correct D. Organs can grow and move independently of the outer body wall.

C. All of the answers are correct

Sponges and cnidarians are among the fossilized animals found in both the Ediacara Hills and the Burgess Shale from the Rocky Mountains of British Colombia. This observation requires that A. North America and Australia were united to each other about 550 million years ago (mya). B. only sponges and cnidarians existed at the time the sediments were deposited C. ancestral sponges and cnidarians had formerly been terrestrial animals. D. land that now comprises the Ediacara Hills and the Rocky Mountains was underwater about 550 million years ago.

D. land that now comprises the Ediacara Hills and the Rocky Mountains was underwater about 550 million years ago.

A student encounters an animal embryo at the eight-cell stage. The four smaller cells that comprise one hemisphere of the embryo seem to be rotated 45 degrees and lie in the grooves between larger, underlying cells (spiral cleavage). If an undisturbed embryo is allowed to develop further, then one should expect that A. upon gastrulation, a solid ball of cells will be produced. B. upon metamorphosis, the resulting trochophore larva will gain a backbone. C. all of the answers are correct. D. the first opening of the gastrula will ultimately serve as the mouth.

D. the first opening of the gastrula will ultimately serve as the mouth.

At which developmental stage should one be able to first distinguish a protostome embryo from a deuterostome embryo? a. cleavage b. coelom formation c. gastrulation d. fertilization e. metamorphosis

a. cleavage

Which of the following is a correct association of an animal germ layer with the tissues or organs to which it gives rise? a. endoderm: linings of liver passageways and lung passageways b. ectoderm: outer covering of digestive system c. mesoderm: skin d. endoderm: internal lining of blood vessels e. mesoderm: central nervous system

a. endoderm: linings of liver passageways and lung passageways

The common ancestor of all animals is likely to have been a(n) ______. a. sponge b. colonial, flagellated protist c. colonial, flagellated moneran d. colonial, ciliated protist e. apicomplexan

b. colonial, flagellated protist

What is characteristic of all ecdysozoans? a. the diploblastic condition b. some kind of exoskeleton, or hard outer covering c. a pseudocoelom d. agile, speedy, and powerful locomotion e. the deuterostome condition

b. some kind of exoskeleton, or hard outer covering

Humans are chordates. Which animal group is most closely related to chordates? a. annelids b. arthropods c. echinoderms d. cnidarians e. mollusks

c. echinoderms

What is the correct sequence of the following four events during an animal's development? 1. gastrulation 2. metamorphosis 3. fertilization 4. cleavage a. 3 → 4 → 2 → 1 b. 3 → 2 → 4 → 1 c. 4 → 3 → 1 → 2 d. 3 → 4 → 1 → 2 e. 4 → 3 → 2 → 1

d. 3 → 4 → 1 → 2

Cephalization is primarily associated with a. type of digestive system. b. adaptation to dark environments. c. fate of the blastopore. d. bilateral symmetry. e. method of reproduction.

d. bilateral symmetry

Which of the following characteristics generally applies to protostome development? a. diploblastic embryo b. archenteron absent c. radial cleavage d. determinate cleavage e. blastopore becomes the anus

d. determinate cleavage

How do sponges differ from all other animals? a. Sponges have a true coelom. b. Sponges exhibit radial symmetry. c. Sponges are autotrophs. d. Sponges lack a true body cavity. e. Sponges lack true tissues.

e. Sponges lack true tissues

What type of symmetry does this organism (jellyfish) exhibit? a. binomial b. asymmetrical c. terrestrial d. bilateral e. radial

e. radial