Bio2 ch32- Animal Diversity

Which of the following is the most inclusive term for an organism that obtains organic food material by eating other organisms or substances derived from them?

heterotroph

producer

decomposer

autotroph

heterotroph

A mutualism is an ecological relationship between two species

a) in which one species benefits and the other is not harmed or helped in any significant way.

b) that live in close contact with each other.

c) that both benefit from the relationship.

d) in which the smaller species lives within the cells or body of the larger species (the host).

C

A graduate student finds an organism in a pond and thinks it is a freshwater sponge. A postdoctoral student thinks it looks more like an aquatic fungus. How can they decide whether it is an animal or a fungus?

a) Determine if it reproduces sexually.

b) Look for cell walls under a microscope.

c) Determine whether it is unicellular or multicellular.

d) Determine if it is a eukaryote or prokaryote.

B

Which of the following characteristics is unique to animals?

a) flagellated gametes

b) the structural carbohydrate, chitin

c) heterotrophy

d) nervous system signal conduction

D

The larvae of some insects are merely small versions of the adult, whereas the larvae of other insects look completely different from adults, eat different foods, and may live in different habitats. Which of the following is most directly involved in the evolution of these variations in metamorphosis?

a) the origin of a brain

b) artificial selection of sexually immature forms of insects

c) the evolution of meiosis

d) changes in the homeobox genes controlling early development

D

Both animals and fungi are heterotrophic. Which of the following distinguishes animal heterotrophy from fungal heterotrophy?

a) most animals derive their nutrition by preying on other animals

b) most animals derive their nutrition by consuming living, rather than dead, prey

c) most animals derive their nutrition by ingesting materials

d) most animals derive their nutrition by using enzymes to digest their food

C

In individual insects of some species, whole chromosomes that carry larval genes are eliminated from the genomes of somatic cells at the time of metamorphosis. As a result of the chromosome loss, which of the following consequences is most likely?

a) metamorphosis can no longer occur among the descendants of such adults

b) sequencing of the entire genome will not be possible

c) cloning a larva from the somatic cells of such an adult insect would be difficult

d) such species must reproduce only asexually

C

All animals can trace their lineage to a common ancestor that lived in the _____.

Jurassic

Neoproterozoic

Cenozoic

Devonian

Neoproterozoic

The earliest ancestors of about half of all extant animal phyla can be traced back to the __________ explosion.

Jurassic

Devonian

Carboniferous

Cambrian

Cambrian

Which of the following organisms was most likely the most recent common ancestor of all animals?

a) multicellular fungus

b) flagellated protist

c) unicellular chytrid

d) multicellular algae

B

Evidence of which structure or characteristic would be rare to find among fossils of the Ediacaran fauna?

a) hard parts

b) embryos

c) bilateral symmetry

d) true tissues

A

Which of the following factors most likely contributed to the extinction of many Ediacaran life forms?

a) predation by new species, poisoning from high oxygen levels, and loss of habitat due to increased temperatures

b) predation by new species, faster movement by new species, and increased developmental flexibility by new species

c) loss of habitat due to increased temperatures, poisoning from high oxygen levels, and loss of developmental flexibility

d) predation by new species, poisoning from high carbon dioxide levels, and loss of developmental flexibility

B

Which of the following is radially symmetrical?

An automobile

A dog

A spoon

A doughnut

A doughnut

Gastrulation is the process that directly forms the __________.

organs

germ layers

blastula

central nervous system

germ layers

Sponges share many similarities with the protists called __________.

radiolarians

choanoflagellates

dinoflagellates

euglenids

choanoflagellates

All of the following animals have a body cavity except for which one?

Clam

Nematode

Earthworm

Flatworm

Flatworm

Which tissue type or organ is correctly matched with its germ layer tissue?

a) nervous——mesoderm

b) muscular——ectoderm

c) skin——ectoderm

d) stomach——mesoderm

C

Which of the following is a feature of the digestive tube in most animal phyla?

a) The two "tubes" are separated by tissue that comes from embryonic endoderm.

b) The outer tube consists of digestive organs.

c) The mouth and anus form the ends of the inner tube.

d) The outer tube consists of a hard exoskeleton.

C

Among organisms exhibiting triploblastic development, which morphological trait shows the most variation?

a) type of symmetry

b) type of cell cleavage

c) type of body cavity

d) number of embryonic tissue types

C

Soon after the coelom begins to form, a researcher injects a dye into the coelom of a deuterostome embryo. Into which of the following structures would you expect the dye to flow?

hemocoel

blastocoelom

archenteron

blastopore

archenteron

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° and to lie in the grooves between larger, underlying cells. If we were to separate these eight cells and attempt to culture them individually, then what is most likely to happen?

a) All eight cells will die immediately.

b) Each cell may develop into a smaller-than-average, but otherwise normal, embryo.

c) Each cell may develop into a full-sized, normal embryo.

d) Each cell may continue development, but only into a nonviable embryo that lacks many parts.

D

Which of the following was an early selective advantage of a coelom in animals?

a) It was a more efficient digestive system.

b) It contains fluid which cushions the internal organs from damage.

c) It allowed cephalization and the formation of a cerebral ganglion.

d) It allowed asexual and sexual reproduction.

B

If an organism exhibits a head with sensory structures, which of the following characteristics would it likely also exhibit?

a) It is diploblastic.

b) It is segmented.

c) It has a coelom.

d) It is bilaterally symmetrical.

D

Suppose a researcher for a pest-control company developed a chemical that inhibited the development of an embryonic mosquito's endodermal cells. Which of the following best explains the effectiveness of the pesticide?

a) The mosquito would have trouble digesting food, due to impaired gut function.

b) The mosquito would develop a weakened exoskeleton that would make it vulnerable to trauma.

c) The mosquito wouldn't be affected at all.

d) The mosquito would have trouble with respiration and circulation, due to impaired muscle function.

A

Which of the following characteristics represents the oldest branch point in animal phylogeny?

a) true tissues or no tissues

b) diploblastic or triploblastic embryos

c) radial or bilateral symmetry

d) a body cavity or no body cavity

A

Which of the following statements is correct regarding animal body plans?

a) organisms direct their own evolution in order to maximize their success

b) the body plans we see now have been evolutionarily advantageous compared to others in the past

c) mutations have arisen that allow only some shapes to be produced

d) animals evolve according to a pre-ordained plan

B

Nine-banded armadillos give birth to four genetically identical offspring at a time. What does this fact suggest about the development of these organisms?

a) the embryo undergoes radial and indeterminate cleavage

b) the young undergo metamorphosis

c) the species has a hemocoel

d) the first cell division of the fertilized egg is perpendicular to the vertical axis of the egg

A

Select the correct statement(s) about animal body plans.

Select all that apply.

a) Development in all animals is determined by the unique family of Hox genes (or other similar homeobox genes).

b) In both protostomes and deuterostomes, the blastopore develops into the mouth.

c) All triploblastic animals possess a coelom.

A only

Which feature of deuterostome development explains the formation of identical human twins?

a) Deuterostomes have indeterminate development.

b) Deuterostomes have radial cleavage.

c) In deuterostomes, the blastopore becomes the anus.

A

Which of the following statements is correct?

a) Eumetazoans have three embryonic tissue layers.

b) All animals share a common ancestor.

c) The origin of all extant animal phyla can be traced to the Cambrian explosion.

d) Sponges are diploblastic animals.

B

You find a new species of worm and want to classify it. Which of the following lines of evidence would allow you to classify the worm as a nematode and not an annelid?

a) It sheds its external skeleton to grow.

b) It is triploblastic.

c) It has a coelom.

d) It is segmented.

A

Some researchers claim that sponge genomes have homeotic genes, but no Hox genes. If true, how would this impact the phylogenetic tree of animals?

a) sponges must no longer be classified as animals

b) it would confirm the identity of sponges as "basal animals"

c) extinct sponges must have been the last common ancestor of animals and fungi

d) it would require sponges to be reclassified as choanoflagellates

B

Which of the following statements concerning animal taxonomy is accurate?

a) In the kingdom Animalia, most clades based on body plan confirm clades based on molecular data.

b) Animals are thought to have evolved from flagellated protists similar to modern choanoflagellates.

c) Animals are more closely related to plants than to fungi.

d) Kingdom Animalia is polyphyletic.

B

At one time, sponges were lumped into one phylum. Then, they were separated into several different phyla. Now, they are considered one phylum again. These changes indicate which of the following?

a) The goal of making all taxonomic groups monophyletic is unrealistic.

b) We need more fossil evidence of sponges.

c) Molecular and morphological data often conflict when we try to reconstruct evolutionary history.

d) Every phylogeny should be considered a hypothesis that must be revised in the light of new data.

D

Placing sponges as the basal metazoans on the basis of lack of tissues implies which of the following?

a) Sponges do not have nerve cells.

b) Modern-day sponges have lost the ability to form tissues.

c) Sponge ancestors never had tissues.

d) Multicellular, modern-day choanoflagellates can form tissues.

C

Select the correct statement about the evolution of animals.

a) Approximately half the phyla of living organisms are found in Cambrian sediments.

b) No animal fossils are found in strata formed before the Cambrian explosion.

c) The oldest generally accepted fossils of large animals range in age from 565 to 550 million years old.

C

Identify the features that distinguish animals from organisms in other multicellular kingdoms.

Select all that apply.

a) Animals are ingestive heterotrophs.

b) Animals have sensory organs at their anterior end.

c) Animals are motile.

A only