Question 1

Which of the following statements is correct?

Accepted Answer

A) Most animals contain Hox genes, with the exception of sponges 
B) Fungi and animals are heterotrophs that ingest their food 
C) Most animals reproduce sexually and asexually 
D) In most animals, cleavage produces a multicellular stage called a gastrula 
E) B and C 
A) Most animals contain Hox genes, with the exception of sponges 
B) Fungi and animals are heterotrophs that ingest their food 
C) Most animals reproduce sexually and asexually 
D) In most animals, cleavage produces a multicellular stage called a gastrula 
E) B and C A

Question 2

What is the correct sequence (from most ancient to most recent)of milestones in the evolution of animals?

Accepted Answer

A) choanoflagellates, Ediacaran biota, Cambrian explosion, successful invasion of land, origin of flight 
B) choanoflagellates, Cambrian explosion, Ediacaran biota, successful invasion of land, origin of flight 
C) Ediacaran biota, choanoflagellates, Cambrian explosion, successful invasion of land, origin of flight 
D) Cambrian explosion, choanoflagellates, Ediacaran biota, successful invasion of land, origin of flight 
E) choanoflagellates, Cambrian explosion, successful invasion of land, Ediacaran biota, origin of flight 
A) choanoflagellates, Ediacaran biota, Cambrian explosion, successful invasion of land, origin of flight 
B) choanoflagellates, Cambrian explosion, Ediacaran biota, successful invasion of land, origin of flight 
C) Ediacaran biota, choanoflagellates, Cambrian explosion, successful invasion of land, origin of flight 
D) Cambrian explosion, choanoflagellates, Ediacaran biota, successful invasion of land, origin of flight 
E) choanoflagellates, Cambrian explosion, successful invasion of land, Ediacaran biota, origin of flight A

Question 3

Which of the following genetic processes may be most helpful in accounting for the Cambrian explosion?

Accepted Answer

A) binary fission 
B) mitosis 
C) random segregation 
D) gene duplication 
E) chromosomal condensation 
A) binary fission 
B) mitosis 
C) random segregation 
D) gene duplication 
E) chromosomal condensation D

Question 4

Which of these,if true,would support the claim that the ancestral cnidarians had bilateral symmetry?
1)Cnidarian larvae possess anterior-posterior,left-right,and dorsal-ventral aspects.
2)Cnidarians have fewer Hox genes than bilaterians.
3)All extant cnidarians,including Nematostella,are diploblastic.
4)β-catenin turns out to be essential for gastrulation in all animals in which it occurs.
5)All cnidarians are acoelomate.

Accepted Answer

A) 1 only 
B) 1 and 4 
C) 2 and 3 
D) 2 and 4 
E) 4 and 5 
A) 1 only 
B) 1 and 4 
C) 2 and 3 
D) 2 and 4 
E) 4 and 5

Question 5

A researcher is trying to construct a molecular-based phylogeny of the entire animal kingdom.Assuming that none of the following genes is absolutely conserved,which of the following would be the best choice on which to base the phylogeny?

Accepted Answer

A) genes involved in chitin synthesis 
B) collagen genes 
C) β-catenin genes 
D) genes involved in eye-lens synthesis 
E) genes that cause radial body symmetry 
A) genes involved in chitin synthesis 
B) collagen genes 
C) β-catenin genes 
D) genes involved in eye-lens synthesis 
E) genes that cause radial body symmetry

Question 6

The evolution of animal species has been prolific (the estimates go into the millions and tens of millions).Much of this diversity is a result of the evolution of novel ways to ________.

Accepted Answer

A) reproduce 
B) arrange cells into tissues 
C) sense, feed, and move 
D) form an embryo and establish a basic body plan 
A) reproduce 
B) arrange cells into tissues 
C) sense, feed, and move 
D) form an embryo and establish a basic body plan

Question 7

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

Accepted Answer

A) preying on animals. 
B) ingesting it. 
C) consuming living, rather than dead, prey. 
D) using enzymes to digest their food. 
A) preying on animals. 
B) ingesting it. 
C) consuming living, rather than dead, prey. 
D) using enzymes to digest their food.

Question 8

In its native environment,a Tp cell neither gains nor loses water.What should one expect to occur when Tp is placed into fresh water?

Accepted Answer

A) No change, as fresh water is its native environment 
B) lysis 
C) plasmolysis 
D) slight shrinkage 
A) No change, as fresh water is its native environment 
B) lysis 
C) plasmolysis 
D) slight shrinkage

Question 9

What criteria differentiates a pseudocoelomate versus a coelomate animal?

Accepted Answer

A) A pseudocoelomate animal is diploblastic and the body cavity is partially lined by endoderm. 
B) A pseudocoelomate animal is diploblastic and the body cavity is completely lined by mesoderm. 
C) A coelomate animal is triploblastic and the body cavity is completely lined by mesoderm. 
D) A coelomate animal is triploblastic and the body cavity is completely lined by endoderm. 
E) A coelomate animal is diploblastic and the body cavity is completely lined by mesoderm. 
A) A pseudocoelomate animal is diploblastic and the body cavity is partially lined by endoderm. 
B) A pseudocoelomate animal is diploblastic and the body cavity is completely lined by mesoderm. 
C) A coelomate animal is triploblastic and the body cavity is completely lined by mesoderm. 
D) A coelomate animal is triploblastic and the body cavity is completely lined by endoderm. 
E) A coelomate animal is diploblastic and the body cavity is completely lined by mesoderm.

Question 10

The last common ancestor of all bilaterians is thought to have had four Hox genes.Most extant cnidarians have two Hox genes,except Nematostella (of β-catenin fame),which has three Hox genes.On the basis of these observations,some have proposed that the ancestral cnidarians were originally bilateral and,in stages,lost Hox genes from their genomes.If true,this would mean that

Accepted Answer

A) Radiata should be a true clade. 
B) the radial symmetry of extant cnidarians is secondarily derived, rather than being an ancestral trait. 
C) Hox genes play little actual role in coding for an animal's "body plan." 
D) Cnidaria may someday replace Acoela as the basal bilaterians. 
E) Two of the responses above are correct. 
A) Radiata should be a true clade. 
B) the radial symmetry of extant cnidarians is secondarily derived, rather than being an ancestral trait. 
C) Hox genes play little actual role in coding for an animal's "body plan." 
D) Cnidaria may someday replace Acoela as the basal bilaterians. 
E) Two of the responses above are correct.

Question 11

Which of these,if discovered among cycliophorans,would cause the most confusion concerning our current understanding of cycliophoran taxonomy?

Accepted Answer

A) if the ciliated feeding ring is a lophophore 
B) if embryos are diploblastic 
C) if the body cavity is actually a pseudocoelom 
D) if the organisms show little apparent cephalization 
A) if the ciliated feeding ring is a lophophore 
B) if embryos are diploblastic 
C) if the body cavity is actually a pseudocoelom 
D) if the organisms show little apparent cephalization

Question 12

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 would be a likely mechanism by which this pesticide works?

Accepted Answer

A) The mosquito would develop a weakened exoskeleton that would make it vulnerable to trauma. 
B) The mosquito would have trouble digesting food, due to impaired gut function. 
C) The mosquito would have trouble with respiration and circulation, due to impaired muscle function. 
D) The mosquito wouldn't be affected at all. 
A) The mosquito would develop a weakened exoskeleton that would make it vulnerable to trauma. 
B) The mosquito would have trouble digesting food, due to impaired gut function. 
C) The mosquito would have trouble with respiration and circulation, due to impaired muscle function. 
D) The mosquito wouldn't be affected at all.

Question 13

In examining an unknown animal species during its embryonic development,how can you be sure what you are looking at is a protostome and not a deuterostome?

Accepted Answer

A) There is evidence of cephalization. 
B) The animal is triploblastic. 
C) The animal is clearly bilaterally symmetrical. 
D) You see a mouth, but not an anus. 
A) There is evidence of cephalization. 
B) The animal is triploblastic. 
C) The animal is clearly bilaterally symmetrical. 
D) You see a mouth, but not an anus.

Question 14

Some researchers claim that sponge genomes have homeotic genes,but no Hox genes.If true,this finding would

Accepted Answer

A) strengthen sponges' evolutionary ties to the Eumetazoa. 
B) mean that sponges must no longer be classified as animals. 
C) confirm the identity of sponges as "basal animals." 
D) mean that extinct sponges must have been the last common ancestor of animals and fungi. 
E) require sponges to be reclassified as choanoflagellates. 
A) strengthen sponges' evolutionary ties to the Eumetazoa. 
B) mean that sponges must no longer be classified as animals. 
C) confirm the identity of sponges as "basal animals." 
D) mean that extinct sponges must have been the last common ancestor of animals and fungi. 
E) require sponges to be reclassified as choanoflagellates.

Question 15

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?

Accepted Answer

A) It is segmented. 
B) It is triploblastic. 
C) It has a coelom. 
D) It sheds its external skeleton to grow. 
A) It is segmented. 
B) It is triploblastic. 
C) It has a coelom. 
D) It sheds its external skeleton to grow.

Question 16

The following questions refer to the description below.
You have taken an introductory course in animal biology and know that animals have evolved with different types of symmetry.Animals that show radial symmetry have a top and bottom,but do not have a left or right side,nor a front or back end.Animals that show bilateral symmetry have a top and bottom,left and right sides,and distinct anterior and posterior ends.
-Why do you think that evolution of cephalization is correlated with the evolution of bilateral symmetry?

Accepted Answer

A) Bilaterally symmetrical animals are better adapted in aquatic environments where animals first evolved. 
B) As organisms needed to get smarter, an anterior end with a head region evolved. 
C) Bilaterally symmetrical animals have an anterior end that contains sensory material/brain region. 
D) If animals want to move backward, they need to have a front and back end. 
E) Two of the above are correct. 
A) Bilaterally symmetrical animals are better adapted in aquatic environments where animals first evolved. 
B) As organisms needed to get smarter, an anterior end with a head region evolved. 
C) Bilaterally symmetrical animals have an anterior end that contains sensory material/brain region. 
D) If animals want to move backward, they need to have a front and back end. 
E) Two of the above are correct.

Question 17

Acoelomates are characterized by

Accepted Answer

A) the absence of a brain. 
B) the absence of mesoderm. 
C) deuterostome development. 
D) a coelom that is not completely lined with mesoderm. 
E) a solid body without a cavity surrounding internal organs. 
A) the absence of a brain. 
B) the absence of mesoderm. 
C) deuterostome development. 
D) a coelom that is not completely lined with mesoderm. 
E) a solid body without a cavity surrounding internal organs.

Question 18

Which statement is most consistent with the hypothesis that the Cambrian explosion was caused by the rise of predator-prey relationships?

Accepted Answer

A) increased incidence of worm burrows in the fossil record 
B) increased incidence of larger animals in the fossil record 
C) increased incidence of organic material in the fossil record 
D) increased incidence of fern galls in the fossil record 
E) increased incidence of hard parts in the fossil record 
A) increased incidence of worm burrows in the fossil record 
B) increased incidence of larger animals in the fossil record 
C) increased incidence of organic material in the fossil record 
D) increased incidence of fern galls in the fossil record 
E) increased incidence of hard parts in the fossil record

Question 19

The Hox genes came to regulate each of the following in what sequence,from earliest to most recent?
1)identity and position of paired appendages in protostome embryos
2)anterior-posterior orientation of segments in protostome embryos
3)positioning of tentacles in cnidarians
4)anterior-posterior orientation in vertebrate embryos

Accepted Answer

A) 4 → 1 → 3 → 2 
B) 4 → 2 → 3 → 1 
C) 4 → 2 → 1 → 3 
D) 3 → 2 → 1 → 4 
E) 3 → 4 → 1 → 2 
A) 4 → 1 → 3 → 2 
B) 4 → 2 → 3 → 1 
C) 4 → 2 → 1 → 3 
D) 3 → 2 → 1 → 4 
E) 3 → 4 → 1 → 2

Question 20

The blastopore is a structure that first becomes evident during

Accepted Answer

A) fertilization. 
B) gastrulation. 
C) the eight-cell stage of the embryo. 
D) coelom formation. 
E) cleavage. 
A) fertilization. 
B) gastrulation. 
C) the eight-cell stage of the embryo. 
D) coelom formation. 
E) cleavage.

Exam 32: An Overview of Animal Diversity

Which of the following statements is correct?

What is the correct sequence (from most ancient to most recent)of milestones in the evolution of animals?

Which of the following genetic processes may be most helpful in accounting for the Cambrian explosion?

A researcher is trying to construct a molecular-based phylogeny of the entire animal kingdom.Assuming that none of the following genes is absolutely conserved,which of the following would be the best choice on which to base the phylogeny?

The evolution of animal species has been prolific (the estimates go into the millions and tens of millions).Much of this diversity is a result of the evolution of novel ways to ________.

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

In its native environment,a Tp cell neither gains nor loses water.What should one expect to occur when Tp is placed into fresh water?

What criteria differentiates a pseudocoelomate versus a coelomate animal?

Which of these,if discovered among cycliophorans,would cause the most confusion concerning our current understanding of cycliophoran taxonomy?

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 would be a likely mechanism by which this pesticide works?

In examining an unknown animal species during its embryonic development,how can you be sure what you are looking at is a protostome and not a deuterostome?

Some researchers claim that sponge genomes have homeotic genes,but no Hox genes.If true,this finding would

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?

Acoelomates are characterized by

Which statement is most consistent with the hypothesis that the Cambrian explosion was caused by the rise of predator-prey relationships?

The blastopore is a structure that first becomes evident during

Introduction: Evolution and Themes of Biology

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure,Growth,and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons,Synapses,and Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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