Question 1

Which of the following is considered a likely explanation for the events of the Cambrian explosion?

Accepted Answer

A)  Complex predator-prey relationships and increased atmospheric oxygen levels promoted animal diversification. 
B)  A great surge of volcanic activity was triggered by significant movements of the continental plates and possibly by an asteroid impact. 
C)  Solar flares led to increased UV radiation intensity, which in turn promoted a high rate of mutation. This led to rapid diversification of animals. 
D)  The massive growth of swamp vegetation depleted the atmosphere's carbon dioxide and eventually cooled the Earth's climate. 
A)  Complex predator-prey relationships and increased atmospheric oxygen levels promoted animal diversification. 
B)  A great surge of volcanic activity was triggered by significant movements of the continental plates and possibly by an asteroid impact. 
C)  Solar flares led to increased UV radiation intensity, which in turn promoted a high rate of mutation. This led to rapid diversification of animals. 
D)  The massive growth of swamp vegetation depleted the atmosphere's carbon dioxide and eventually cooled the Earth's climate. A

Question 2

You inflate a balloon and let it go. It shoots away as air exits forcefully through the balloon's narrow opening. This most closely resembles the mode of movement seen in

Accepted Answer

A)  sea anemones. 
B)  snails. 
C)  squid. 
D)  nematodes. 
A)  sea anemones. 
B)  snails. 
C)  squid. 
D)  nematodes. C

Question 3

Animals directly evolved from

Accepted Answer

A)  plants. 
B)  protists. 
C)  fungi. 
D)  bacteria. 
A)  plants. 
B)  protists. 
C)  fungi. 
D)  bacteria. B

Question 4

A dog's head is at its ________ end, and its belly is its ________ surface.

Accepted Answer

A)  posterior; dorsal 
B)  anterior; dorsal 
C)  posterior; ventral 
D)  anterior; ventral 
A)  posterior; dorsal 
B)  anterior; dorsal 
C)  posterior; ventral 
D)  anterior; ventral

Question 5

Which of the following is an invertebrate chordate?

Accepted Answer

A)  lancelets 
B)  snakes 
C)  sharks 
D)  sea urchins 
A)  lancelets 
B)  snakes 
C)  sharks 
D)  sea urchins

Question 6

Most adult insects have three major body parts or sections. They are the

Accepted Answer

A)  head, body, and legs. 
B)  head, thorax, and abdomen. 
C)  antennae, head, and abdomen. 
D)  legs, wings, and body. 
A)  head, body, and legs. 
B)  head, thorax, and abdomen. 
C)  antennae, head, and abdomen. 
D)  legs, wings, and body.

Question 7

Suppose that the bottom of an ocean floor is disrupted, and bits of algae along with other bottom-dwelling microorganisms are scattered about into the ocean water. Which organism would be able to take the best advantage of this temporary food source?

Accepted Answer

A)  sponges 
B)  cnidarians 
C)  parasitic flatworms 
D)  soil-dwelling nematodes 
A)  sponges 
B)  cnidarians 
C)  parasitic flatworms 
D)  soil-dwelling nematodes

Question 8

While walking in your basement, you hear a crunching noise and notice that you have stepped on an organism. You look closely and see part of a segmented body and a few jointed appendages. What phylum does this animal represent?

Accepted Answer

A)  Echinodermata 
B)  Annelida 
C)  Arthropoda 
D)  Chordata 
A)  Echinodermata 
B)  Annelida 
C)  Arthropoda 
D)  Chordata

Question 9

The locomotive behavior of earthworms is enabled by contraction of their longitudinal and circular muscles; this is seen through their typical burrowing behavior. Nematodes, however, contract their longitudinal muscles against the pressure of fluid in their bodies to produce a whiplike motion that enables them to move. Suppose you place an earthworm and a nematode in a watery solution. Which do you think would be able to move more easily, and why?

Accepted Answer

A)  the earthworm, because it uses two sets of muscles to help it move through the watery solution 
B)  the nematode, because its whiplike motion will easily propel it through the watery solution 
C)  the earthworm, because it can contract and expand its muscles to burrow down through the watery solution 
D)  the nematode, because it can move its paddle-like appendages on its segments to help it move through the watery solution 
A)  the earthworm, because it uses two sets of muscles to help it move through the watery solution 
B)  the nematode, because its whiplike motion will easily propel it through the watery solution 
C)  the earthworm, because it can contract and expand its muscles to burrow down through the watery solution 
D)  the nematode, because it can move its paddle-like appendages on its segments to help it move through the watery solution

Question 10

The flexible, longitudinal rod that is located between the digestive tract and the nerve cord in chordates is called the

Accepted Answer

A)  spinal cord. 
B)  notochord. 
C)  dorsal, hollow nerve cord. 
D)  spine. 
A)  spinal cord. 
B)  notochord. 
C)  dorsal, hollow nerve cord. 
D)  spine.

Question 11

Which of the following statements is true?

Accepted Answer

A)  Arthropods have an open circulatory system, while annelids have a closed circulatory system. 
B)  Vertebrates have an open circulatory system, while annelids have a closed circulatory system. 
C)  Vertebrates have an open circulatory system, while arthropods have a closed circulatory system. 
D)  Annelids have an open circulatory system, while molluscs have a closed circulatory system. 
A)  Arthropods have an open circulatory system, while annelids have a closed circulatory system. 
B)  Vertebrates have an open circulatory system, while annelids have a closed circulatory system. 
C)  Vertebrates have an open circulatory system, while arthropods have a closed circulatory system. 
D)  Annelids have an open circulatory system, while molluscs have a closed circulatory system.

Question 12

The ________ is a flagellated cell that sweeps water through a sponge's body.

Accepted Answer

A)  choanocyte 
B)  amoebocyte 
C)  spicule 
D)  spongin 
A)  choanocyte 
B)  amoebocyte 
C)  spicule 
D)  spongin

Question 13

All animals

Accepted Answer

A)  are prokaryotic. 
B)  are heterotrophic. 
C)  have cell walls made of chitin. 
D)  obtain food by absorption. 
A)  are prokaryotic. 
B)  are heterotrophic. 
C)  have cell walls made of chitin. 
D)  obtain food by absorption.

Question 14

Typical animal embryos have a(n) ________, or external cell layer, and a(n) ________, which lines the digestive tract.

Accepted Answer

A)  ectoderm; blastula 
B)  ectoderm; endoderm 
C)  endoderm; ectoderm 
D)  mesoderm; gastrula 
A)  ectoderm; blastula 
B)  ectoderm; endoderm 
C)  endoderm; ectoderm 
D)  mesoderm; gastrula

Question 15

Which of these molluscs commonly have a hinged shell?

Accepted Answer

A)  gastropods only 
B)  bivalves only 
C)  cephalopods only 
D)  gastropods and bivalves 
A)  gastropods only 
B)  bivalves only 
C)  cephalopods only 
D)  gastropods and bivalves

Question 16

Organisms with true radial symmetry

Accepted Answer

A)  have their sense organs, mouth, and brain clustered in the head. 
B)  tend to be highly mobile. 
C)  do not have a distinct head region and tend to be sedentary or passive drifters. 
D)  can be divided into two matching halves along only one plane. 
A)  have their sense organs, mouth, and brain clustered in the head. 
B)  tend to be highly mobile. 
C)  do not have a distinct head region and tend to be sedentary or passive drifters. 
D)  can be divided into two matching halves along only one plane.

Question 17

Animals that are segmented and have jointed appendages and an exoskeleton are members of the phylum

Accepted Answer

A)  Platyhelminthes. 
B)  Annelida. 
C)  Cnidaria. 
D)  Arthropoda. 
A)  Platyhelminthes. 
B)  Annelida. 
C)  Cnidaria. 
D)  Arthropoda.

Question 18

According to recent genetic research, the complexity of an organism

Accepted Answer

A)  is directly correlated with the number of protein-coding genes in its genome. 
B)  is inversely related to the number of protein-coding genes in its genome. 
C)  has more to do with how genes are used or regulated than with which genes are present. 
A)  is directly correlated with the number of protein-coding genes in its genome. 
B)  is inversely related to the number of protein-coding genes in its genome. 
C)  has more to do with how genes are used or regulated than with which genes are present.

Question 19

The most numerous, diverse, and widespread animals are the

Accepted Answer

A)  Arthropoda. 
B)  Mollusca. 
C)  Annelida. 
D)  Chordata. 
A)  Arthropoda. 
B)  Mollusca. 
C)  Annelida. 
D)  Chordata.

Question 20

The graph below is of an index of diversity of arthropods in three different plots of a cornfield. In one of the three plots an insecticide was sprayed. Answer the questions below about this situation.
   Arthropod diversity in three cornfield plots.
-When and where does it appear that the insecticide was applied?

Accepted Answer

A)  in August in Plot 3 
B)  in July in Plot 3 
C)  in June in Plot 1 
D)  in May in Plot 1 
A)  in August in Plot 3 
B)  in July in Plot 3 
C)  in June in Plot 1 
D)  in May in Plot 1

Exam 18: The Evolution of Invertebrate Diversity

Which of the following is considered a likely explanation for the events of the Cambrian explosion?

You inflate a balloon and let it go. It shoots away as air exits forcefully through the balloon's narrow opening. This most closely resembles the mode of movement seen in

Animals directly evolved from

A dog's head is at its ________ end, and its belly is its ________ surface.

Which of the following is an invertebrate chordate?

Most adult insects have three major body parts or sections. They are the

Suppose that the bottom of an ocean floor is disrupted, and bits of algae along with other bottom-dwelling microorganisms are scattered about into the ocean water. Which organism would be able to take the best advantage of this temporary food source?

While walking in your basement, you hear a crunching noise and notice that you have stepped on an organism. You look closely and see part of a segmented body and a few jointed appendages. What phylum does this animal represent?

The flexible, longitudinal rod that is located between the digestive tract and the nerve cord in chordates is called the

Which of the following statements is true?

The ________ is a flagellated cell that sweeps water through a sponge's body.

All animals

Typical animal embryos have a(n) ________, or external cell layer, and a(n) ________, which lines the digestive tract.

Which of these molluscs commonly have a hinged shell?

Organisms with true radial symmetry

Animals that are segmented and have jointed appendages and an exoskeleton are members of the phylum

According to recent genetic research, the complexity of an organism

The most numerous, diverse, and widespread animals are the

Biology: Exploring Life

The Chemical Basis of Life

The Molecules of Cells

A Tour of the Cell

The Working Cell

How Cells Harvest Chemical Energy

Photosynthesis: Using Light to Make Food

The Cellular Basis of Reproduction and Inheritance

Patterns of Inheritance

Molecular Biology of the Gene

How Genes Are Controlled

DNA Technology and Genomics

How Populations Evolve

The Origin of Species

Tracing Evolutionary History

Microbial Life: Prokaryotes and Protists

The Evolution of Plant and Fungal Diversity

The Evolution of Vertebrate Diversity

Unifying Concepts of Animal Structure and Function

Nutrition and Digestion

Gas Exchange

Circulation

The Immune System

Control of Body Temperature and Water Balance

Hormones and the Endocrine System

Reproduction and Embryonic Development

Nervous Systems

The Senses

How Animals Move

Plant Structure, Growth, and Reproduction

Plant Nutrition and Transport

Control Systems in Plants

The Biosphere: an Introduction to Earths Diverse Environments

Behavioral Adaptations to the Environment

Population Ecology

Communities and Ecosystems

Conservation Biology

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A dog's head is at its end, and its belly is its surface.

Typical animal embryos have a(n) , or external cell layer, and a(n) , which lines the digestive tract.