Question 1

When considering the wormlike phyla within the protostomes, which feature is most useful in distinguishing groups?

Accepted Answer

A)  the presence of a mouth 
B)  the presence or absence of a complete digestive system 
C)  molting as they grow larger 
D)  presence of a hydrostatic skeleton 
A)  the presence of a mouth 
B)  the presence or absence of a complete digestive system 
C)  molting as they grow larger 
D)  presence of a hydrostatic skeleton

Question 2

Adaptations to terrestrial environments evolved independently in arthropods, mollusks, nematodes, and annelids. What logical conclusion would you make from this statement?

Accepted Answer

A)  All these groups have a coelom. 
B)  The common ancestor of all these groups was probably aquatic. 
C)  All these groups have the same type of body plan. 
D)  All these groups lost their coelom after moving to land. 
A)  All these groups have a coelom. 
B)  The common ancestor of all these groups was probably aquatic. 
C)  All these groups have the same type of body plan. 
D)  All these groups lost their coelom after moving to land.

Question 3

You find a wormlike animal while scuba diving and want to determine whether it is a nudibranch, a polychaete, or a flatworm. Finding which of the following traits would best help you classify the mystery animal?

Accepted Answer

A)  bristle-like structures on tiny appendages 
B)  a coelom 
C)  the ability to swim 
D)  bright coloration 
E)  sexual reproduction 
A)  bristle-like structures on tiny appendages 
B)  a coelom 
C)  the ability to swim 
D)  bright coloration 
E)  sexual reproduction

Question 4

Which one of these mollusk groups can be classified as suspension feeders?

Accepted Answer

A)  bivalves 
B)  gastropods 
C)  chitons 
D)  cephalopods 
A)  bivalves 
B)  gastropods 
C)  chitons 
D)  cephalopods

Question 5

Use the following information to answer the question(s) below.
Many terrestrial arthropods exchange gases with their environments by using tracheae, tubes that lead from openings (called spiracles) in the animal's exoskeleton or cuticle directly to the animal's tissues. Some arthropods can control whether their spiracles are open or closed; opening the spiracles allows carbon dioxide produced in the tissues to travel down the tracheae and be released outside the animal. Klok et al. measured the carbon dioxide emitted over time (represented by VCO2) by several species of centipedes. The figure below presents graphs of their results for two species, Cormocephalus morsitans and Scutigerina weberi. (C. J. Klok, R. D. Mercer, and S. L. Chown. 2002. Discontinuous gas-exchange in centipedes and its convergent evolution in tracheated arthropods. Journal of Experimental Biology 205:1019-29.) Copyright 2002 The Company of Biologists and the Journal of Experimental Biology.  
-Compare the graphs in the accompanying figure of carbon dioxide (CO2) emission for Cormocephalus morsitans and Scutigerina weberi. What hypothesis can you make about each centipede's habitat?

Accepted Answer

A)  C. morsitans lives in a habitat that provides more carbon dioxide than does S. weberi. 
B)  C. morsitans lives in a habitat with more predators than does S. weberi. 
C)  C. morsitans lives in a colder habitat than does S. weberi. 
D)  C. morsitans lives in a drier habitat than does S. weberi. 
A)  C. morsitans lives in a habitat that provides more carbon dioxide than does S. weberi. 
B)  C. morsitans lives in a habitat with more predators than does S. weberi. 
C)  C. morsitans lives in a colder habitat than does S. weberi. 
D)  C. morsitans lives in a drier habitat than does S. weberi.

Question 6

A student observes a wormlike organism crawling about on dead organic matter. Later, the organism sheds its outer covering. One possibility is that the organism is a larval insect (like a maggot). However, it might be a member of the phylum ________, and one way to distinguish between the two possibilities is by looking for the presence or absence of ________.

Accepted Answer

A)  Platyhelminthes; a cuticle of chitin 
B)  Nematoda; an alimentary canal 
C)  Annelida; a body cavity 
D)  Nematoda; a circulatory system 
E)  Annelida; muscle in the body wall 
A)  Platyhelminthes; a cuticle of chitin 
B)  Nematoda; an alimentary canal 
C)  Annelida; a body cavity 
D)  Nematoda; a circulatory system 
E)  Annelida; muscle in the body wall

Question 7

Which of the following organisms would you expect to have the largest surface-area-to-volume ratio? Assume that all of the following are the same total length.

Accepted Answer

A)  a rotifer 
B)  a mollusk 
C)  an annelid 
D)  an arthropod 
E)  a platyhelminth 
A)  a rotifer 
B)  a mollusk 
C)  an annelid 
D)  an arthropod 
E)  a platyhelminth

Question 8

Which mollusk clade includes members that undergo embryonic torsion?

Accepted Answer

A)  chitons 
B)  bivalves 
C)  gastropods 
D)  cephalopods 
A)  chitons 
B)  bivalves 
C)  gastropods 
D)  cephalopods

Question 9

Use the following information to answer the question(s) below.
A farm pond, usually dry during winter, has plenty of water and aquatic pond life during the summer. One summer, Sarah returns to the family farm from college. Observing the pond, she is fascinated by some six-legged organisms that can crawl about on submerged surfaces or, when disturbed, seemingly "jet" through the water. Watching further, she is able to conclude that the "mystery organisms" are ambush predators, and their prey includes everything from insects to small fish and tadpoles.
-If the pond organisms are larvae, rather than adults, Sarah should expect them to have all of the following structures, EXCEPT ________.

Accepted Answer

A)  antennae 
B)  an open circulatory system 
C)  an exoskeleton of chitin 
D)  complex eyes 
E)  sex organs 
A)  antennae 
B)  an open circulatory system 
C)  an exoskeleton of chitin 
D)  complex eyes 
E)  sex organs

Question 10

The protostome developmental sequence arose just once in evolutionary history, resulting in two main subgroups-Lophotrochozoa and Ecdysozoa. What does this finding suggest?

Accepted Answer

A)  These two subgroups have a common ancestor that was a deuterostome. 
B)  The protostomes are a polyphyletic group. 
C)  Division of these two groups occurred after the protostome developmental sequence appeared. 
D)  The lophotrochozoans are monophyletic. 
A)  These two subgroups have a common ancestor that was a deuterostome. 
B)  The protostomes are a polyphyletic group. 
C)  Division of these two groups occurred after the protostome developmental sequence appeared. 
D)  The lophotrochozoans are monophyletic.

Question 11

Use the following information to answer the question(s) below.
Many terrestrial arthropods exchange gases with their environments by using tracheae, tubes that lead from openings (called spiracles) in the animal's exoskeleton or cuticle directly to the animal's tissues. Some arthropods can control whether their spiracles are open or closed; opening the spiracles allows carbon dioxide produced in the tissues to travel down the tracheae and be released outside the animal. Klok et al. measured the carbon dioxide emitted over time (represented by VCO2) by several species of centipedes. The figure below presents graphs of their results for two species, Cormocephalus morsitans and Scutigerina weberi. (C. J. Klok, R. D. Mercer, and S. L. Chown. 2002. Discontinuous gas-exchange in centipedes and its convergent evolution in tracheated arthropods. Journal of Experimental Biology 205:1019-29.) Copyright 2002 The Company of Biologists and the Journal of Experimental Biology.  
-On which body segment are arthropod wings attached?

Accepted Answer

A)  head 
B)  abdomen 
C)  thorax 
D)  evenly split between the abdomen and thorax 
A)  head 
B)  abdomen 
C)  thorax 
D)  evenly split between the abdomen and thorax

Question 12

The possession of two pairs of antennae is a characteristic of ________.

Accepted Answer

A)  spiders 
B)  insects 
C)  centipedes 
D)  millipedes 
E)  crustaceans 
A)  spiders 
B)  insects 
C)  centipedes 
D)  millipedes 
E)  crustaceans

Question 13

All arthropods ________.
1) undergo complete metamorphosis
2) have jointed appendages
3) molt
4) have segmented bodies
5) have an exoskeleton or cuticle

Accepted Answer

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

Question 14

Nematode worms and annelid worms share which of the following features?

Accepted Answer

A)  a digestive tract with two openings (a mouth and an anus) 
B)  molting 
C)  presence of a circulatory system 
D)  presence of segmentation 
E)  absence of species with parasitic lifestyles 
A)  a digestive tract with two openings (a mouth and an anus) 
B)  molting 
C)  presence of a circulatory system 
D)  presence of segmentation 
E)  absence of species with parasitic lifestyles

Exam 31: Protostome Animals

When considering the wormlike phyla within the protostomes, which feature is most useful in distinguishing groups?

Adaptations to terrestrial environments evolved independently in arthropods, mollusks, nematodes, and annelids. What logical conclusion would you make from this statement?

You find a wormlike animal while scuba diving and want to determine whether it is a nudibranch, a polychaete, or a flatworm. Finding which of the following traits would best help you classify the mystery animal?

Which one of these mollusk groups can be classified as suspension feeders?

Which of the following organisms would you expect to have the largest surface-area-to-volume ratio? Assume that all of the following are the same total length.

Which mollusk clade includes members that undergo embryonic torsion?

The protostome developmental sequence arose just once in evolutionary history, resulting in two main subgroups-Lophotrochozoa and Ecdysozoa. What does this finding suggest?

The possession of two pairs of antennae is a characteristic of ________.

All arthropods ________. 1) undergo complete metamorphosis 2) have jointed appendages 3) molt 4) have segmented bodies 5) have an exoskeleton or cuticle

Nematode worms and annelid worms share which of the following features?

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Ecosystems and Global Ecology

Lipids, Membranes, and the First Cells

Inside the Cell

Energy and Enzymes: an Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cellcell Interactions

The Cell Cycle

Meiosis

Mendel and the Gene

Dna and the Gene: Synthesis and Repair

How Genes Work

Transcription, Rna Processing, and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

The Molecular Revolution: Biotechnology and Beyond

Genes, Development, and Evolution

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Algae and Land Plants

Fungi

An Introduction to Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Sensory Systems, Signals, and Responses

Plant Reproduction and Development

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Gas Exchange and Circulation

Animal Nervous Systems

Animal Sensory Systems

Animal Movement

Chemical Signals in Animals

Animal Reproduction and Development

The Immune System in Animals

An Introduction to Ecology

Behavioral Ecology

Population Ecology

Community Ecology

Biodiversity and Conservation Biology

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