SECTION
24.1
ARTHROPOD DIVERSITY
Study Guide
KEY CONCEPT
Arthropods are the most diverse
of all animals.
MAIN IDEA:
VOCABULARY
arthropod
exoskeleton
chitin
appendage
segmentation
Arthropod features are highly adapted.
1. What are the three main features of an arthropod’s body?
CHAPTER 24
A Closer Look at Arthropods
2. What is chitin?
3. Why are jointed appendages considered an important adaptation during the evolution
of arthropods?
4. Complete the following chart with a description of and example animal for each group
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of arthropods.
Group
Description
Example
trilobites
crustaceans
chelicerates
insects
myriapods
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McDougal Littell Biology
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STUDY GUIDE, CONTINUED
MAIN IDEA:
Arthropod exoskeletons serve a variety of functions.
5. What three important body functions are made difficult by the presence of an
exoskeleton?
6. Why must an arthropod molt?
CHAPTER 24
A Closer Look at Arthropods
7. List the three steps of the molting process.
8. How is an arthropod’s circulatory system different from a vertebrate’s circulatory
system?
9. What body parts allow an arthropod to sense its surrounding environment?
MAIN IDEA:
Arthropod diversity evolved over millions of years.
11. What two species do scientists think are the closest relatives to arthropods?
Vocabulary Check
12. The word appendage comes from the Latin word appendere, which means “to hang
upon.” How does this meaning relate to the definition of appendage?
13. What word within segmentation helps you remember it as something made of separate
parts?
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10. How is an arthropod’s eye different from a mammal’s eye?
SECTION
24.2
CRUSTACEANS
Study Guide
KEY CONCEPT
Crustaceans are a diverse group
of ancient arthropods.
MAIN IDEA:
VOCABULARY
crustacean
cephalothorax
abdomen
carapace
mandible
Crustaceans evolved as marine arthropods.
1. What are the four main features of a crustacean’s body?
CHAPTER 24
A Closer Look at Arthropods
Choose a word from the box below that best fits each of the following descriptions.
abdomen
carapace
cephalothorax
2. This body section is the region of an organism in which the head
and trunk region are combined into one long section.
3. This body section refers to the rear portion of the organism.
4. This shieldlike section of cuticle covers the sides of the body and
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protects the gills.
MAIN IDEA:
Crustacean appendages can take many forms.
5. List three functions of a crustacean claw.
6. What is the function of a crustacean’s antennae?
7. What are mandibles?
8. What two body parts are used by a crustacean to move?
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McDougal Littell Biology
Study Guide
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STUDY GUIDE, CONTINUED
MAIN IDEA:
There are many different types of crustaceans.
10. Complete the following chart with a description of each crustacean group.
Group
Description
decapod
barnacle
isopod
tongue worm
11. What evidence helped to determine that barnacles and tongue worms are crustaceans?
Vocabulary Check
12. The word mandible comes from the Latin word mandere, which means “to chew.” How
does this meaning relate to the definition of mandibles?
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Study Guide
Unit 8 Resource Book
McDougal Littell Biology
Copyright by McDougal Littell, a division of Houghton Mifflin Company
CHAPTER 24
A Closer Look at Arthropods
9. In the space below, draw a simple sketch of a crustacean and label its parts.
SECTION
24.3
ARACHNIDS
Study Guide
KEY CONCEPT
Arachnids include spiders and their
relatives.
MAIN IDEA:
VOCABULARY
chelicerate
arachnid
book lung
spiracle
trachea
Arachnids are the largest group of chelicerates.
1. What is a chelicerate?
CHAPTER 24
A Closer Look at Arthropods
2. What are three characteristics of arachnids?
Choose a word from the word box below that best fits each of the following descriptions.
book lungs
Malpighian tubules
spiracles
tracheae
3. tiny holes on the abdomen that open and close to allow oxygen
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to enter
4. structures built of many thin, hollow sheets of tissue
5. tubes that carry oxygen directly to the arachnid’s tissues
6. excretory structures that allow spiders to minimize loss of water
while excreting metabolic wastes
7. In the space below, draw a simple picture of a spider and label its parts.
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McDougal Littell Biology
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STUDY GUIDE, CONTINUED
MAIN IDEA:
Arachnids have evolved into a diverse group.
8. Where is silk produced in a spider’s body?
9. List four uses of a spider’s silk.
11. List one positive and one negative aspect of an arachnid’s role as a predator.
Vocabulary Check
12. The word spiracle comes from the Latin word spirare, which means “to breathe.”
Explain how this meaning relates to the definition of a spiracle.
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CHAPTER 24
A Closer Look at Arthropods
10. What is the function of a spider’s venom?
Be Creative
13. Draw a cartoon that illustrates the importance of spiders as predators.
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Study Guide
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SECTION
24.4
INSECT ADAPTATIONS
Study Guide
KEY CONCEPT
Insects show an amazing range of adaptations.
MAIN IDEA:
VOCABULARY
incomplete metamorphosis
complete metamorphosis
pupa
Insects are the dominant terrestrial arthropods.
1. Explain why insects are considered an incredible success story.
CHAPTER 24
A Closer Look at Arthropods
2. Draw a picture of an insect and label the following parts: head, thorax, abdomen, legs,
Copyright by McDougal Littell, a division of Houghton Mifflin Company
wings, antennae, and compound eyes.
MAIN IDEA:
Insects undergo metamorphosis.
3. Describe incomplete metamorphosis.
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McDougal Littell Biology
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STUDY GUIDE, CONTINUED
4. Complete the following process diagram with details about the complete metamorphosis
CHAPTER 24
A Closer Look at Arthropods
of a butterfly.
Egg
Larva
Adult
Pupa
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MAIN IDEA: Insects have adapted to life on land.
For each type of insect, indicate whether it uses a proboscis or mandibles to eat.
5. butterfly
6. ant
7. beetle
8. moth
Vocabulary Check
9. What happens during a metamorphosis?
10. What is the difference between complete and incomplete metamorphosis?
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Study Guide
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SECTION
24.5
ARTHROPODS AND HUMANS
Study Guide
KEY CONCEPT
Arthropods and humans interact in many ways.
MAIN IDEA:
VOCABULARY
insecticide
vector
Arthropods and humans share many of the same resources.
1. In what way do arthropods compete with humans for resources?
CHAPTER 24
A Closer Look at Arthropods
2. What is an insecticide?
3. What are three negative aspects of insecticide use?
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4. List and describe three safer methods scientists have developed to control insects.
MAIN IDEA:
Some arthropods can spread human diseases.
5. What is a vector?
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McDougal Littell Biology
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STUDY GUIDE, CONTINUED
6. Complete the following chart with details about the following diseases transmitted to
humans by arthropods.
Disease
Vector
Description
bubonic plague
yellow fever
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A Closer Look at Arthropods
malaria
West Nile virus
Vocabulary Check
7. The suffix -cide comes from the Latin word caedere, which means “to strike, kill.” How
does this meaning relate to the meaning of the word insecticide?
8. Vector comes from the Latin word vectus, which means “to carry.” Explain how this
Be Creative
9. Draw a cartoon that illustrates the world through an insect’s eyes. How might an insect
see the world differently than you do?
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Study Guide
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McDougal Littell Biology
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meaning relates to the definition of a vector.