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Table of Contents pages iv-v
Unit 1 What is Biology? Unit 2 Ecology Unit
3 The Life of a Cell Unit 4 Genetics Unit 5
Change Through Time Unit 6 Viruses, Bacteria,
Protists, and Fungi Unit 7 Plants Unit 8
Invertebrates Unit 9 Vertebrates Unit 10 The
Human Body
3
Table of Contents pages iv-v
Unit 1 What is Biology? Chapter 1
Biology The Study of Life Unit 2 Ecology
Chapter 2 Principles of Ecology Chapter
3 Communities and Biomes Chapter 4
Population Biology Chapter 5 Biological
Diversity and Conservation Unit 3 The Life of a
Cell Chapter 6 The Chemistry of Life
Chapter 7 A View of the Cell Chapter 8
Cellular Transport and the Cell Cycle
Chapter 9 Energy in a Cell
4
Table of Contents pages iv-v
Unit 4 Genetics Chapter 10 Mendel and
Meiosis Chapter 11 DNA and Genes
Chapter 12 Patterns of Heredity and Human
Genetics Chapter 13 Genetic Technology Unit
5 Change Through Time Chapter 14 The
History of Life Chapter 15 The Theory of
Evolution Chapter 16 Primate Evolution
Chapter 17 Organizing Lifes Diversity
5
Table of Contents pages iv-v
Unit 6 Viruses, Bacteria, Protists, and Fungi
Chapter 18 Viruses and Bacteria Chapter
19 Protists Chapter 20 Fungi Unit 7
Plants Chapter 21 What Is a Plant?
Chapter 22 The Diversity of Plants
Chapter 23 Plant Structure and Function
Chapter 24 Reproduction in Plants
6
Table of Contents pages iv-v
Unit 8 Invertebrates Chapter 25 What Is
an Animal? Chapter 26 Sponges,
Cnidarians, Flatworms, and
Roundworms Chapter 27
Mollusks and Segmented Worms Chapter 28
Arthropods Chapter 29 Echinoderms and
Invertebrate
Chordates
7
Table of Contents pages iv-v
Unit 9 Vertebrates Chapter 30 Fishes
and Amphibians Chapter 31 Reptiles and
Birds Chapter 32 Mammals Chapter 33
Animal Behavior Unit 10 The Human Body
Chapter 34 Protection, Support, and
Locomotion Chapter 35 The Digestive and
Endocrine Systems Chapter 36 The Nervous
System Chapter 37 Respiration,
Circulation, and Excretion Chapter 38
Reproduction and Development Chapter 39
Immunity from Disease
8
Unit Overview pages 670-671
Invertebrates
What Is an animal?
Sponges, Cnidarians, Flatworms, and Roundworms
Mollusks and Segmented Worms
Arthropods
Echinoderms and Invertebrate Chordates
9
Chapter Contents page
Chapter 27 Introduction Mollusks an Segmented
Worms 27.1 Mollusks 27.1 Section
Check 27.2 Segmented Worms 27.2 Section
Check Chapter 27 Summary Chapter 27 Assessment
10
Chapter Intro-page 720
What Youll Learn
You will distinguish among the classes of
mollusks and segmented worms.
You will compare and contrast the adaptations of
mollusks and segmented worms.
11
27.1 Section Objectives page 721
Section Objectives

• Identify the characteristics of mollusks.

• Compare the adaptations of gastropod, bivalve,
  and cephalopod mollusks in their biomes.

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Section 27.1 Summary pages 721-727
What is a mollusk?

• Slugs, snails, squids, and some animals that live
  in shells in the ocean or on the beach are all
  mollusks. These organisms belong to the phylum
  Mollusca.

• Although most species live in the ocean, others
  live in freshwater and moist terrestrial habitats.

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Section 27.1 Summary pages 721-727
What is a mollusk?

• Some mollusks have shells, and others, including
  slugs and squids, are adapted to life without a
  hard covering.

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Section 27.1 Summary pages 721-727
What is a mollusk?

• All mollusks have bilateral symmetry, a coelom, a
  digestive tract with two openings, a muscular
  foot, and a mantle.

Arm
Reduced internal shell
Head
Mantle
Tentacle
Gut
Squid
Visceral mass
Shell
Mantle
Foot
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Section 27.1 Summary pages 721-727
What is a mollusk?

• The mantle (MAN tuhl) is a membrane that
  surrounds the internal organs of the mollusk. In
  shelled mollusks, the mantle secretes the shell.

Mantle
Snail
Shell
Gut
Head
Foot
Shell
Visceral mass
Foot
Mantle
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Section 27.1 Summary pages 721-727
How mollusks obtain food

• Snails, like many mollusks, use a rasping
  structure called a radula to obtain food.

Radula

• A radula (RA juh luh), located within the mouth
  of a mollusk, is a tonguelike organ with rows of
  teeth. The radula is used to drill, scrape,
  grate, or cut food.

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Section 27.1 Summary pages 721-727
How mollusks obtain food

• Octopuses and squids are predators that use their
  radulas to tear up the food that they capture
  with their tentacles.

• Other mollusks are grazers and some are filter
  feeders.

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Section 27.1 Summary pages 721-727
How mollusks obtain food

• Bivalves do not have radulas they filter food
  from the water.

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Section 27.1 Summary pages 721-727
Reproduction in mollusks

• Mollusks reproduce sexually and most have
  separate sexes.

• In most aquatic species, eggs and sperm are
  released at the same time into the water, where
  external fertilization takes place.

• Many gastropods that live on land, and a few
  bivalves, are hermaphrodites and produce both
  eggs and sperm. Fertilization is internal.

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Section 27.1 Summary pages 721-727
Reproduction in mollusks

• Some marine mollusks have free swimming larvae
  that propel themselves.

• Most marine snails and bivalves have another
  developmental stage called a veliger in which he
  beginnings of a foot, shell, and mantle can be
  seen.

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Section 27.1 Summary pages 721-727
Nervous control in mollusks

• Molusks have simple nervous systems that
  coordinate their movement and behavior.

• Some more advanced mollusks have a brain.

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Section 27.1 Summary pages 721-727
Nervous control in mollusks

• Most mollusks have paired eyes that range from
  simple cups that detect light to the complex eyes
  of octopuses that have irises, pupils, and
  retinas similar to the eyes of humans.

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Section 27.1 Summary pages 721-727
Circulation in mollusks

• Mollusks have a well-developed circulatory system
  that includes a three-chambered heart.

Heart
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Section 27.1 Summary pages 721-727
Circulation in mollusks

• In most mollusks, the heart pumps blood through
  an open circulatory system.

• In an open circulatory system, the blood moves
  through vessels and into open spaces around the
  body organs.

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Section 27.1 Summary pages 721-727
Circulation in mollusks

• Some mollusks, such as octopuses, move nutrients
  and oxygen through a closed circulatory system.

• In a closed circulatory system, blood moves
  through the body enclosed entirely in a series of
  blood vessels.

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Section 27.1 Summary pages 721-727
Respiration in mollusks

• Most mollusks have respiratory structures called
  gills.

• Gills are specialized parts of the mantle that
  consist of a system of filamentous projections
  that contain a rich supply of blood for the
  transport for gases.

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Section 27.1 Summary pages 721-727
Excretion in mollusks

• Mollusks are the oldest known animals to have
  evolved excretory structures called nephridia.

• Nephridia (nih FRIH dee uh) are organs that
  remove metabolic wastes from an animals body.

• Mollusks have one or two nephridia that collect
  wastes from the coelom, which is located around
  the heart only.

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Section 27.1 Summary pages 721-727
Excretion in mollusks

• Wastes are discharged into the mantle cavity, and
  expelled from the body by the pumping of the
  gills.

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Section 27.1 Summary pages 721-727
Diversity of Mollusks

• Phylum Mollusca is large and diverse.

• Three mollusk classesGastropoda, Bivalvia, and
  Cephalopodainclude the most common and well-
  known species.

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Section 27.1 Summary pages 721-727
Gastropods One-shelled mollusks

• The largest class of mollusks is Gastropoda, or
  the stomach-footed mollusks.

• The name comes from the way the animals large
  foot is positioned under the rest of its body.

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Section 27.1 Summary pages 721-727
Gastropods One-shelled mollusks

• Shelled gastropods include snails, abalones,
  conches, periwinkles, whelks, limpets, cowries,
  and cones.

• Instead of being protected by a shell, the body
  of a slug is protected by a thick layer of mucus.

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Section 27.1 Summary pages 721-727
Gastropods One-shelled mollusks

• Colorful sea slugs, also called nudibranchs, are
  protected in another way.

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Section 27.1 Summary pages 721-727
Gastropods One-shelled mollusks

• When certain species of sea slugs feed on
  jellyfishes, they incorporate the poisonous
  nematocysts of the jellyfish into their own
  tissues without causing these cells to discharge.

• Any fishes trying to eat the sea slugs are
  repelled when the nematocysts discharge into the
  unlucky predator.

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Section 27.1 Summary pages 721-727
Bivalves Two-shelled mollusks

• Two-shelled mollusks such as clams, oysters, and
  scallops belong to the class Bivalvia.

• Most bivalves are marine, but a few species live
  in freshwater habitats.

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Section 27.1 Summary pages 721-727
Bivalves Two-shelled mollusks

• Bivalves have no distinct head or radula. Most
  use their large, muscular foot for burrowing in
  the mud or sand at the bottom of the ocean or a
  lake.

• A ligament, like a hinge, connects their two
  shells, called valves strong muscles allow the
  valves to open and close over the soft body.

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Section 27.1 Summary pages 721-727
Bivalves Two-shelled mollusks

• One of the main differences between gastropods
  and bivalves is that bivalves are filter feeders
  that obtain food by filtering small particles
  from the surrounding water.

• Gill cilia beat to draw water in through an
  incurrent siphon.

• As water moves over the gills, food and sediments
  become trapped in mucus.

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Section 27.1 Summary pages 721-727
Bivalves Two-shelled mollusks

• Cilia that line the gills push food particles to
  the mouth.

• Large particles, sediment, and anything else that
  is rejected is transported to the mantle where it
  is expelled through the excurrent siphon, or to
  the foot, where it is eliminated from the
  animals body.

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Section 27.1 Summary pages 721-727
Cephalopods Head-footed mollusks

• This class includes the octopus, squid,
  cuttlefish, and chambered nautilus.

• The only cephalopod with a shell is the chambered
  nautilus, but some species, such as the
  cuttlefish, have a reduced internal shell.

39
Section 27.1 Summary pages 721-727
Cephalopods Head-footed mollusks

• In cephalopods, the foot has evolved into
  tentacles with suckers, hooks, or adhesive
  structures.

• Cephalopods swim or walk over the ocean floor in
  pursuit of their prey, capturing it with their
  tentacles.

40
Section 27.1 Summary pages 721-727
Cephalopods Head-footed mollusks

• Once tentacles have captured prey, it is brought
  to the mouth and bitten with beaklike jaws.

• Then the food is torn and pulled into the mouth
  by the radula.

41
Section 27.1 Summary pages 721-727
Cephalopods Head-footed mollusks

• Cephalopods have siphons that expel water.

• These mollusks can expel water forcefully in any
  direction, and move quickly by jet propulsion.
  Squids can attain speed of 20m per second using
  this system of movement.

Direction of squid
Water in
Water out
42
Section 27.1 Summary pages 721-727
Cephalopods Head-footed mollusks

• Squids and octopuses also can release a dark
  fluid to cloud the water.

• This ink helps to confuse their predators so
  they can make a quick escape.

43
Section 1 Check
Question 1
Which of the following mollusks does NOT
have a radula, and why?
A. octopus
B. sea snail
C. clam
D. slug
The answer is C. Clams are filter feeders that
do not need a radula to obtain food.
CA Biology/Life Sciences 9a
44
Section 1 Check
Question 2
Which of the following is NOT a function of
the tentacles of a land snail?
A. smelling
B. feeling
C. moving the eyes
D. capturing prey
The answer is D, capturing prey.
45
Section 1 Check
Question 3
Which are the first mollusks you would
expect to be affected by pollution and why?
A. clams
B. snails
C. octopuses
D. squid
CA Biology/Life Sciences 9a
46
Section 1 Check
The answer is A. Clams are filter feeders. They
would be most likely to ingest plankton and
become polluted. Later, other mollusks like sea
snails that prey on clams might ingest the same
pollutant when they eat the clams.
CA Biology/Life Sciences 9a
47
Section 1 Check
Question 4
Nephridia are organs used for _____.
A. circulation
B. respiration
C. movement
D. excretion
The answer is D, excretion.
CA Biology/Life Sciences 9a
48
27.2 Section Objectives page 728
Section Objectives

• Describe the characteristics of segmented worms
  and their importance to the survival of these
  organisms.

• Compare and contrast the classes of segmented
  worms.

49
Section 27.2 Summary pages 728-733
What is a segmented worm?

• Segmented worms are classified in the phylum
  Annelida. They include leeches and bristleworms
  as well as earthworms.

• Segmented worms are bilaterally symetrical and
  have a coelom and two body openings.

50
Section 27.2 Summary pages 728-733
What is a segmented worm?

• The basic body plan of segmented worms is a tube
  within a tube.

• The internal tube, suspended within the coelom,
  is the digestive tract.

51
Section 27.2 Summary pages 728-733
What is a segmented worm?

• Food is taken in by the mouth, an opening in the
  anterior end of the worm, and wastes are released
  through the anus, an opening at the posterior end.

52
Section 27.2 Summary pages 728-733
What is a segmented worm?

• Most segmented worms have tiny bristles called
  setae (SEE tee) on each segment.

• The setae help segmented worms move by providing
  a way to anchor their bodies in the soil so each
  segment can move the animal along.

Setae
53
Section 27.2 Summary pages 728-733
Segmentation supports diversified functions

• The most distinguishing characteristic of
  segmented worms is their cylindrical bodies that
  are divided into ringed segments.

• In most species, this segmentation continues
  internally as each segment is separated from the
  others by a body partition.

54
Section 27.2 Summary pages 728-733
Segmentation supports diversified functions

• Each segment has its own muscles, allowing
  shortening and lengthening of the body.

• Segmentation also allows for specialization of
  body tissues.

• Certain segments have modifications for functions
  such as sensing and reproduction.

55
Section 27.2 Summary pages 728-733
Nervous system

• Segmented worms have simple nervous systems in
  which organs in anterior segments have become
  modified for sensing the environment.

• Some sensory organs are sensitive to light, and
  eyes with lenses and retinas have evolved in
  certain species.

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Section 27.2 Summary pages 728-733
Nervous system

• In some species there is a brain located in an
  anterior segment.

Setae

• Nerve cords connect the brain to nerve centers
  called ganglia, located in each segment.

Gizzard
Aortic arches
Brain
Nerve
Esophagus
Intestine
Crop
Mouth
57
Section 27.2 Summary pages 728-733
Circulation and respiration

• Segmented worms have a closed circulatory system.

• Blood carrying oxygen to and carbon dioxide from
  body cells flow through vessels to reach all
  parts of the body.

• Segmented worms must live in water or in wet
  areas on land because they also exchange gases
  directly through their moist skin.

58
Section 27.2 Summary pages 728-733
Digestion and excretion

• Segmented worms have a complete internal
  digestive tract that runs the length of the body.

• Food and soil taken in by the mouth eventually
  pass to the gizzard.

59
Section 27.2 Summary pages 728-733
Digestion and excretion
Gizzard
Crop
Mouth

• In the gizzard, a muscular sac and hard particles
  help grind soil and food before they pass into
  the intestine.

60
Section 27.2 Summary pages 728-733
Digestion and excretion

• Undigested material and solid wastes pass out the
  worms body through the anus.

• Segmented worms have two nephridia in almost
  every segment that collect waste products and
  transport them through the coelom and out of the
  body.

Nephridia
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Section 27.2 Summary pages 728-733
Reproduction in segmented worms

• Earthworms and leeches are hermaphrodites,
  producing both eggs and sperm.

• During mating, two worms exchange sperm.

• Each worm forms a capsule for the eggs and sperm.

62
Section 27.2 Summary pages 728-733
Reproduction in segmented worms

• The eggs are fertilized in the capsule, then the
  capsule slips off the worm and is left behind in
  the soil.

• In two to three weeks, young worms emerge from
  the eggs.

63
Section 27.2 Summary pages 728-733
Reproduction in segmented worms

• Bristleworms and their relatives have separate
  sexes and reproduce sexually.

64
Section 27.2 Summary pages 728-733
Reproduction in segmented worms

• Usually eggs and sperm are released into the
  seawater, where fertilization takes place.

• Bristleworm larvae hatch in the sea and become
  part of the plankton.

• Once segment development begins, the worm settles
  to the bottom.

65
Section 27.2 Summary pages 728-733
Diversity of Segmented Worms

• The phylum Annelida includes three classes
  class Oligochaeta, earthworms class Polychaeta,
  bristleworms and their relatives and class
  Hirudinea, leeches.

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Section 27.2 Summary pages 728-733
Earthworms

• Earthworms are the most well-known annelids
  because they can be seen easily by most people.

• As an earthworm burrows through soil, it loosens,
  aerates, and fertilizes the soil.

67
Section 27.2 Summary pages 728-733
Gizzard
Mouth
Crop
Setae
Circulatory system
Nephridia
Nervous system
Earthworms
68
Section 27.2 Summary pages 728-733
Bristleworms and their relatives

• The class Polychaeta includes bristleworms and
  their relativesfanworms, lug worms, plumed
  worms, and sea mice.

69
Section 27.2 Summary pages 728-733
Bristleworms and their relatives

• Most body segements of a polychaete have many
  setae, hence the name. Polychaete means many
  bristles.

• Most body segments of a polychaete also have a
  pair of appendages called parapodia, which can be
  used for swimming or crawling over corals and the
  bottom of the sea.

70
Section 27.2 Summary pages 728-733
Bristleworms and their relatives

• Parapodia also function in gas exchange.

• A polychaete has a head with well-developed sense
  organs, including eyes.

71
Section 27.2 Summary pages 728-733
Leeches

• Leeches are segmented worms with flattened bodies
  and usually no setae.

• Unlike earthworms, many species are parasites
  that suck blood or other body fluids from the
  bodies of their hosts, which include ducks,
  turtles, fishes, and humans.

72
Section 27.2 Summary pages 728-733
Leeches

• Front and rear suckers enable leeches to attach
  themselves to their hosts.

73
Section 27.2 Summary pages 728-733
Leeches

• The saliva of the leech contains chemicals that
  act as an anesthetic.

• Other chemicals prevent the blood from clotting.

• A leech can ingest two to five times its own
  weight in one meal.

74
Section 27.2 Summary pages 728-733
Origins of Mollusks and Segmented Worms

• Fossil records show that mollusks lived in great
  numbers as long as 500 million years ago.

• Gastropod, bivalve, and cephalopod fossils have
  been found in Precambrian deposits.

75
Section 27.2 Summary pages 728-733
Origins of Mollusks and Segmented Worms

• Annelids probably evolved in the sea, perhaps
  from larvae of ancestral flatworms.

76
Section 27.2 Summary pages 728-733
Origins of Mollusks and Segmented Worms

• Tubes constructed by polychaetes are the most
  common fossils of this phylum.

• Some of these tubes appear in the fossil record
  as early as 540 million years ago.

77
Section 2 Check
Question 1
Why must segmented worms live in a moist
environment?
Answer
Segmented worms must live in or near water
because they exchange gases directly through
their moist skin.
CA Biology/Life Sciences 9a
78
Section 2 Check
Question 2
During mating, earthworms exchange _____.
A. eggs
B. sperm
C. capsules containing both sperm and eggs
D. larvae
The answer is B, sperm.
79
Section 2 Check
Question 3
1
Using this figure, give the reason why you
would determine this to be the anterior end of
the organism?
2
3
Brain
4
Pharynx
5
6
Esophagus
7
8
Blood vessel
9
10
11
Crop
12
Nephridia
13
14
15
16
80
Section 2 Check
The anterior portion of an organism would
logically include the brain, as well as the
initial parts of a gut, like the esophagus and
crop (the esophagus and crop are necessary to the
initial phases of digestion).
1
2
3
Brain
4
Pharynx
5
6
Esophagus
7
8
Blood vessel
9
10
11
Crop
12
13
14
15
16
81
Section 2 Check
Question 4
Which organism would likely get the most use
from a gizzard, an earthworm or a leech?
Answer
A gizzard grinds organic matter into small pieces
so the nutrients in the food can be absorbed.
Since a leechs food is liquid (blood), the
earthworm would use a gizzard the most, to grind
the food and soil it ingests.
CA Biology/Life Sciences 9a
82
Section 2 Check
Question 5
Earthworms are considered to be ______.
A. predators
B. parasites
C. filter feeders
D. grazers
The answer is D, grazers.
CA Biology/Life Sciences 9a
83
Chapter Summary 27.1
Mollusks

• Mollusks have bilateral symmetry, a coelom, and a
  digestive tract with two openings. Many also
  have shells.

• Most gastropods, such as snails, have a shell,
  mantle, radula, an open circulatory system,
  gills, and nephridia. Gastropods without shells,
  such as slugs, are protected by a covering of
  mucus.

84
Chapter Summary 27.1
Mollusks

• Bivalve mollusks have paired shells, called
  valves, and are filter feeders. They have no
  radula. Clams and scallops are bivalves.

• Cephalopods have tentacles with suckers, beaklike
  jaws, a mouth with a radula, and a closed
  circulatory system. Cephalopods include the
  octopus, squid, and chambered nautilus.

85
Chapter Summary 27.2
Segmented Worms

• The phylum Annelida includes the earthworms,
  bristleworms, and their relatives, and leeches.
  Annelida are bilaterally symmetrical and have a
  coelom and two body openings some have larvae
  that look like the larvae of mollusks. Their
  bodies are cylindrical and segmented.

• Earthworms have complex digestive, excretory,
  muscular, and circulatory systems.

86
Chapter Summary 27.2
Segmented Worms

• Bristleworms and their relatives are mostly
  marine species. They have many setae and
  parapodia that are used for crawling along.

• Leeches are flattened, segmented worms. Most are
  aquatic parasites.

• Fossil remains of mollusks show that they first
  lived over 500 million years ago. Fossil records
  show that segmented worms first appeared 540
  million years ago.

87
Chapter Assessment
Question 1
With the exception of slugs, all mollusks that
are slow-moving or sessile have shells. Why?
CA Biology/Life Sciences 6g
88
Chapter Assessment
Shells provide organisms with a place to hide
that is always near them, since they cannot
quickly escape a predator.
CA Biology/Life Sciences 6g
89
Chapter Assessment
Question 2
Why is a closed circulatory system more efficient
than an open circulatory system?
CA Biology/Life Sciences 6g
90
Chapter Assessment
A closed circulatory system is more efficient
because blood is transported entirely in closed
vessels that can reach deep into the organisms
tissues and provide efficient gas exchange. In
an open circulatory system, tissues farthest from
the open spaces containing blood are not so
likely to be reached for efficient gas exchange.
CA Biology/Life Sciences 6g
91
Chapter Assessment
Question 3
Why do scientists consider cephalopods to be the
most recently evolved of all mollusks?
Answer
Cephalopods possess the most complex structures
of all mollusks, such as complex eyes, complex
brains, closed circulatory systems and feet that
have evolved into complex structures like arms
and tentacles.
CA Biology/Life Sciences 6g
92
Chapter Assessment
Question 4
Why are mollusks considered to be excellent index
fossils?
Answer
Mollusks are generally well preserved in the
fossil record, abundant, easy to recognize, and
widely distributed geographically.
CA Biology/Life Sciences 8e
93
Chapter Assessment
Question 5
Which of the following is NOT a food source for
humans and why?
A. abalones
B. octopuses
C. ammonites
D. conches
The answer is C. Ammonites are not a food source
for any organism, because they are extinct.
CA Biology/Life Sciences 8e
94
Chapter Assessment
Question 6
How does a leech benefit from the chemicals in
its saliva that prevent clots from forming?
Answer
Preventing blood clots keeps a free flow of blood
available to the leech until it is done feeding.
95
Chapter Assessment
Question 7
What is the function of parapodia?
Answer
Polychaetes use parapodia for swimming, crawling,
and for gas exchange.
CA Biology/Life Sciences 9a
96
Chapter Assessment
Question 8
Why do annelids have such a limited fossil record?
Answer
The fossil record for segmented worms is limited
because segmented worms have almost no hard body
parts from which fossils could develop.
CA Biology/Life Sciences 8e
97
Chapter Assessment
Question 9
What is the function of setae?
Answer
Setae help segmented worms move by providing a
way to anchor their bodies in the soil so each
segment can move the animal along.
98
Chapter Assessment
Question 10
Which of the following features do annelids NOT
share with mollusks?
A. coelom
B. bilateral symmetry
C. digestive tract with two openings
D. segmented bodies
The answer is D, segmented bodies.
99
Photo Credits
Photo Credits

• General Biololgical Inc.  
• Digital Stock  
• Joey Jacques
• Corbis   
• PhotoDisc
• Alton Biggs

100
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End of Chapter 27 Show