Download Introduction to Animals

Chapter 24 Introduction to Animals
Section 1: Animal Characteristics
Section 2: Animal Body Plans
Section 3: Sponges and Cnidarians
Click on a lesson name to select.
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
General Animal Features
 The ancestral animals at the beginning of
the evolutionary tree are eukaryotic and
multicellular.
 They developed adaptations in structure
that enabled them to function in numerous
habitats.
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Feeding and Digestion
 Animals are heterotrophic.
 The structure or form of an animal’s mouth
parts determines how its mouth functions.
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Support
 Invertebrates
 Exoskeletons
 Hard or tough outer coverings that provide
a framework of support
 Protect soft body tissues
 Provide protection from predators
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Support
 Vertebrates
 Endoskeletons
 Protect internal organs
 Provide support for the body
 Provide an internal brace for muscles to
pull against
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Movement
 The evolution of nerve and muscle tissues
enables animals to move in ways that are
more complex and faster than organisms
in other kingdoms.
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Reproduction
 Fertilization occurs when the sperm penetrates
the egg to form a fertilized egg cell called the
zygote.
 Internal fertilization
 External fertilization
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
 Asexual reproduction means that a single
parent produces offspring that are genetically
identical to itself.
 Budding
 Fragmentation
 Regeneration
 Parthenogenesis
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Early Development
 The zygote undergoes mitosis and a series
of cell divisions to form new cells.
 The cells continue to divide, forming a fluidfilled ball of cells called the blastula.
 The blastula continues to undergo cell
division as some cells move inward to form
a gastrula.
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Tissue Development
 Endoderm
 inner layer of cells in the gastrula
 Ectoderm
 outer layer of cells in the gastrula
 Mesoderm
 layer of cells between the endoderm
and ectoderm
Chapter 24 Introduction to Animals
24.1 Animal Characteristics
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Evolution of Animal Body Plans
 Anatomical features in animals’ body
plans mark the branching points on the
evolutionary tree.
 Relationships on this tree are inferred by
studying similarities in embryological
development and shared anatomical features.
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Symmetry
 Similarity or balance among body structures of organisms
 Asymmetry
 Radial symmetry
 Bilateral symmetry
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Cephalization
 The tendency to concentrate nervous tissue
and sensory organs at the anterior end of
the animal
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Body Cavities
 Coelomates
 Have a fluidfilled cavity with
tissue formed
from mesoderm
that lines and encloses the organs in the
coelom
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Body Cavities
 Pseudocoelomates
 Have a fluid-filled
body cavity that
develops between
the mesoderm and
the endoderm rather than developing
entirely within the mesoderm
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Body Cavities
 Acoelomates
 Have solid bodies
without a fluid-filled
body cavity
between the gut
and the body wall
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Development in Coelomate Animals
 Protostomes
 The mouth develops from the first opening in
the gastrula.
 Deuterostomes
 The anus develops from the first opening in
the gastrula.
Chapter 24 Introduction to Animals
24.2 Animal Body Plans
Segmentation
 Segmented animals can be “put together”
from a succession of similar parts.
 Can survive damage to one segment
 Movement is more effective
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Sponges
 Sponges do not develop tissues.
 Collar cells with flagella line the inside of
the sponge and whip back and forth
drawing water into the body of the sponge.
 Water and waste materials are expelled
from the sponge through the osculum.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Filter Feeder
 Food particles cling to the cells.
 Digestion of nutrients takes place within
each cell.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Archaeocytes
 Specialized cells that secrete spicules, which
are the support structures of sponges
 Spicules are small, needlelike structures
made of calcium carbonate, silica, or a tough
fibrous protein called spongin
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Sponge Diversity
 Demospongiae
 Calcarea
 Hexactinellida
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Reproduction
 Reproduce asexually
 Fragmentation
 Budding
 Gemmules
 Reproduce sexually
 Eggs remain within a sponge.
 Sperm are released into the water.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Cnidarians
 Have one body opening and two layers
of cells
 Outer layer functions in protecting the
internal body
 Inner layer functions mainly in digestion
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Feeding and Digestion
 Tentacles are armed with stinging cells called
cnidocytes.
 A nematocyst is a capsule that holds a coiled
tube containing poison and barbs.
 Water inside an undischarged nematocyst
is under an osmotic pressure of more than
150 atmospheres.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
 As the osmotic
pressure increases,
the nematocyst
discharges forcefully.
 A barb is capable
of penetrating a
crab shell.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
 Cells lining the
gastrovascular cavity
release digestive
enzymes over
captured prey.
 Undigested materials
are ejected though
the mouth.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Response to Stimuli
 A nerve net conducts impulses to and
from all parts of the body.
 The impulses cause contractions of
musclelike cells in the two cell layers.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Reproduction
 Two body forms
 Polyp
 Medusa
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
 The two body forms
of cnidarians can be
observed in the life
cycle of jellyfishes.
Chapter 24 Introduction to Animals
24.3 Sponges and Cnidarians
Cnidarian Diversity
 Hydroids
 Jellyfishes
 Sea anemones and corals
Chapter 24 Introduction to Animals
Chapter 24 Introduction to Animals
Chapter Resource Menu
Chapter Diagnostic Questions
Formative Test Questions
Chapter Assessment Questions
Standardized Test Practice
biologygmh.com
Glencoe Biology Transparencies
Image Bank
Vocabulary
Animation
Click on a hyperlink to view the corresponding feature.
Chapter 24 Introduction to Animals
Chapter Diagnostic
Questions
Which animal is not an invertebrate?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. lobster
B. shark
C. cicada
D. earthworm
Chapter 24 Introduction to Animals
Chapter Diagnostic
Questions
What is the tough outer covering of most
invertebrates called?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. exoskeleton
B. endoskeleton
C. endoderm
D. mesoderm
Chapter 24 Introduction to Animals
Chapter Diagnostic
Questions
Which statement is not true of animals?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. Animal cells have
cell walls.
B. Animals are
heterotrophic.
C. Animals probably
evolved from
early protists.
D. Animal cells
become tissues.
Chapter 24 Introduction to Animals
24.1 Formative
Questions
From which organisms might animals have
evolved?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. animal-like bacteria
B. autotrophic invertebrates
C. colonial protists
D. multicellular fungi
Chapter 24 Introduction to Animals
24.1 Formative
Questions
What is a group of cells that performs a
specific function?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. organ
B. tissue
C. gastrula
D. mesoderm
Chapter 24 Introduction to Animals
24.1 Formative
Questions
What is one of the most unique
characteristics of the animal kingdom?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. advanced cell structure
B. complex movement
C. sexual reproduction
D. organ development
Chapter 24 Introduction to Animals
24.1 Formative
Questions
What is the term for an individual animal that
produces both eggs and sperm?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. acoelomate
B. hermaphrodite
C. heterosexual
D. invertebrate
Chapter 24 Introduction to Animals
24.1 Formative
Questions
What form of reproduction produces a new
organism from the lost body part of another
organism?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. budding
B. fertilization
C. parthenogenesis
D. regeneration
Chapter 24 Introduction to Animals
24.2 Formative
Questions
Which provides the strongest evidence for
the relationship between arthropods and
roundworms?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. shared
anatomical features
B. shared functional
characteristics
C. similar protein structure
D. similar embryological
development
Chapter 24 Introduction to Animals
24.2 Formative
Questions
Which is the dorsal surface of a hummingbird?
0%
0%
D
0%
C
A
B
C
D
B
A
0%
1.
2.
3.
4.
Chapter 24 Introduction to Animals
24.2 Formative
Questions
Which organism exhibits cephalization?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. jellyfish
B. snail
C. sponge
D. starfish
Chapter 24 Introduction to Animals
24.2 Formative
Questions
How is deuterostome development
different from protostome
development shown here?
A. A blastula does not form.
B. The coelom is
less advanced.
C. The gut is lined
with mesoderm.
D. The blastopore
becomes the anus.
0%
D
0%
C
0%
B
A
0%
1.
2.
3.
4.
A
B
C
D
Chapter 24 Introduction to Animals
24.3 Formative
Questions
Why are sponges most distantly related to
the rest of the animals?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. They are not multicellular.
B. They do not have
true tissues.
C. Their embryos have
a mesoderm.
D. They arose from a
different protist ancestor.
Chapter 24 Introduction to Animals
24.3 Formative
Questions
What is the term for organisms that remain
attached to one place?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. sessile
B. tactile
C. axiallary
D. sedentary
Chapter 24 Introduction to Animals
24.3 Formative
Questions
What provides the energy for the discharge
of a cnidarian’s nematocysts?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. muscle fibers
B. hydraulic forces
C. osmotic pressure
D. protein springs
Chapter 24 Introduction to Animals
24.3 Formative
Questions
Which is the dominant stage in the life cycle
of a sea anemone?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. bud
B. hydroid
C. medusa
D. polyp
Chapter 24 Introduction to Animals
Chapter Assessment
Questions
Identify the term that is used to
describe the evolutionary history
of a particular species.
A. genealogy
B. biology
C. phylogeny
D. paleontology
1.
2.
3.
4.
0%
D
0%
C
0%
B
A
0%
A
B
C
D
Chapter 24 Introduction to Animals
Chapter Assessment
Questions
Distinguish between asymmetry, radial
symmetry and bilateral symmetry and give
an example of each.
Chapter 24 Introduction to Animals
Chapter Assessment
Questions
Answer: Asymmetry – There is no symmetry or
balance in body structure and no shape.
Example: sponge
Radial symmetry – The animal’s body
can be divided along any plane through
a central axis into equal halves.
Example: jellyfish
Bilateral symmetry – The animal can be
divided into mirror image halves along
one plane. Example: dog
Chapter 24 Introduction to Animals
Chapter Assessment
Questions
Explain why it would be beneficial for a fish to
lay many eggs when fertilization is external.
Answer: Some of the eggs will float away, be
eaten or destroyed, so laying a large
number of eggs makes it more likely
that some will be fertilized and hatch.
Chapter 24 Introduction to Animals
Standardized Test
Practice
Which is not a characteristic that defines
all animals?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. carnivorous
B. eukaryotic
C. heterotrophic
D. multicellular
Chapter 24 Introduction to Animals
Standardized Test
Practice
At which stage is the developing
animal an embryo?
A
B
C
D
0%
0%
D
0%
C
A
0%
B
1.
2.
3.
4.
Chapter 24 Introduction to Animals
Standardized Test
Practice
Which reproduces by internal fertilization?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. bear
B. clam
C. fish
D. frog
Chapter 24 Introduction to Animals
Standardized Test
Practice
What is the most recent evolutionary
development exhibited by both arthropods
and echinoderms?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. a body cavity
B. a coelom
C. segmentation
D. protostome
development
Chapter 24 Introduction to Animals
Standardized Test
Practice
Which organisms are most closely related
to roundworms?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. sponges
B. cnidarians
C. flatworms
D. arthropods
Chapter 24 Introduction to Animals
Standardized Test
Practice
What characteristic do sponges and
cnidarians have in common?
0%
0%
0%
D
A
B
C
D
C
A
0%
1.
2.
3.
4.
B
A. body symmetry
B. single body opening
C. cell layers organized
into tissues
D. sessile attachment
to surfaces
Chapter 24 Introduction to Animals
Glencoe Biology Transparencies
Chapter 24 Introduction to Animals
Image Bank
Chapter 24 Introduction to Animals
Vocabulary
Section 1
invertebrate
external fertilization
exoskeleton
blastula
endoskeleton
gastrula
vertebrate
endoderm
hermaphrodite
ectoderm
zygote
mesoderm
internal fertilization
Chapter 24 Introduction to Animals
Vocabulary
Section 2
symmetry
ventral
radial symmetry
coelom
bilateral symmetry
pseudocoelom
anterior
acoelomate
posterior
protostome
cephalization
deuterostome
dorsal
Chapter 24 Introduction to Animals
Vocabulary
Section 3
filter feeder
polyp
sessile
medusa
cnidocyte
nematocyst
gastrovascular cavity
nerve net
Chapter 24 Introduction to Animals
Animation
 Cell Differentiation in Animal
Development
 Visualizing Protostome and
Deuterostome Development
 A Sponge
 A Cnidarian
Chapter 24 Introduction to Animals
Chapter 24 Introduction to Animals
Chapter 24 Introduction to Animals
Chapter 24 Introduction to Animals