Download Life Science Chapter 13: Introduction to Animals

Life Science Chapter 13: Introduction to Animals
Section 13.1: What is an animal? (p.344-347)
Animal Characteristics
- Animals cannot make their own food (some eat
plants, some eat animals, some eat both).
- Animals digest their food in order to for their bodies
to use the food.
- Animals move from place to place ( food, mates,
escape from enemies).
- Animals have many cells.
- Animals are eukaryotic (nucleus and organelles
surrounded by membrane).
Animal Classification
- scientists have identified and named more than 1
million species of animals
- some est. there are 3-30 million more to identify and
name
- Vertebrate or invertebrate?

Vertebrates - animals with backbones
 Fish, humans, birds, snakes

Invertebrates – animals that lack a backbone
 97% of all animals
 Sponges, jellyfish, worms, insects,
clams
- Symmetry

The arrangement of the animals body parts

Radial symmetry – animals that have body parts
arranged in a circle around a central point (sea
anemones)
- Bilateral Symmetry
 An animal with body parts arranged in the same
way on both sides of its body has bilateral
symmetry (butterfly)
 Bilateral means two sides.
 Assymmetrical – organisms with no definite
shape (sponges)
Section 13.3: Sponges and Cnidarians (p. 350-356)
Sponges
- Characteristics of Sponges
 All live in water, most in warm shallow salt
water near the coast
 Few live in freshwater
 Many shapes, sizes (from size of marble to size
of car) and colors
 Some have radial symmetry, most asymmetrical
 Sessile - live attached to one place
 Live in colonies
 Don’t make their own food
 Body is covered with pores or small openings
 Phylum name is Porifera – “pore-bearing”
- Obtaining Food
 Filter feeders – organisms that obtain their food
by filtering water
 Bacteria, algae, protozoans are filtered through
pores
 Collar cells with flagella that line the inside of the
sponge help move water
 The filtering brings oxygen to the cells and
removes wastes
 Spicules, spongin or both make up skeletons of
sponges
- Reproduction
 Reproduce asexually by forming buds
 Reproduce asexually by regeneration
 Reproduce sexually by egg and sperm
 Some sponges have separate sexes
 Most sponges are hermaphrodites which produce
both sperm and eggs
 Sperm are released in water and carried by
currents to other sponges to fertilize the eggs
 Fertilized egg develops into a larva
 Sponge larva have cilia
 Larva finally settles where it will grow into an adult
- Origin of Sponges
 600 million years ago in the Cambrian period
 Sponges have not evolved into other animal
species
Cnidarians
- sea anemones, coral, Portuguese man-of-war
- Latin for “stinging cells”
- Most live in salt water
- Jellyfish live individually, coral live in colonies of
polyps
- Radially symmetrical
- Have two cell layers which form tissues
- Have a digestive cavity
- Have tentacles that sting to help capture food
- Two Body Plans
 The polyp is shaped like a vase and is sessile
(hydra)
 The medusa is bell-shaped and free-swimming
(jellyfish)
 Some cnidarians go through both polyp and
medusa stages
 Cnidarians have a nerve net that carries impulses
and connects all parts of the organism
- Reproduction
 Produce asexually and sexually
 Polyps produce buds and can also reproduce
sexually
 Medusa produce eggs and sperm and release them
into water
 Medusa fertilized eggs develop into larvae
 Medusa larvae grow into polyps
 Young medusa polyps bud
Origin of Cnidarians
 More than 600 million years ago in the Precambrian
era
 Scientists think the first were medusa
 Most cnidarian fossils are fossils of coral
- Cnidarians and Coral Reefs
 Coral reefs are found in warm waters between
latitudes of 30 degrees north and 30 degrees south
 Sea anemones attach to dead coral
 Largest coral reef is the Great Barrier Reef of Australia
 Coral reefs protect beaches and shoreline from being
washed away from waves
 Many organisms live on or near coral reefs
 Coral reefs provide recreation to scuba divers and
snorkelers
Section 13.4: Flatworms and Roundworms (p.357-363)
Flatworms
- Worms are invertebrates with soft bodies and
bilateral symmetry
- Worms live in many different environments
- Worms have 3 different tissue layers that form organs
-Type of Flatworms
 Flatworms have flattened bodies
 Members of this phylum include planarians and
tapeworms
 Some are free-living but most are parasitic
 Most live in salt water
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Planarians
Triangle-shaped head with two eyespots
Mouth on the ventral (bottom) side of the body
Pharynx connects mouth to digestive tract
Feeds on small organisms and dead organisms
Most live in fresh water, under rocks, or on plant
material, even on moist land
3mm to 30cm in length
Cilia help the planarians move
Reproduce asexually by division or by regeneration
Reproduce sexually by releasing eggs or sperm
Some planarians are hermaphrodites
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Tapeworms
Parasitic members of the phylum Platyhelminthes
Use hooks and suckers to attach to host’s intestines
No mouth or digestive system
Digested food in the intestine of the host is absorbed
Grow new segments behind the head
May grow as long as 12 meters
Each segment produces eggs and sperm
Once segment is filled with fertilized eggs, it breaks
off and passes out of the host’s body
 If fertilized egg eaten by another host, the egg can
hatch and develop into a new worm
Roundworms
- causes heartworm disease in dogs
- Phylum Nematoda is the largest phylum of worms
- More than half million species of Nematoda
- Found in soil, animals, plants, fresh and salt water
- Most free-living, some parasitic
- Structure is a tube within a tube
- Have a mouth and anus
- Types of Roundworms
 Ascaris (hookworm)
 Parasite in humans, pigs, horses
 Humans contract it from walking barefoot in dirt or
fields
 Masses of the worms can block intestines and cause
death
 Trichinella
 Causes the disease trichinosis
 Undercooked pork may have Trichinella cysts
 Heartworms
 Enter dog through a mosquito bite
 Worms move to the heart, where they grow and
reproduce
 Worms can block valves of the heart
- Flatworms and roundworms have bilateral symmetry
- Flatworms and roundworms have 3 tissue layers
- Flatworms and roundworms probably evolved in the
sea
Life Science Chapter 13: Introduction to Animals
Section 13.1: What is an animal? (p.344-347)
Animal Characteristics
- Animals cannot make their own food
- Animals digest their food in order to for their bodies
- Animals move from place to place
- Animals have many
- Animals are eukaryotic
Animal Classification
- scientists have identified and named more than
- some est. there are 3-30 million more to identify and
name
- Vertebrate or invertebrate?

Vertebrates - animals with
 Fish, humans

Invertebrates – animals that lack a

of all animals
 Sponges, jellyfish
- Symmetry

The arrangement of the

Radial symmetry – animals that have body parts
arranged in a
- Bilateral Symmetry
 An animal with body parts arranged in the same
way on both sides of its body has
 Bilateral means
 Assymmetrical – organisms with
Section 13.3: Sponges and Cnidarians (p. 350-356)
Sponges
- Characteristics of Sponges
 All live in water, most in warm
 Few live in
 Many shapes, sizes
 Some have radial symmetry,
 Sessile  Live in
 Don’t make their own
 Body is covered with
 Phylum name is Porifera –
- Obtaining Food
 Filter feeders – organisms that obtain their food
by

are filtered
through pores
 Collar cells with
that line the inside
of the sponge
 The filtering brings
to the cells and
removes
 Spicules, spongin or both make up
- Reproduction
 Reproduce asexually by
 Reproduce asexually by
 Reproduce sexually by
 Some sponges have
 Most sponges are hermaphrodites which produce
 Sperm are released in water and carried by
currents to other sponges to
 Fertilized egg develops into a
 Sponge larva have
 Larva finally settles where it will
- Origin of Sponges
 600 million years ago in the
 Sponges have not evolved into other
Cnidarians
- sea anemones, coral, Portuguese man-of-war
- Latin for
- Most live in
- Jellyfish live
coral live in
-
Radially
Have two cell layers which form
Have a digestive
Have tentacles that sting to
- Two Body Plans
 The polyp is shaped like a
 The medusa is
 Some cnidarians go through both
 Cnidarians have a nerve net that carries
- Reproduction
 Produce
 Polyps produce
and can also reproduce
 Medusa produce
and release them
into water
 Medusa fertilized eggs develop into larvae
 Medusa larvae
 Young medusa
Origin of Cnidarians
 More than 600 million years ago in the
 Scientists think the first were medusa
 Most cnidarian fossils are fossils of
- Cnidarians and Coral Reefs
 Coral reefs are found in warm waters between
latitudes of
 Sea anemones attach to
 Largest coral reef is the
 Coral reefs protect beaches and shoreline from being
 Many organisms live on or near
 Coral reefs provide recreation to
Section 13.4: Flatworms and Roundworms (p.357-363)
Flatworms
- Worms are
with soft bodies and
- Worms live in many different
- Worms have
layers that form organs
-Type of Flatworms
 Flatworms have
 Members of this phylum include
 Some are
 Most live in

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
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




most are
Planarians
Triangle-shaped head with
Mouth on the
Pharynx connects mouth to
Feeds on small organisms and
Most live in fresh water, under rocks, or on plant
material,
3mm to 30cm in
Cilia help the
Reproduce asexually by
Reproduce sexually by
Some planarians are








Tapeworms
Parasitic members of the phylum
Use hooks and suckers to attach
No mouth or
Digested food in the intestine of the host is
Grow new segments behind the
May grow as long as
Each segment produces
Once segment is filled with fertilized eggs,
 If fertilized egg eaten by another host,
Roundworms
- causes heartworm disease
- Phylum Nematoda is the largest
- More than half million species of Found in soil,
animals, plants, fresh and salt water
- Most
- Structure is a
- Have a
- Types of Roundworms
 Ascaris
 Parasite in
 Humans contract it from walking
 Masses of the worms can
 Trichinella
 Causes the disease
 Undercooked pork may have
 Heartworms
 Enter dog through a
 Worms move to the heart,
 Worms can block
- Flatworms and roundworms have
- Flatworms and roundworms have
- Flatworms and roundworms probably