Download Characteristics ~

Kingdom Animalia
What
characteristics
define an animal?
~ Characteristics ~

Multicellular

Eukaryotic with no cell walls

Heterotrophs (consumers)
~ Characteristics ~

Have a nervous system to respond to their
environment

Locomotion relates to ability to obtain food

Most animals develop from a zygote
Reproduction:
 Fertilization occurs when the sperm
penetrates the egg to form a fertilized egg
cell called the zygote.
 Internal fertilization
 External fertilization
 Asexual reproduction means that a single
parent produces offspring that are
genetically identical to itself.
 Budding
 Fragmentation
 Regeneration
 Parthenogenesis
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.
Gastrula - A single layer of cells
surrounding a fluid-filled space
forming a hollow ball of cells.
~ Developmental Characteristics ~

The gastrula is made up of three parts:
– Ectoderm, a layer of cells on the outer surface
of the gastrula, grows and divides developing
into skin and nervous tissue.
– Endoderm, a layer of cells lining the inner
surface of the gastrula, develops into the
lining of the animal’s digestive tract.
– Mesoderm, made up of two layers of cells
lying between the ectoderm and endoderm,
forms muscles, reproductive organs and
circulatory vessels.
~ Developmental Characteristics ~

Animals that develop a mouth from the
indented space in the gastrula are
protostomes.

Animals that develop an anus from the
opening in the gastrula are
deuterostomes.
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.
~ Body Plans ~

Animals that are
irregular in shape are
asymmetrical.

Animals that are
regular in shape are
symmetrical.
~ Body Plans ~

An animal has radial symmetry if it
can be divided along any plane,
through a central axis, into equal
halves.

An animal has bilateral symmetry if
it can be divided down its length
into similar right and left halves
forming mirror images of each other.
Which figure has bilateral symmetry?
Which has radial symmetry?
~ Body Plans ~

Acoelomates – animals have three cell
layers with a digestive tract but no body
cavities.

Pseudocoelomates – animals with a fluidfilled body cavity partly lined with
mesoderm.

Coelomates – animals with a body cavity
completely surrounded by mesoderm.
Body Cavities
 Coelomates
 Have a fluidfilled cavity
with tissue
formed from
mesoderm
that lines and encloses the organs in the
coelom
Body Cavities
 Pseudocoelomates
 Have a fluid-filled
body cavity that
develops between
the mesoderm
and endoderm rather than developing
the
entirely within the mesoderm
Body Cavities
 Acoelomates
 Have solid bodies
without a fluidfilled body cavity
between the gut
and the body wall
~ Protection and Support ~

Though not all animals have a skeleton,
those that do can be divided into two
groups:
– Those with an exoskeleton – a hard,
waxy coating on the outside of the body
that protects internal organs, provides a
framework for support, and a place for
muscle attachment.
– Those with an endoskeleton – support
framework within the body that protects
some organs and a brace for muscles to
pull against.
Cephalization
 The tendency to concentrate nervous
tissue and sensory organs at the anterior
end of the animal
~Invertebrates~

8 main phyla

No backbones

95% of all animals are in this group
~Invertebrate
Phylum Porifera~

Sponges

simplest form of animal life

live in water

Do not move around

no symmetry

Pores (holes) all over body
~Invertebrate
Phylum Porifera~

Filter Feeders: a sponge filters particles of
food from water using collar cells and then
pumps the water out the osculum.
~Invertebrate
Phylum Porifera~

Examples: Tube
Sponge, Glass
Sponge, Sea Sponge
~Invertebrate
Phylum Cnidaria~

Live in water

Most have tentacles

catch food with stinging cells

gut for digesting
~Invertebrate
Phylum Cnidaria~
 2 different
shapes
 Medusa - like a
jellyfish
 Polyp - like a
hydra
~Invertebrate
Phylum Cnidaria~

Examples Jellyfish, Hydra,
sea anemones, and
corals
~Invertebrate
Phylum Platyhelminthes ~
 Flatworms
 Flat, ribbon-like body
 Live in water or are parasites
 bilateral symmetry
~Invertebrate
Phylum Platyhelminthes ~
 Examples: Planaria
 eyespots detect light
 food and waste go
in and out the same
opening
~Invertebrate
Phylum Platyhelminthes ~
 Examples:
Tapeworm
 Parasite that
lives in intestines
of host
absorbing food
~Invertebrate
Phylum Platyhelminthes ~
 Examples: Fluke
 parasite
 lives inside
of host
~Invertebrate
Phylum Nematoda ~

Roundworms
– Round, tubular body
– small or microscopic
– bilateral symmetry
– have both a mouth and anus
– Live in water or are parasites
~Invertebrate
Phylum Nematoda ~

Examples:
– Hookworm
– Trichinella
~Invertebrate
Phylum Mollusca ~

Soft bodies

Hard Shells

Live on land or in water

have a circulatory system and a complex
nervous system.

Important food source for humans
~Invertebrate
Phylum Mollusca ~
Class Gastropoda
– snails and slugs
– may have 1 shell
– stomach-footed move on stomach
~Invertebrate
Phylum Mollusca ~
Class Bivalves
– 2 shells hinged
together
– clams, oysters,
scallops and
mussels
~Invertebrate
Phylum Mollusca ~
Class Cephalopods
–squids and octopuses
–internal mantel
~Invertebrate
Phylum Annelida ~
–Segemented worms
– Body divided into
segments(sections)
– Live in water or
underground
– have a nervous and circulatory system
~Invertebrate
Phylum Annelida ~

Class Earthworms

eat soil and
breakdown
organic matter,
wastes provide
nutrients to soil
~Invertebrate
Phylum Annelida ~
Class bristleworms
~Invertebrate
Phylum Annelida ~
 Class

leeches
parasites that feed on blood of other animals
~Invertebrate
Phylum Echinodermata ~

Hard, spiny skin

Live in salt water

Radial symmetry

name means ‘spiney skinned’

endoskeleton
~Invertebrate
Phylum Echinodermata ~

Examples: seastar, sea urchin, sand dollar
and sea cucumber
~Invertebrate
Phylum Arthropoda ~

Body divided into sections/segments

Exoskeleton

Jointed legs

well developed nervous system

largest group of organisms on earth
~Invertebrate
Phylum Arthropoda ~

3 subphylums:

Classified into classes according to the
number of legs, eyes and antennae they
have.
~Invertebrate
Phylum Arthropoda ~
Subphylum Chilicerata
is divided into 3 classes
Arachnida – spiders, scorpions, ticks, mites
Merostomata – horseshoe crabs
Pycnogonida – sea spiders
~Invertebrate Phylum
Arthropoda ~ Subphylum Chilicerata
 Class
– Arachnida

no antennae

4 pairs of legs

2 body regions - cephalothorax & abdomen

spiders, scorpions, mites & ticks
~Invertebrate Phylum
Arthropoda ~ Subphylum Chilicerata
 Class

Merostomata
Horseshoe crabs
– Ancient group of species
– Changed little over 350 million years
– Aquatic, mostly found on Atlantic & gulf
coasts of United States.
~Invertebrate Phylum
Arthropoda ~ Subphylum Chilicerata
 Class
Pycnogonida
– Sea spider
~Invertebrate Phylum
Arthropoda ~ Subphylum - Crustacea
5 Classes
 Aquatic ones have gills

2 antennae

2 body regions or segmented

Shrimp, lobsters, crabs, barnacles, isopods

Many species taste delicious in butter
 Subphylum
Uniramia: 3 classes

Class Insecta (insects)

Class Chilopoda (Centipedes)

Class Diplopoda (Millipedes)
~Invertebrate Phylum
Arthropoda ~ Subphylum Uniramia
 Class
Insecta

antennae

3 pairs of legs

3 body regions - head, thorax & abdomen

grasshoppers, ants, butterflies, bees
~Invertebrate
Phylum Arthropoda ~ Subphylum Uniramia
 Class
Diplopoda

Millipedes

segmented animals

Have 2 pairs of legs per segment

Primarily herbivores & decomposers
~Invertebrate Phylum
Arthropoda ~ Subphylum Uniramia
 Class
Chiopoda

Centipedes Usually terrestrial carnivores

Have 1 pair of antennae

Are often poisonous, using modified front
claws to immobilize prey
~ Phylum Chordata ~ subphylum Vertebrata
5 classes
 Fish
 Mammals
 Reptiles
 Amphibians
 Birds