Phylum Mollusca • the second largest

phylum of animals

• includes the octopus and the clam

gastropod gastro pod

stomach foot

cephalopod cephalo pod

head foot

octopus octo pus

eight foot

• univalve = “one shell”

• bivalve = “two shells”

Mollusk Shells

• mantle

• siphon

• filter feeders

Clams

Phylum Arthropoda

• highly diverse

• more species than any other animal phylum

mollusks 75,000 species

worms 30,000 species

cnidarians 10,000 species

sponges 5,000

species

other invertebrates 8,000 species

chordates 40,000 species

echinoderms 5,500

species

arthropods

• significant effect on our world

• beneficial effects

• harmful effects

Phylum Arthropoda

joint foot

arthropoda arthro poda

• jointed appendages

Phylum Arthropoda

jointed legs

antennae

• exoskeleton

• a hard, nonliving covering that supports and protects the animal

Phylum Arthropoda

Class Insecta • three body segments

thorax

head

abdomen

• three body segments

• three pairs of legs

• wings

Class Insecta

wings

• three body segments

• three pairs of legs

• wings

• compound eyes

Class Insecta

cerci

antennae

Insect Anatomy • heart

hearts artery

• heart

• excretory tubules

Insect Anatomy

hearts artery

excretory tubules

• heart

• excretory tubules

• open circulatory system

• tracheae

• spiracles

Insect Anatomy

tracheae

spiracles

insect killer

insecticide insecticide insecticide

molt • to shed

change form

metamorphosis meta metamorphosis

Metamorphosis

• incomplete metamorphosis

• complete metamorphosis

Incomplete Metamorphosis

• egg

• nymph

• adult

egg

nymph

adult

A nymph is an immature stage that looks just like the adult, but is smaller and isn’t

able to reproduce yet.

Complete Metamorphosis

• egg

• larva

• pupa

• adult

egg

larva

pupa

A larva is an immature stage of complete metamorphosis.

It is usually a very active stage.

The pupa stage is the resting stage of complete

metamorphosis.

Pupa Stage • cocoon = moth

• chrysalis = butterfly

egg

larva

adult pupa

• a three-part body

• three pairs of legs

• wings

Class Insecta

Class Crustacea • a two-part body

• more than three pairs of legs

Classes Chilopoda and Diplopoda

• centipedes

• millipedes

• a long, segmented body

Chilopoda

• centipedes

• one pair of legs per segment

Diplopoda

• millipedes

• two pairs per segment

centi milli

hundred thousand

diplopoda diplo

feet double

poda

Class Arachnida • a two-part body

• four pairs of walking legs

Spin Silk • for making webs

• for wrapping up prey

• for egg cases

Echinoderms • spiny skin

• radial symmetry

• water vascular system