InvertebratesInvertebrates

Look at all the pretty Look at all the pretty animals…..awwwwww!animals…..awwwwww!All invertebrates included except All invertebrates included except arthropodsarthropods

How Did Animal Life How Did Animal Life Begin?Begin?

Many scientists believe colonial protists Many scientists believe colonial protists got together and formed a gastrula-like got together and formed a gastrula-like animal with a digestive cavityanimal with a digestive cavity

Cambrian Explosion-first evidence of Cambrian Explosion-first evidence of huge animal diversityhuge animal diversity

Huge change in animal diversity between Huge change in animal diversity between the Precambrian and Cambrian periodsthe Precambrian and Cambrian periods

Cambrian ExplosionCambrian Explosion

Many hard-bodies animals with shells developed during this period.

Body CavitiesBody Cavities

Coelom-fluid filled cavity that is Coelom-fluid filled cavity that is completely lined by tissue that originated completely lined by tissue that originated from the embryo mesoderm tissuefrom the embryo mesoderm tissue

Coelomate-fluid filled cavity, no direct Coelomate-fluid filled cavity, no direct organ contactorgan contact

Pseudocoelom-fluid filled cavity in direct Pseudocoelom-fluid filled cavity in direct contact with body cavitycontact with body cavity

Acoelomate-no body cavityAcoelomate-no body cavity

Coelomates are divided Coelomates are divided into 2 groups.into 2 groups.

Protostomes Deuterostomes

Coelom forms from the solid masses in the embryo

Coelom forms from a portion of the digestive tube

Annelids and Mollusks

Echinoderms and Chordates (Us)

VocabularyVocabulary

Invertebrates-No backboneInvertebrates-No backbone Vertebrates-backboneVertebrates-backbone Blastula-hollow ball of cellsBlastula-hollow ball of cells Gastrula-hollow ball of cells, folded in to Gastrula-hollow ball of cells, folded in to

create an inner cavitycreate an inner cavity

Sponges_Phylum PoriferaSponges_Phylum PoriferaKey IdeasKey Ideas

Simplest AnimalSimplest Animal Adults are sessile-can’t move on their Adults are sessile-can’t move on their

ownown Lack true tissues and organs, most are Lack true tissues and organs, most are

unspecializedunspecialized Incomplete digestive systemIncomplete digestive system Body consists of two layers separated by Body consists of two layers separated by

a jelly-like materiala jelly-like material

PoriferaPorifera

Outer layer protects the interior and has many holes Outer layer protects the interior and has many holes through which water can enter the spongethrough which water can enter the sponge

Inner layer are lined with collar cells, which have Inner layer are lined with collar cells, which have flagellaflagella

Amoebocytes wander through the jelly-like material and Amoebocytes wander through the jelly-like material and pick up food from the collar cells for digestions, pick up food from the collar cells for digestions, transport oxygen, dispose of waste and can change transport oxygen, dispose of waste and can change into other cells for supportinto other cells for support

Have special chemical defenses to protect from Have special chemical defenses to protect from predators, disease organisms, humans use these predators, disease organisms, humans use these chemicalschemicals

Related closely to protists and are the earliest animals.Related closely to protists and are the earliest animals.

Sponges_Phylum PoriferaSponges_Phylum Porifera

Cnidarians- Phylum Cnidarians- Phylum Cnidaria Key IdeasCnidaria Key Ideas

Radial symmetry, most do not have a head and are Radial symmetry, most do not have a head and are sessilesessile

Tentacles with stinging cells called cnidocytesTentacles with stinging cells called cnidocytes Has poisonous barbs called nematocysts, that fire Has poisonous barbs called nematocysts, that fire

when touched, once prey has been captured, the when touched, once prey has been captured, the tentacles move it to the gastovascular cavitytentacles move it to the gastovascular cavity

Has basic tissues, nerve sensing functions and a Has basic tissues, nerve sensing functions and a gastrula stage of embryonic developmentgastrula stage of embryonic development

Has polyp form and medusa formsHas polyp form and medusa forms Incomplete digestive systemIncomplete digestive system

Two formsTwo forms

Polyp-cylindrical body with tentacles Polyp-cylindrical body with tentacles radiating from one end, sessileradiating from one end, sessile

Medusa- umbrella shaped form with Medusa- umbrella shaped form with fringed tentacles on the lower edge, fringed tentacles on the lower edge, move freelymove freely

Some cnidarians exist in both forms and Some cnidarians exist in both forms and some one or the othersome one or the other

Types of CnidariansTypes of Cnidarians

Hydrozoa- hydras, some corals, Hydrozoa- hydras, some corals, Portuguese man-o-warPortuguese man-o-war

Scyphozoa-jellyfishScyphozoa-jellyfish Anthozoa- sea anemones and most Anthozoa- sea anemones and most

coralscorals

Cnidarians-ScyphozoansCnidarians-Scyphozoans

Cnidarians-Box jellyfishCnidarians-Box jellyfish

Most deadly jellyfish, can kill a person!

HydrozoansHydrozoans

Portuguese Man-O-War, Looks like a jellyfish, but it is actually a colony of polyps like this one

AnthozoansAnthozoans

Flatworms-Phylum Flatworms-Phylum Platyhelminthes Platyhelminthes

Flatworms-small,leaflike or ribon likeFlatworms-small,leaflike or ribon like

Bilateral symmetry-mirror image right and Bilateral symmetry-mirror image right and left sidesleft sides

3 tissues-ectoderm-outside, mesoderm-3 tissues-ectoderm-outside, mesoderm-middle, endoderm-insidemiddle, endoderm-inside

Incomplete digestive system-1 way in/outIncomplete digestive system-1 way in/out

Acoelomate-no body cavityAcoelomate-no body cavity

Classes of FlatwormsClasses of Flatworms

Class Turbellaria-planarians, free-living, Class Turbellaria-planarians, free-living, non-parasitic, live in moist environmentsnon-parasitic, live in moist environments

Class Trematoda-flukes, parasites that Class Trematoda-flukes, parasites that absorb nutrients from the body of a host absorb nutrients from the body of a host harming it, may have more than 1 hostharming it, may have more than 1 host

Class Cestoidea-tapeworms, parasitic, Class Cestoidea-tapeworms, parasitic, live inside 1 or more hosts, contain flat live inside 1 or more hosts, contain flat segments each with reproductive organssegments each with reproductive organs

Class TurbellariaClass Turbellaria

Class TrematodaClass Trematoda

Class CestoideaClass Cestoidea

Ewwwww, tapeworms!Ewwwww, tapeworms!

Roundworms-Phylum Roundworms-Phylum NematodaNematoda

Roundworms-small, cylindrical worms with pointed Roundworms-small, cylindrical worms with pointed heads and tapered tailsheads and tapered tails

3 tissue layers3 tissue layers Complete digestive tract with mouth and anusComplete digestive tract with mouth and anus Digestion highly specializedDigestion highly specialized Free-living and non-parasitic roundworms are the most Free-living and non-parasitic roundworms are the most

abundant but parasitic types are hookworm, pinworm, abundant but parasitic types are hookworm, pinworm, threadworm and trichinosisthreadworm and trichinosis

Many are introduced through poorly cooked pork or Many are introduced through poorly cooked pork or walk barefoot in infected areaswalk barefoot in infected areas

RoundwormsRoundworms

Trichinosis- disease caused by a roundworm contracted by eating undercooked pork and other meat infected with it

Phylum Rotifera-Key Phylum Rotifera-Key IdeasIdeas

Rotifers-tiny animals that have a Rotifers-tiny animals that have a complete digestive tractcomplete digestive tract

They have a crown of cilia around their They have a crown of cilia around their mouths.mouths.

Yay…rotifers!Yay…rotifers!

Phylum AnnelidaPhylum Annelida

Segmented wormsSegmented worms Closed circulatory system-when blood is Closed circulatory system-when blood is

contained in vesselscontained in vessels Bilateral symmetryBilateral symmetry CoelomateCoelomate Class Polychaeta-sandworms, bristlewormsClass Polychaeta-sandworms, bristleworms Class Oligochaeta-EarthwormsClass Oligochaeta-Earthworms Class Hirudinea-leechesClass Hirudinea-leeches

Class Polychaeta-Class Polychaeta-sandworms and otherssandworms and others

Class Oligochaeta-Class Oligochaeta-earthwormsearthworms

If the soil is a rockin’ don’t come a knockin’!

Class Hirudinea-LeechesClass Hirudinea-Leeches

Land Leeches

Phlylum MolluscaPhlylum Mollusca

Muscular mass of tissue called a foot and Muscular mass of tissue called a foot and a multifunctional structure called the a multifunctional structure called the mantlemantle

Mantle-outgrowth of the body surface Mantle-outgrowth of the body surface that drapes over the animal, produces that drapes over the animal, produces the shell in clams and snailsthe shell in clams and snails

Gills are housed in the mantle cavity in Gills are housed in the mantle cavity in aquatic speciesaquatic species

MollusksMollusks

Radula-unique rasping organ, scrapes Radula-unique rasping organ, scrapes food into mouthfood into mouth

Have a true coelom but an open Have a true coelom but an open circulatory systemcirculatory system

ClassesClasses

Class Gastropoda-largest group, most Class Gastropoda-largest group, most have a single shell, usually spiralled, have a single shell, usually spiralled, most are aquatic, land snails, slugs, sea most are aquatic, land snails, slugs, sea slugs, aquatic snailsslugs, aquatic snails

Class Bivalvia-clams, oysters, mussels, Class Bivalvia-clams, oysters, mussels, scallops; hinged shell in 2 halves, feed by scallops; hinged shell in 2 halves, feed by pumping water over their gills into and pumping water over their gills into and out of siphonsout of siphons

ClassesClasses

Class Cephalopoda- squid, octopus, Class Cephalopoda- squid, octopus, chambered nautilus, cuttlefish;small chambered nautilus, cuttlefish;small internal shells except octopus internal shells except octopus

Nautius has external shellNautius has external shell All marine predators, very intelligent with All marine predators, very intelligent with

the most complex brains and eyes of the the most complex brains and eyes of the invertebrate worldinvertebrate world

Class GastropodaClass Gastropoda

Class BivalviaClass Bivalvia

Clam larvae

Class CephalopodaClass Cephalopoda

Nautilis-very old

Phylum EchinodermataPhylum Echinodermata

Lack body segmentsLack body segments Rough or spiny surfaceRough or spiny surface Contain a tough endoskeletonContain a tough endoskeleton Water vascular system-network of fluid-filled Water vascular system-network of fluid-filled

canals that branch into tube feet that function canals that branch into tube feet that function in locomotion, feeding and respirationin locomotion, feeding and respiration

Many echinoderms can regenerate lost parts Many echinoderms can regenerate lost parts and even internal organsand even internal organs

ClassesClasses

Class Echinoidea-sea urchinsClass Echinoidea-sea urchins Class Asteroidea-sea starsClass Asteroidea-sea stars Class Crinoidea- sea liliesClass Crinoidea- sea lilies Class Holothuroidea- sea cucumbersClass Holothuroidea- sea cucumbers Class Concentricyloidea-sea daisiesClass Concentricyloidea-sea daisies

EchinodermsEchinoderms