Chapter 24 and 25Chapter 24 and 25

Sponges, Sponges, Cnidarians, Cnidarians,

Flatworms, and Flatworms, and RoundwormsRoundworms

Phylum Porifera (“pore-bearer”)Phylum Porifera (“pore-bearer”)

~Includes all ~Includes all sponges (grantia, sponges (grantia, scypha, & scypha, & leucosolenia)leucosolenia)

Basketball sponge Cinachyra sponge

Knob sponge

• Simplest animalsSimplest animals• AsymmetricalAsymmetrical

Phylum PoriferaPhylum Porifera AquaticAquatic Sessile - can’t move Sessile - can’t move

from place to placefrom place to place Filter feedersFilter feeders

Red sponge

Volcano sponge

Phylum PoriferaPhylum Porifera

Reproduce both Reproduce both sexually and…sexually and…

AsexuallyAsexually

* Regeneration – * Regeneration –

reattachreattach

* Budding - grow * Budding - grow

new spongesnew sponges

Dead man’s finger sponge

Phylum PoriferaPhylum Porifera Hermaphrodites -Hermaphrodites -

produce both eggs produce both eggs and spermand sperm

Sponge dumping gametes

Phylum Porifera

Phylum PoriferaPhylum Porifera Osculum - opening on some Osculum - opening on some

spongessponges Spicules - sharp, hard, needle-Spicules - sharp, hard, needle-

like structures - attachmentlike structures - attachment

Phylum Cnidaria Phylum Cnidaria (“nettles” / tentacles)(“nettles” / tentacles)

Includes jellyfishes, corals, Includes jellyfishes, corals, sea anemones & hydrassea anemones & hydras

Brain coralJellyfishes

Green anemone

Phylum CnidariaPhylum Cnidaria

AquaticAquatic Radial symmetryRadial symmetry

Flower pot coral

Purple anemone

Phylum CnidariaPhylum Cnidaria

Nerve net - a simple Nerve net - a simple nervous systemnervous system

Sun coral

Torch coral

Nematocysts - tubes in Nematocysts - tubes in tentacles - contains poisontentacles - contains poison

Gastrovascular cavity - Gastrovascular cavity - primitive stomachprimitive stomach

Monterey, CAMonterey, CA

Phylum CnidariaPhylum Cnidaria Two basic body formsTwo basic body forms

Polyp - tube shaped bodyPolyp - tube shaped body Medusa - body shaped Medusa - body shaped

like an umbrellalike an umbrella

Medusa

Red cauliflower coral

Moon jelly

Club tipped anemone

Pineapple coral

Staghorn coral

Sea anemone

CoralsCorals

Hydra releasing an egg

Hydra releasing sperm

Budding hydra

Reproduce:Sexually - hermaphroditesAsexually - budding

PHYLUM: PLATYHELMINTHESPHYLUM: PLATYHELMINTHES(“flat worms”)(“flat worms”)

Includes:Includes: Tapeworms & liver flukes Tapeworms & liver flukes

(Parasitic)(Parasitic) Planarians (Free-living)Planarians (Free-living)

Bilateral symmetryBilateral symmetry

(PHYLUM: PLATYHELMINTHES)(PHYLUM: PLATYHELMINTHES)

Some have eyespotsSome have eyespots Scolex - head of a Scolex - head of a

tapewormtapeworm Proglottid - body partProglottid - body part

LIFE CYCLES: LIFE CYCLES: May involve two or more hosts.May involve two or more hosts.

(TAPEWORM LIFE CYCLE)

• Most have Most have digestive systemsdigestive systems

Exception: Exception: TapewormsTapeworms

Life Cycle of Life Cycle of a Liverflukea Liverfluke

PHYLUM: NEMATODAPHYLUM: NEMATODA(“Thread” / Roundworms)(“Thread” / Roundworms)

PHYLUM: NEMATODAPHYLUM: NEMATODA

Includes:Includes: Ascaris (Roundworms)Ascaris (Roundworms) Pin wormsPin worms Trichina wormsTrichina worms HookwormsHookworms

The above are parasiticThe above are parasitic Most are free-livingMost are free-living

PHYLUM: NEMATODAPHYLUM: NEMATODA

Bilateral Bilateral symmetrysymmetry

Some are Some are hermaphroditeshermaphrodites

LIFE CYCLE OF A LIFE CYCLE OF A ROUNDWORMROUNDWORM

PARASITIC WORMSPARASITIC WORMS

WORMWORM HOW HOW ACQUIREDACQUIRED

INVADESINVADES

Tapeworm / Tapeworm /

RoundwormRoundworm

Eating raw meatEating raw meat IntestinesIntestines

HookwormHookworm Walking Walking barefootbarefoot

LungsLungs

Liver flukeLiver fluke Eating raw fishEating raw fish LiverLiver

Trichina wormTrichina worm Eating raw porkEating raw pork MusclesMuscles