Invertebrate Animals

Phyla:• Phylum Porifera• Phylum Cnidaria• Phylum Platyhelminthes• Phylum Nematoda

Cnidaria

Porifera

Nomura Jellyfish

Platyhelminthes

Nematoda

Invertebrate Animals

• Phylum Mollusca• Phylum Annelida• Phylum Arthropoda• Phylum

Echinodermata

Mollusca

Annelida

Arthropoda

Echinodermata

Polychete worm

Taxonomy

• Kingdom – Animalia• Subkingdom – Parazoa (lacks tissues)

• Phylum – Porifera (Pore-bearing)

Branching Tube Sponge

Stove Pipe Sponge

Vase Sponges

Barrel Sponges

Ball Sponges

Rope Sponges

Characteristics

o Simplest of all animals

o Most are marine

o Saltwater sponges - brightly colored

o Freshwater sponges - small and dull green color

o Size – 2 meters to 2 cm

o Skeleton of protein fibers called spongin or spicules.

Sponge Skeletons

SPONGIN

Silica Spicules

Limestone Spicules

Sponge Skeletons

SPICULESVENUS FLOWE

R BASKET

Characteristicso Have pores all over

their bodies

o Water enters through pores bringing in food and oxygen

o Osculum – large opening at the top where excess water leaves

oAsymmetrical

Water Flow Through the

Sponge

WATER IN

WATER OUT

Osculum

Movement

oSessile as adults (attach to rocks)

oFree-swimming larval stage

• Choanocytes line the gastrovascular cavity & capture food

• Amebocytes digest & distribute food

o Filter feeders on planktonNutrition:

• Choanocytes (collar cells) line inside of body cavity

• Have flagella that spins to pull in water & food

• Collar traps plankton (food) from water

oAmebocytes:• Pick up food from

choanocytes• Finish digestion• Take food to other cells

https://www.youtube.com/watch?v=m8a0oNsDEx8

Sponge Reproductiono Sponges are

hermaphrodites (produce both eggs & sperm)

o Sponges reproduce Sexually by releasing eggs & sperm into the water from the osculum

o Cross-fertilize each other’s eggs

o Form a larva that settles on a rock and grow into an adult sponge

Sponge releasing

eggs & sperm

Sponge Reproduction

oSponges can regenerate (regrow) lost body parts

oAlso reproduce asexually by budding and fragmentation (pieces break off & form a new sponge)

Surviving Harsh Conditions

o Gemmules are specialized buds made to survive harsh weather (hot or cold)

Write on the back of the graphic organizer

oContain food, amebocytes, and a protective covering of spicules

oReleased when a sponge dies

oBecome adult sponge once conditions become favorable