ANIMAL KINGDOM

INVERTEBRATE ANIMALS

Occupy all terrestrial and aquatic ecosystems

34 phyla

We will be studying:1. Sponges and Cnidarians2. Worms3. Molluscs4. Echinoderms5. Arthropods

INVERTEBRATE ANIMALS

1. SPONGES AND CNIDARIANS

SPONGES (PHYLUM PORIFERA)- Marine and freshwater- Asymetrical body plan- 2 cell layers, No tissues- Sessile- Trap food as water passes through internal body

channels

INVERTEBRATE ANIMALS

1. SPONGES AND CNIDARIANS

CNIDARIANS (PHYLUM CNIDARIA)- hydras, jellyfish, sea anemones, corals- Radial body symmetry- 2 cell layers specializing into tissues- Swim and capture prey using stinging tentacles

around the mouth- Food digested in gastrovascular cavity

INVERTEBRATE ANIMALS

1. SPONGES AND CNIDARIANS

CNIDARIANS (PHYLUM CNIDARIA)

INVERTEBRATE ANIMALS

1. SPONGES AND CNIDARIANS

CNIDARIANS (PHYLUM CNIDARIA)- 2 body formsa) Polyp: cylindrical, attaches to surfaces, extending tentacles

up and out, wait for preyEx: adult sea anemones, corals, hydras

b) Medusa: flattened, mouthdown form that is not attached, moves passively with currents or by body contractions

Ex: jellyfish

** May have one body form or alternate

INVERTEBRATE ANIMALS

1. SPONGES AND CNIDARIANS

CNIDARIANS (PHYLUM CNIDARIA)- 2 body forms

INVERTEBRATE ANIMALS

2. WORMS

FLATWORM (PHYLUM PLATYHELMINTHES)- Least complex- Acoelomates, 3 cell layers- Simple nervous system (brain-like density and

eyespot at head end)- Ex: parastic tapworms, flukes, free-living

planarians

INVERTEBRATE ANIMALS

2. WORMS

SEGMENTED WORMS (PHYLUM ANNELIDA)- Long tube-like bodies with ringed segments- Distinct head end- Several organ systems

INVERTEBRATE ANIMALS

3. MOLLUSCS (PHYLUM MOLLUSCA)

- Bilateral symmetry- Mantle, organ filled body, muscular foot, sense

organs- Coelom, 3 cell layers, 2 body openings- Soft body protected with hard shell- 3 classes

a) Class bivalviab) Class Gastropodac) Class Cephalopoda

INVERTEBRATE ANIMALS

3. MOLLUSCS (PHYLUM MOLLUSCA)a) Class bivalvia- Marine and freshwater- Clams, mussles, oysters, scallops- Protected by hinged shell

b) Class Gastropoda- Terrestrial, freshwater and marine- Shelled snails and non-shelled slugs- Coiled shell

INVERTEBRATE ANIMALS

3. MOLLUSCS (PHYLUM MOLLUSCA)

c) Class Cephalopoda- Octopus and squid- Marine- Grasping tentacles allow for propulsion

INVERTEBRATE ANIMALS

4. ECHINODERMS (PHYLUM ECHINODERMATA)

- Sea stars, sea urchins, sea cucumbers, sand dollars

- Marine animals- Radial symmetry- Spiny endoskeleton (internal skeleton of calcium

carbonate), covered in skin- Water vascular system including tube feet

INVERTEBRATE ANIMALS

5. ARTHROPODS (PHYLUM ARTHROPODA)

- Largest animal phylum- Spiders, scorpions, crustaceans, insects- Jointed foot- Exoskeleton (protein and chitin) which is

periodically shed