Invertebrates Classify living invertebrates into different phyla 2212021

Invertebrates Classify living invertebrates into different phyla 2/21/2021 1

Classification? Vertebrates • Animals with backbones • One phylum: chordates Animals • Animals without backbones • 8 phyla Invertebrates 2/21/2021 3

Invertebrate Phyla • • Sponges Cnidarians Platyhelminthes Nematodes Mollusks Annelids Echinoderms Arthropods 2/21/2021 Kingdom Phylum Class Order Family 4

Sponges (Porifera) • Most primitive • Cells relatively independent • Mostly marine • No Symmetry 2/21/2021 6

Cnidarians • Mostly marine • Radial Symmetry 2/21/2021 7

Cnidarians • Jellyfish • Hydra • Coral • Sea anemone • Portuguese Man-O-War 2/21/2021 8

Platyhelminthes • Flatworms • Bilateral symmetry • Cephalization 2/21/2021 9

Planarian – freshwater flatworm 2/21/2021 10

Nematods • Tube-like digestive tract • Roundworms! • Mouth and anus • No segmentation 2/21/2021 11

Mollusks • Clams, snails, squids • Varied habitats – Marine – Freshwater – Terretrial 2/21/2021 12

Annelids • Segmented worms • Common earthworm • Leech 2/21/2021 13

Echinoderms • Always marine • Starfishes, sea urchins, sea lilies • Spiny skin 2/21/2021 14

Brittle Star – An Echinoderm 2/21/2021 15

Arthropods • Joint-legged animals • External skeleton • Huge variation – mostly insects 2/21/2021 16

Section Review (cont. ) • • • 14 15 16 17 18 19 2/21/2021 invertebrates ectoderm sponges endoderm coelom Cnidarian • • • 20 21 22 23 24 25 segmented echinoderms Crustacea squirts 21

Invertebrates Classify living invertebrates into different phyla 2/21/2021 22