Overview Life Without a Backbone Ch 33 Lecture

Overview: Life Without a Backbone Ch. 33 Lecture Objectives 1. Define Invertebrates 2. Phylum Porifera 3. Phylum Cnidaria

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Phylum Porifera “pore bearer” (the sponges) Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Choanocyte Osculum Flagellum Collar Food particles in mucus Choanocyte Azure vase sponge (Callyspongia plicifera) Spongocoel Phagocytosis of food particles Amoebocyte * Suspension Feeders Pore Epidermis Spicules Water flow Amoebocytes Mesohyl Fig. 33 -4 Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Sponge Spicules – Calcium Carbonate OR Silica Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Sponge Body Types Asconoid Syconoid Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings Leuconoid

Reproduction Asexual Reproduction • Budding via gemmules Sexual Reproduction • Hermaphroditic with planula Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

https: //www. youtube. com/watch? v=8 ue. Kl. Shb 9 Ls Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Phylum Cnidaria Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Polyp Mouth/anus Tentacle Medusa Gastrovascular cavity Gastrodermis Body stalk Mesoglea Epidermis Tentacle Mouth/anus Fig. 33 -5 Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Tentacle Cuticle of prey Thread Nematocyst “Trigger” Thread discharges Cnidocyte Thread (coiled) Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings Figure 33. 6

Two Clades for Phylum Cnidaria (b) Clade Medusozoa (c) Clade Medusozoa - the scyphozoans - the Cubozoans (d) Clade Anthozoa - sea anemone & coral (a) Clade Medusozoa -the hydrozoans Fig. 33 -7 Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Clade Medusozoa – the hydrozoans: Hydra sp. (not colonial – polyp dominant) Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Lifecycle: Clade Medusozoa, a hydrozoan Obelia sp. (polyp dominant) Feeding polyp Reproductive polyp Medusa bud ASEXUAL REPRODUCTION (BUDDING) Portion of a colony of polyps Haploid (n) Diploid (2 n) Gonad Medusa Egg SEXUAL REPRODUCTION Sperm FERTILIZATION Zygote 1 mm Key MEIOSIS Developing polyp Planula (larva) Mature polyp Fig. 33. 8 Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Clade Medusozoa, a scyphozoan (true jelly, medusa dominant): Aurelia sp. Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Lion’s mane jelly – 7 ft across & 120’ long w/ 8 sets of tentacles (stung 50 people simultaneously) https: //www. youtube. com/watch? v=Z 7 d 5 P 0 p. DVUo Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Clade Anthozoa: sea anemone life cycle (no medusa stage) Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Solitary Anemone in California tide pool Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings

Clade Anthozoa: a coral with symbiotic algae Copyright © 2008 Pearson Education, Inc. , publishing as Pearson Benjamin Cummings