1 Sponge Body Structure 2 3 Spongin collagen

1

Sponge Body Structure 2

3

Spongin (collagen) 4

Choanocytes 5

Amoebocytes 6

Water Movement https: //www. youtube. com/ watch? v=p. TZ 211 c. Ij. X 8 7

Sponge Body Types • Simplest organization • Single cup • Choanocytes line cavity • Single opening at the top Why is their size limited? 8

Syconoid sponges • Tubular body - single opening at top • Body wall thicker and more complex • Outer openings lead to tubes that are lined with coanocytes • Central opening has no coanocytes 9

Leuconoid sponge Flagellated Chambers Leuconia 10

Poriferan reproduction Asexual: • Fragmentation – chunks of sponge break off • Budding – buds off the main spunge that have evolved to break off and start new sponge • Gemmule – internal bud produced by the sponge – – Amobeocytes condensed in Spicules middle and surrounded by spicules/sponges Common in freshwater sponges Amoebocytes 11

Sexual Reproduction Sponge Spawning • Most sponges are hermaphroditic (monecious) • Some species are oviparous – release sperm and eggs into water where they are fertilized • Most are viviparous – sponges retain the eggs, sperm is released, filtered, and fertilizes the internal eggs 12

Larvae • Once fully developed, sponges release a free-swimming larvae with flagella • Larvae swim around until they find a substrate, attach and develop into a young sponge 13

Harp Sponge (Chondrocladia lyra) 14

Eumetazoa: The Radiata • Distinct tissues • True body symmetry • No coelom 15

Body wall: Diploblastic 16

Phylum Cnidaria 17

Synapomorphies/Characteristics Polyp Medusa 18

Synapomorphies/Characteristics 19

Cnidocytes • How are sessile or slow-moving animals predatory? ? ? • All through a special cell called a cnidocyte • Spring-loaded trap that harpoons prey that touches the trigger on the outside Hydra nematocyst – This particular cnidocyte is called a cnematocyst • Types of organelles – – – Stinging (most common) Adhesive Grasping Lassos Springs http: //www. youtube. com/watch? v=PPYi. C 1 HDu-M http: //www. youtube. com/watch? v=6 z. Ji. Bc_N 1 Zk 20

Example of lasso cnidocytes 21

Nerve Net 22

Class Hydrozoa (hydroids) • • Polyp is the primary life-stage of this class Mostly marine, some freshwater 2700 species Some species like Obelia or Portuguese-mano-war form colonies https: //www. youtube. com/ watch? v=RBd. Cpcap. B 0 s 23

Hydrozoans http: //www. sciencemag. org/news/2016/03 /video-how-hydras-split-themselves-openeat 24

Class Scyphozoa • 200+ species • Marine only • There are some freshwater “jellies” but these are actually hydrazoans • Medusa is dominant form, polyp reduced or absent • Most are small (one at top right can have 70 m tenticles) • Very few deadly, often painful http: //www. youtube. com/watch? v =bcm. Lxs. J 5 SAg 25

Feeding/Reproduction • No active transport, prey digestion and energy diffuses to various body areas • Sexes are separate (typically) • Sperm is released into water, eggs retained by females • Horseshoe shaped areas inside most. Fish jellyfish are gonad tissue http: //www. youtube. com/watch? v =bcm. Lxs. J 5 SAg 26

Class Cubozoa • Box jellyfish • Umbrella is square shaped, one large tentacle comes off each corner of umbrella • Tropical and subtropical marine • Medusa dominant • Most venomous animal on planet – death as quickly as 4 minutes 27

Chironex fleckeri • • Most deadly box jelly Sea Wasp Tropical Australia Google “box jellyfish eyes” Swimming net to keep box jellies out 28

Class Anthozoa (corals, sea anemones) • • 6200 species All marine Polyp only, no medusa stage Body structure – see notes 29

Anemone Anatomy 30

Sea anemones pack many punches… http: //www. youtube. com/wa tch? v=r. Zt 7 ye. Tc 0_c Prey artificially wrapped with stained nematocysts Filaments with nematocysts Schlesinger et al. 2009. Proc. R. Soc. B 31

Corals • • Miniature anemones Colonial Secrete calcium carbonate See notes 32

Soft Corals • Coral that does not form calcium structure • horny coral, sea fans, sea pens, sea pansies, etc. • All colonial • Gastrovascular cavity of some species are interconnected and they can communicate 33

Zooxanthellae • Corals form symbiotic relationship with donoflagellates – zooxanthellae • Photosynthetic • Thrive in warm, clear, water • Increase productivity of water 34

Phylum Ctenophora (comb jellies) • Less than 100 sp. • Warm oceans • Eight rows of comblike cilia, beat in unison to propel animal • Two long tenticles called colloblasts – Secrete sticky substance for catching and holding small animals http: //www. youtube. com/watch? v=ic. KB 9 Ef. URh. Q 35