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Chapter 9 Porifera/Cnidaria Multicellular And Tissue Levels Of Organization Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Portuguese Man-Of-War (Physalia Physalis) Fig. 9.1 9-1 Photo © Diane Nelson Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Evolutionary Relationships of Poriferans Fig. 9.2 9-2 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hypothesis of Multicellularity Fig. 9.3 9-3 Porifera/Sponges * 550 million years old • means " pore bearing " * bodies are full of tiny pores and canals * filter feeding depends upon water currents thru their canals * bodies have: a gelatin matrix -- tiny spicules of Ca or Si a protein called spongin is in some * no true tissues or organs * aquatic sessile filter feeders as adults * mostly marine and colonial * many brightly colored * they provide a home for thousands of other organisms * can grow on many other living animals Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Simple Sponge Morphology Fig. 9.5 9-4 Form & Function = the numerous tiny body pores ( ostia ) are for incoming water = the big pores are ( oscula ) for water exhaust = openings lined with flagellated collar cells (choanocytes ) Function ? the flagellum create water currents through the sponge and filters microscopic food particles from the water = these cells also phagocytize (to eat) food Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sponge Body Forms Fig. 9.7 9-5 Types of Canal Systems 1. Asconoids: flagellated spongocoels (vaselike) simplest type, least common water enters thru a ostia then into the spongocoel outlet is 1 large osculum Ex: Leucosolenia (means white pipe - is a littoral marine tubular species) Asconoids cont. Types cont. . Syconoids: flagellated canals radial canals empty into a single osculum water enters thru incurrent canals flagella force water on thru internal pores or apopyles into the spongocoel and out via the osculum this type is in classes Calcarea and Hexactinellida Ex: Sycon (means a fig) Calcarea Types cont. . Leuconoids: flagellated chambers most common and complex, absence of spongocoel clusters of flagellated chambers filled with water from incurrent canals, ostia water is discharged into excurrent canals >>> several osculum form large colonies Leuconoids Types of cells sponge cells are loosely arranged in a gelatinous matrix ( mesohyl – jellylike layer , mesoglea) -- Pinacocytes--thin flat epithelial-type cells Function ? line -- Choanocytes--ovoid cells lining canals and chambers -- Mesenchyme--ameboid cells in the gelatin with phagocytic ability Functions ? may secrete spicules ( sclerocytes ) some secrete spongin fibers, collagen Slide 13 of 30 Types of skeletons 1. silicon spicules 2. crystalline calcium carbonate 3. a form of collagen called spongin • variations in spicules are used as classification keys Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sponge Larval Stages Fig. 9.8 9-6 Physiology of Sponges * life depends upon water flow * have millions of flagellated cells * mainly feed on bacteria, plankton and detritus * digestion is intracellular * diffusion and contractile vacuoles * may close oscula as a response Reproduction in Sponges both asexual and sexual asexually by budding and fragmentation - buds may be external or internal (gemmules) sexually thru being monoecious Meaning ? Sponges have great regeneration ability Sponge releasing gametes Class Calcarea Class Calcarea (Calcispongiae) = spicules of calcium carbonate = usually small sponges, often tubeshaped = all 3 canal types in this group = many drab but some bright yellow, green, red or lavender Ex: Leucosolenia (Scypha) , Sycon (Grantia) Grantia/calcarea whole cross section Calcarea/Grantia choanocytes (arrow) cross section, high power; Class Hexactinellida Class Hexactinellida (Hyalospongiae) Glass Sponges > nearly all deep-sea with vase / funnel bodies > skeleton forms a network Ex: Euplectella (Venus' Flower Basket ) Euplectella Class Demospongiae * 95 % of all species * are leuconoid and almost all marine * have silicon spicules if present, are bound by spongin Ex: freshwater -Spongilla and Myenia marine - Spongia and Hippospongia Hippospongia Class Sclerospongiae = small group which secretes a calcareous skeleton = called coralline ( coral like )sponges = leuconoid with silicon and spongin spicules possible = in cryptic locations Sclerospongia SOME THOUGHTS... Why are sponges important to other aquatic life ?_______________________ Why are sponges excellent pollution indicators ? _______________________ Do sponges still have an economic impact ? Many of these sponge-modified and spongeproduced chemicals have potent toxicity against human pathogens, cancer cells etc., or are useful against certain human ailments (e.g. antiinflammatory, cardiovascular, respiratory, analgesic etc. properties). _______________________ Of what value are sponges in research ? _______________________ Cnidarian Phylum CNIDARIA means “ nettle-like “ radial or bilateral symmetry diploblastic tissue level organization gelatinous mesoglea between epidermal and gastrodermis tissue layer gastrovascular cavity nervous system in form of nerve net there are types of nematocysts (stinging organelles) for defense, feeding and attachment Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cnidarian Body Wall Fig. 9.9 9-7 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cnidocyte Structure and Nematocyst Discharge Fig. 9.10 9-8 over 9K species has cells called cnidocytes with stinging organelles (nematocysts) characteristics group is also called Coelenterata ( meaning hollow gut ) almost all marine with many strange and lovely forms abundant in warmer shallow marine areas little economic importance except for reefbuilding some can inflict painful stings on humans Form and Function * polymorphism (many forms) or dimorphism (2 forms) * body forms are hydroid - a polyp (sessile & asexual) and the jellyfish form- medusa (freeswimming or floating & dioceous, sexually mature) * most polyps have a tube shape and the medusae an umbrella shape * Anthozoans (corals) are polyps and Scyphozoans (true jellyfish) are medusae * Hydrozoans usually go thru both forms during life Characteristics cont. Their are types of nematocysts (stinging organelles) for ______________________? Another feature is the Nerve Net or neuromuscular system Cnidarian nerve cells have been of interest to zoologists for many years because they may be the most primitive nervous elements in the animal kingdom. By studying these cells, zoologists may gain insight into the evolution of animal nervous systems. Class Hydrozoa meaning “ water animals “ 3 features that distinguish hydrozoans from other cnidarians 1. nematocysts are only in the epidermis 2. gametes are epidermal and released to the outside of the body rather than in the . gastrovascular cavity 3. the mesoglea never contains amoeboid mesenchyme cells How do medusas form? From a budding, a body wall of a polyp Hydra Hydra are named after the nine-headed sea snake of Greek mythology and are freshwater relatives of corals, sea anemones and jellyfish. All are members of a primitive phylum, the Cnidaria, and share in common stinging tentacles and a radially symmetrical body plan Hydra bear the name of the Greek mythological creature of Lerna, described as having the body of a hound and 100 serpentine heads, each bearing poisonous breath. With so hideous a visage that many died of fear just viewing the mythological beast, the freshwater hydra has much legend to live up to. Hercules vs the Hydra - YouTube HYDRA LERNAIA was a gigantic, nine-headed water SERPENT, who grew two heads in place of each that was decapitated. She was slain by Herakles who applied a burning brand to the stumps. The gods then placed her in the heavens as the Constellation Hydra. Hydra cont. in freshwater as a solitary polyp prefers underside of vegetation in clean water tiny but visible to the eye moves by gliding on its basal disc, inch worming or somersaulting eats water fleas, insect larvae and worms shoots prey with nematocysts reproduces both asexually (buds) and sexually (dioecious) statocysts – an organ of equilibrium and balance in many invertebrates. Hydra cont. The more common Hydroids would be Obelia with its dimorphism, The freshwater medusa Craspedacusta sowerbyi and the specialized member gonozooid – reproductive polyp that produces medusae by budding Hydra feeding - YouTube Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Obelia Structure and Life Cycle Fig. 9.12 9-10 Polyp, Hydranth, Gonangium, Medusa Definitions pol·yp A coelenterate, such as a hydra or coral, having a cylindrical body and an oral opening usually surrounded by tentacles. hy·dranth A feeding zooid in a hydroid colony having an oral opening surrounded by tentacles. Gonangium A capsule developed on certain hydroids inclosing the blastostyle upon which the medusoid buds or gonophores are developed; me·du·sa The tentacled, usually bell-shaped, freeswimming sexual stage in the life cycle of a coelenterate, such as a jellyfish. Portuguese man of war Physalia (means bladder) called the Portuguese man-of-War is a huge colorful floating medusa of the tropics can inflict painful stings lacks swimming capabilities Portugese Manowar - YouTube Portuguese man of war Class Scyphozoa means " cup animals " dominate life cycle is the medusae some are huge six footers like Cyanea (means darkblue) most harmless some still can deliver painful stings Aurelia Rhopaliulm – sensory structures Planula develops into poly called scyphistoma which live 1-2 years. Budding produces minature medusae called ephyrae Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Aurelia Life History Fig. 9.16 9-13 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Structure of Scyphozoan Medusa Fig. 9.15 9-12 Source: After L. H. Hyman, Biology of the Invertebrates, Copyright © 1940 McGraw-Hill Publishing Co. characteristics Scyphozoans share a number of attributes with other cnidarians: (1) they typically possess tentacles, (2) their symmetry is radial, (3) the body wall consists of an outer epidermis and inner gastrodermis, separated by a layer of jelly-like mesoglea, (4) the mouth is the only opening to the digestive system, (5) nematocysts or "stinging capsules", formed by specialized cells called nematocytes, are present. The medusae of Scyphozoa are unique in being typically much larger and anatomically more developed than the polyp. moon jelly Aurelia aurita Reproductive pics. of aurelia Aurelia scyphistoma Aurelia early strobila Reproduction cont. Aurelia late strobila Aurelia ephyra Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Generalized Cnidarian Life Cycle Fig. 9.11 9-9 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Structure of Gonionemus Medusa Fig. 9.13b 9-11 Anatomy 1. Manubrium 2. Gonads 3. Tentacles 4. Radial canal 5. Circular (ring) canal 6. Statocyst Class Cubozoa means " cube animals " = are similar = strong swimmers that eat fish = Example: Tripedalia cystophora (3 rudder) = a dangerous member is Chironex (sea wasp) which has a sting that can kill a human in 20 minutes Video: Deadly Sea Wasp Cubozoa Pictures Chironex fleckeri – Sea Wasp Cubozoa – sea wasp It is a jellyfish (Chironex fleckeri). The "bell" of this box jelly can get as big as a basketball with up to 60 tentacles hanging down as long as 15 feet, which is pretty good sized jelly. Not as big as the world-record jellyfish, though Not everyone who has been stung by a Sea Wasp has died, but those who didn't may have wished they had. The sting from a box jelly is said to be excruciatingly painful. It can cause nausea, vomiting and breathing problems. The Aussies have developed an antivenom (something to counteract the toxic effects of the jelly's venom). Doesn't do you a lot of good if you got stung so badly while you were out in the water and then couldn't even make it back to shore. But, you really need to get tangled up good (contacting at least 10 feet of tentacle) in order to experience its ultimate effect - death. Sea wasp cont. Location: Off the north coast of australia, and in the waters off southeast asia. Stats: The venom from a single creature can kill up to 60 adults. Get stung by one and you have anywhere from 30 seconds to four minutes to get help or die! Class Anthozoa means " flower animals " always polyps, colonial or solitary, no medusae stage, found in all depths and in all oceans anthozoa differ from hydrozoans in 3 ways. 1. the mouth of an anthozoan leads to the pharynx 2. mesenteries (membranes) that bear cnidocytes and gonads on their free edges divide the gastrovascular cavity into sections 3. the mesoglea contains amoeboid mesenchyme cells 3 classes sea anemones - outside radial inside biradial symmetry - solitary frequently large - siphonoglyph – ciliated tract that moves water into the gastrovascular cavity - glides on pedal disc, crawls on side, walks on tentacles, some float by using a gas bubble - feed on invertebrates or fish - asexual – regeneration, budding---- sexualmonoecious ( self fertilization does not occur sperm and egg develop at different times is known as protandry) or dioecious Video -- Clownfish and Sea Anemone Partnership -National Geographic Pictures of Sea Anenomes Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Structure of an Anemone Fig. 9.19 9-14 Charles Lytle and J. E. Wodsedalek, General Zoology Laboratory Guide, 11 th Hill. Reprinted by permission of The McGraw-Hill Companies. ed., Complete Version, New York, McGraw- 2 other classes of Anthozoa Corals – stony corals same as sea anemones but lack siphonoglyphs reproduce same as anenomes Octacorallian- warm water 8 featherlike tentacles, create the gardens of a coral reef Ex: Renilla (sea pansy) Ptilosarcus (sea pen) Gorgonia (sea fan) Corals Octacorallian Pictures Coral Reefs Very productive ecosystems with a great diversity of life hermatypic (reef-building) and coralline algae are the major players as many as 300 common fish species can inhabit a reef the ecosystem is very efficient at recycling Why are reefs so very important ?? (at least 3 reasons) What is destroying the reefs? (at least 7) corals Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Longitudinal Section of a Stony Coral Polyp Fig. 9.20 9-15 Phylum CTENOPHORA means " comb bearing " * marine, less than 100 species; almost all freeswimming *spherical form but some are flattened and/or elongated * colloblasts – adhesive structures *2 small anal canals *monecious * 8 rows of comblike plates for motion * commonly called " sea walnuts " or " comb jellies " * only 1 species has nematocysts * weak swimmers but easily seen due to bioluminesce Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ctenophore Mnemiopsis Fig. 9.22 9-16 Class Tentaculata has the example-- Pleurobrachia it looks like an egg with 2 long tentacles All in this class have two tentacles; a characteristic species is Hormimorpha plumosa seen right. Some in this class are flattened into a ribbon-like shape along the plane of the tentacles and have an undulatory (To cause to move in a smooth wavelike motion. To give a wavelike appearance or form to.) motion. Other Ctenophores are Beroe which is pink and conical Cestum called Venus' Girdle Mnemiopsis along the Gulf Coast Ctenophores Class Tentaculata Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cladogram of Cnidarian Taxonomy Fig. 9.23 9-17 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Coral Reef Ecosystem Page 139 9-18 Photo © McGraw-Hill Higher Education, Barry Barker, Photographer Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Coral Bleaching Page 139 9-19 Photo © Diane Nelson • Man-Of-War Jellyfish • The Portuguese Man-of-War, or Physalia physalis ( in Greek this means air bubble ) is most often thought of as a jellyfish but in fact it is not in the true jellyfish at all. It belongs in the family of Hydrozoans. • Another common error is that that it is thought to be a single organism. The truth is that a Man-Of-War consists of four different organisms. • Pneumatophore - This is the gas filled float, or baloon looking portion, that glides on the surface of the water. It is a modified version of a polyp and is inflated with a carbon monoxide gas. • Dactylozooids - These are the tenticles that extend down below the float. They are the mechanism that catches, stings, and brings its food to the feeding organism. • Gastrozooids - This is the 'digestive' organism. Think of it as an elongated, external, hollow mouth that extends itself to encompass the food item. • Gonozooids - These are the reproductive organisms. • For as feared as the Man-Of-War is, especially by other fishes, there is one fish ( Nomeus sp.) that is immune to the stinging tenticles. This fish spends most of its time amougst these tenticles either for protection, or possibly as a decoy to lure in other fishes. • Bizarre creatures