Evaluate the limit or show that it does not exist.
Acoelomate Worms But first, some review... Kingdom Animalia Phylum Cnidaria Class Anthozoa Dominant stage How many germ layers Polyp 2 – ectodermis and Obelia polyp What is B Gonangium What are the structures in B Medusa buds What is C Hydranth Phylum Porifera Organization/Body type A Asconoid B What is A Osculum C What is B Choanocyte D What is C Spongocoel E What is D Ostium (plural ostia) What is E Amoebocyte This Lab = Acoelomate Worms s n m a t Phylum Platyhelminthes z o s t Phylum Phylum Class Class Class Class Other d u Cnidaria Nemertea Cestoda Monogenea Trematoda Turbellaria Lophotrochozoans E D Note: this is very simplified. Many taxa not included. • General – Platyhelminthes (platy=flat,-helminth=worm) • Level of Organization: Organ • Acoelomate (a- = ‘not’ or ‘without’) – Triploblastic (3 tissue layers) • Ectoderm • Mesoderm • Endoderm • Symmetry: bilateral – Dorsoventrally flat • Digestion – Incomplete: mouth, pharynx, intestine • (no anus) – Feeding tools (flukes): oral and ventral suckers for attachmentwhile feeding • Circulation: none • Respiration – Via diffusion through cell membrane • Excretion – Flame bulbs – flagellatedand flicker like a flame, which draws wastes through system of excretory canals and eventually exits the body. • Nervous System – Exhibit cephalization – a concentrationof nerve tissue at the anterior ‘head’ region – Ladder type nerve system running length of body – Ocelli (flatworms) - light-sensitive eyespots – Tactile and chemoreceptive cells located all over the body to sense water current and direction • Support – Hydrostatic skeleton • Locomotion – Because a mesoderm is present, there are more complex muscles: longitudinal, circular and diagonal – Allows for a variety of movements: gliding, crawling, and a rhythmic wave-like motion Circular Longitudinal Dorsoventral • Reproduction – Monoecious (one house) – both male and female sex organs in one body – Some spp. have separate male/female individuals (dioecious) and some have asexual stages. • Ecology – Live in water, moist soil, terrestrial Taxonomy • Acoelomate condition not monophyletic • Kingdom Animalia – Phylum Platyhelminthes • Class Turbellaria • Class Trematoda • Class Cestoda – Phylum Nemertea • Class Turbellaria – mostly free living – ciliated epidermis – Most are harmless – ex. Planaria, & colorful marine species • Class Trematoda – flukes – all parasitic (have suckers and hooks for attachment and feeding) – leaflike or cylindrical in shape – No sensory structures – Monoecious (one individual has both male and female reproductive structures) to allow for reproductionwhen invading a new host – complex life cycles (2+ hosts) – 1st host – mollusks (snail) – asexual reprod. – 2nd host – usually vertebrate – sexual reprod. – ex. Schistosoma Liver fluke of deer • Class Cestoda – tapeworms – scolex (head) with suckers and hooks for attachment – parasitic in digestive tract of vertebrates – feed by absorption from host’s digestive contents – long ribbon-like body divided into a series of proglottids • Class Cestoda – tapeworms a.) immature proglottids – lack mature reproductive organs, found anterior. b.) mature proglottids – male and female organs present and genital pore visible. c.) gravid proglottids – full of eggs, found posterior. ex.: Beef and Pork Tapeworms • Phylum Nemertea – 1000 species of predatory ribbon worms – tube-like proboscis can be everted to catch prey (above) – Transitional between flatworms and mollusks • Body similar to Turbellarians in that they have a ciliated epidermis, circular and longitudinal muscles and similar excretory structures. • Possess a complete digestive system(mouth, intestine, and anus) and their larvae resembles those of mollusks. This Lab • Live specimens: Planaria • Preserved slides: Planaria whole mount and cross section; fluke whole mount, tapeworm whole mount • Preserved specimens: various Trematoda, Turbellaria, Cestoda and Nemertea specimens To what phylum do these organisms belong To what class do these organisms belong What kind of symmetry do these organisms exhibit Name the sensory organs found on these organisms. What type of muscles are found in 1, 2 and 3 Does this organism show signs of a body cavity What are the three germ layers found in this organism Where is the pharynx Where is the intestine Oral sucker A Intestines B C Uterus D Yolk glands Testes E To what phylum do these organisms belong To what class do these organisms belong Name the lettered structures. Is this organism monoecious or dioecious To what phylum do these organisms belong To what class do these organisms belong What hosts are involved in this life cycle Name this structure. Each segment is called what These organisms are all ribbon worms. To what phylum do these organisms belong How are these organisms different from flatworms Lophotrochozoans This Lab = Other Small Lophotrochozoans Acoelomate Phylum Phylum Phylum Phylum Molluscs & worms AcanthocephalaRotifera GastrotrichaEctoprocta Annelids Ecdysozoans Deuterostomes – Either have Lophophore – ciliated crown of tentacles – OR Trochophore larvae - ring of cilia for swimming – OR included because of genetic data – Level of Organization: Organ-system – Triploblastic (3 tissue layers) – Acoelomate, Psuedocoelomateor Coelomate Ectoderm Mesoderm Pseudocoel Endoderm • Symmetry: bilateral • Digestion – Incomplete: mouth, pharynx, intestine (no anus) – Complete: mouth, pharynx, intestine, and anus – Feeding tools: complex jaws made up cuticle, lophophores • Ecology – 16 Phyla- many lifestyles – Marine and freshwater – Filter feeders, predatory, or parasitic – Parthenogenic (Gastrotrichs, Rotifers) Lophotrochozoan Taxonomy • Kingdom Animalia • Clade Lophotrochozoa – Phylum Gastrotricha – Phylum Rotifera – Phylum Ectoprocta (Bryozoa) – Phylum Acanthocephala Phylum Gastrotricha • Acoelomate • Complete digestive system • Filter feeders – microalgae, bacteria, small protozoans • Hermaphroditic/parthenogenic • Presence of duo-adhesive glands on the foot Phylum Rotifera • Pseudocoelomate • Complete digestive system • Fresh water, damp soil, marine • 3 Classes Nebalia – Seisonidea: Only 3 described species • Dioecious. Lives on gills of Nebalia – Monogononta: Complex lifecycle involving amictic and mictic females – Bdelloidea: Parthenogenetic lifecycle; undergo cryptobiosisto withstand freezing and drying Rotifera Life Cycle Phylum Ectoprocta • Marine and freshwater • Also called Bryozoans • Coelomate, complete digestive system • Filter feeders • Hermaphroditic Phylum Acanthocephala 1,100 species Proboscis: (tongue-like mouth part) includes rows of recurved spines used for attachment to a host Endoparasitic : no digestive tract. They absorb all nutrients directly from the digestive tract of their host - Pseudocoelomate - Closely related to Rotifers This Lab • Live specimens: Lepidodermella, Monostyla, Philodina • Preserved slides: Rotifers and Ectoprocts • Preserved specimens: Acanthocephala specimens Name the 4Lophotrochozoan phyla we covered today. Gastrotricha, Rotifera, Ectoprocta, Acanthocephala Do Rotifers have a true coelom NO: They arepseudocoelomate What about members of the phylum Gastrotrichia NO: They areacoelomate How many tissue layers do Lophotrochozoans have All are triploblastic (three germ layers) What are the two defining characteristics for the group Lophotrochozoa Lophophore – a ciliated crown oftentacles OR Trochophorelarvae – a ciliated crown of tentacles Do the lophotrochozoans exhibit protostome or deuterostome development Protostome Which other phyla covered this week exhibit protostome development Platyhelminthes and Nemertea To what Phylum does this lophotrochozoan belong Gastrotricha What is the phylumand howdoes this animal feed Acanthocephala Spiny-headed worms are endoparasites Review - last lab What phylum do tapeworms belong to Platyhelminthes What class do tapeworms belong to Cestoda Why do we say Platyhelminthes have an incomplete digestive system They do nothave an anus What phylum do ribbon worms belong to Nemertea What is this structure What are these “segments” called Proglottids Scolex Introductiontothe AnimalKingdom Whatareanimals • Multicellular • Heterotrophic • Lackcellwall • Respondtoenvironment • MembersofKingdomAnimalia Animals:BodyPlansandClassification • Germ(PrimaryTissue)Layers • BodyCavity(notveryusefulforphylogeny) • SkeletalSystem • Symmetry • LevelofOrganization Cranial Orientation (Anterior) Howdowedescribethe locationofpartsonan animal’sbody Proximal Median Lateral Ventral Aboral Distal Caudal Oral Levels of Organization • Cell: specialized cell types, but no tissues. • Tissue level: specialized tissue types, but no organs. • Tissue-Organ: organs made up of 2 or more tissues. • Organ-system level: organs functioningtogether. GermLayers NoTissueLayers Particularcelltypesarrangedinlayers indevelopingembryo Ectoderm -outerlayerà nervoussystem, nails,hair,epidermallayerofskin Mesoderm-middlelayerà circulatory system,reproductivesystem,muscle,bone, dermis,kidneys Diploblastic Endoderm - innerlayerà liningof - Ectoderm digestivetract,liningofurinarybladder, - Endoderm lungs,liver,pancreas Endoderm Ectoderm Triploblastic: all 3 tissue layers Mesoderm BodyCavity 3types (triploblasts only) cavity that separates the gut from the body wall. • Separates organs • Helps coordinate movement • Isolates injuries Main difference between body cavity types is in how the mesoderm is arranged! Skeleton Hydrostatic Skeleton Endoskeleton Exoskeleton Symmetry Asymmetry Radial Bilateral Sensory System - Allows an organism to react to, and interact with, its environment. Water Conservation Organisms that live on land have evolved structures to prevent water loss. - Cuticle - Exoskeleton/scales - Behavioral adaptations Symmetry Bilateral Diploblastic Triploblastic Mix of body cavities! No tissues ThisLab • Examinespecimensaroundtheroom • Besuretounderstandthefollowing: – Orientation – GermLayers – BodyCavity – Symmetry – OrganizationLevel – TypeofSkeleton – AdaptationsforWaterConservation Cavitytype Acoelomate – no body cavity Cavitytype Coelomate – true body cavity Cavitytype Pseudocoelomate– false body cavity BodySymmetry Asymmetry Radial Bilateral SkeletonTypes Endoskeleton Hydrostatic Exoskeleton AdaptationsforWaterConservation • Reptile – Integumentwithscales,behavior • Insect – Integumentwithwaxycovering • Earthworm – Integumentreducesevaporation,behavior • Frog – Behavioral (seekmoistenvironments,reducesurfacearea) • Mouse – Integumentreducesevaporation,behavior Annelidaand Nematoda This Lab = More Worms Phylum Annelida Other Class Class Class Phylum Lophotrochozoans Polychaeta Oligochaeta Hirudinea Nematoda Panarthropoda Deuterostomes Ecdysozoans • PhylumAnnelida – segmented(metameric)worms • Septadividesegments – firsttodeveloppairedappendages • LevelofOrganization:Organ -System – Triploblastic – Coelomate • Symmetry:bilateral • Digestion:Complete – Mouth,intestine,anus – specializedstructures:suckers,crop,gizzard • Circulation – closed,withmultiple“hearts”topumpblood • Respiration – throughskin,gills,orparapodia • Excretion – nephridia • NervousSystem – CerebralGanglia+VentralNerveChord • Support – circularandlongitudinalmuscles – Hydrostaticskeleton • Locomotion – setae • Reproduction – MonoeciousorDioecious – Clitellum – cocoonproducing • Ecology – Aquatic:freshormarine.Terrestrialformsneed moisturetorespire.Someareparasitic. • Taxonomy – PhylumAnnelida • ClassPolychaeta • ClassOligochaeta • ClassHirudinea ClassPolychaeta:“manysetae” • parapodia (pairedfeet)bearinm anyseta, • manysegments • noclitellum • welldevelopedhead • alldioecious • mostlymarine;10,000species • Ex.:clamworms ClassOligochaeta: “fewsetae” • clitellum presentinadultforms • noparapodia,fewsetae • manysegments • poorlydevelopedhead • terrestrialandfreshwater • Ex.:earthworms ClassHirudinea • clitellumpresentduring reproduction • fewersegments • anteriorandposterior suckers • nosetaeorparapodia • terrestrial,freshwater andmarine • Ex.:leeches Taxonomy Hookworm • PhylumNematoda – Includesroundworm, heartworm,hookworms, trichinaworms,pinworms Caenorhabditiselegans Heartworm Pinworm Nematodes: • LevelofOrganization:Organ -System • Symmetry:Bilateral • CompleteDigestiveSystem • Nocirculatory/respiratorysystem • Pseudocoelomate(pseudo=‘false’)fluid-filledspace withorgans • Hydrostaticskeleton • Cuticle:anon-cellular,flexiblecoveringover ectodermmadeofprotein • Dioecious EarthwormDissection AscarisDissection ThisLab • Viewpreservedspecimens • EarthwormDissection • NematodeDissection(female) • BeabletotellmaleandfemAscaris apart To what class does this organism belong POLYCHAETA How can you tell PARAPODIA What is the importance of setae LOCOMOTION To what phylum does this organism belong ANNELIDA Acoelomate, psuedocoelomate or coelomate COELOMATE To what class does this organism belong OLIGOCHAETA How can you tell CLITELUM, NO PARAPODIA, REDUCED SETAE The repeated segments found in all Annelida organisms is called what METAMERISM Open or closed circulatory system CLOSED 1. Pharynx 2. Esophagus 3. Ovary 4. Crop 5. Intestine 6. Nephridia 7. Dorsal blood vessel 8. Septa 9. Gizzard 10. Seminal vesicles 11. Seminal receptacles Dorsal blood vessel Intestinal epithelium (endoderm) Lumen of intestine (intestinal cavity) Circular muscles Longitudinal muscles Epidermis Ventral blood vessel Coelom Ventral nerve cord To what class does this organism belong HIRUDINEA What are the functions of the suckers LOCOMOTION, FEEDING Wrap-Up - Ascaris Cuticle Ascaris Dissection Oviduct Annelidaand Nematoda This Lab = More Worms PhylumAnnelida OtherLophotrochozoansClass Class Class Phylum Polychaeta Oligochaeta Hirudinea Nematoda Panarthropoda Deuterostomes Ecdysozoans • PhylumAnnelida – segmented(metameric)worms • Septadividesegments – firsttodevelop airedappendages – Closedcirculatorysystem • LevelofOrganization:Organ-System – Triploblastic (ectoderm,mesoderm,andendoderm) – Coelomate • Symmetry:bilateral • Digestion:Complete – Mouth,intestine,anus – specializedstructures:suckers,crop,gizzard • Circulation – closed,withmultiple“hearts”topumpblood • Respiration – throughskin,gills,orparapodia • Excretion – nephridia • NervousSystem – CerebralGanglia+VentralNerveChord • Support – circularandlongitudinalmuscles – Hydrostaticskeleton • Locomotion – setae • Reproduction – MonoeciousorDioecious – Clitellum – cocoonproducing • Ecology – Aquatic:freshwaterormarine.Terrestrialforms needmoisturetorespire.Someareparasitic. • Taxonomy – PhylumAnnelida • ClassPolychaeta • ClassOligochaeta • ClassHirudinea ClassPolychaeta:“manysetae” • parapodia (pairedfeet)bearingmanysetae • manysegments • no clitellum • welldevelopedhead • alldioecious • mostlymarine;10,000species • Ex.:clamworms ClassOligochaeta: “fewsetae” • clitellum permanent • noparapodia,fewsetae • manysegments • poorlydevelopedhead • terrestrialandfreshwater • Ex.:earthworms ClassHirudinea • clitellumpresentduring reproduction (maturation) • fewersegments • anteriorandposterior suckers • nosetaeorparapodia • terrestrial,freshwater andmarine • Ex.:leeches PhylumNematoda Hookworm – Includesroundworm, heartworm,hookworms, trichinaworms,pinworms Caenorhabditiselegans Heartworm Pinworm Nematodes: • LevelofOrganization:Organ -System • Symmetry:Bilateral • CompleteDigestiveSystem • Nocirculatory/respiratorysystem • Pseudocoelomate(pseudo=‘false’)fluid-filledspace withorgans • Hydrostaticskeleton • Cuticle:anon-cellular,flexiblecoveringover ectodermmadeofprotein • Dioecious ThisLab • Viewpreservedspecimens • EarthwormDissection • NematodeDissection(female) • BeabletotellmaleandfemAscaris apart Earthworm Dissection Ascaris Dissection Dorsal blood 1 vessel 2 Intestinal epithelium 3 (endoderm) Lumen of intestine (intestinal cavity) 4 Circular muscles 5 Longitudinal muscles 6 Epidermis 7 9 Ventral blood vessel Coelom 8 Ventral nerve cord Mollusca • Phylum Mollusca – Includes chitons, snails, slugs, oysters, squids, octopus,and cuttlefish – 90,000 living species; 70,000 fossil species – Molluscus is Latin for ‘soft’ Flatworms & This Lab = Phylum Mollusca other small Class Class Class Class Lophotrochozoans Polyplacophora Gastropoda Cephalopoda Bivalvia Annelids Ecdysozoans Deuterostomes Protostomes- Lophotrochozoans This Lab = Phylum Mollusca Flatworms & other small Class Class Class Class Lophotrochozoans Polyplacophora Gastropoda Cephalopoda Bivalvia Annelids Ecdysozoans Deuterostomes mollusk trochophore larvae • Level of Organization: Organ-system – triploblastic – three tissue layers (ectoderm, mesoderm, and endoderm) – Coelomate – true body cavity, lined fully by mesoderm Ectoderm Mesoderm Coelom Endoderm • Symmetry - bilateral • Digestion – Radula – scraping organ, tongue-like, for feeding Radula of a snail • Circulation – Open Circulatory System – with heart. • “Open” = blood is not contained in vessels (i.e., veins and arteries), but is loose in sinuses. • Exceptions: Squid and Octopus have a closed circulatory system. Open Closed gills • Respiration – by gills, mantle, lung or body surface (diffusion) – Those on land (snails and slugs) have lost their gills and respire by means of a mantle vascularized mantle wall, which has become modified to function as a primitive lung • Excretion – saclike kidneys take waste from blood (metanephridia ) • Nervous System – cephalization – Nerve-ring at head and nerve cords running longitudinally. – Some sense organs (eyes) • Support – external dorsal shell, secreted by the mantle – Exceptions: some molluscs lack a shell (squid, octopus, and slugs) • Locomotion – by muscular foot (snails) or modified tentacles (squid and octopus) • Reproduction – Monoecious (both male and female organs in one individual) or Dioecious(separate sexes) – Internal fertilization in squid, and some slugs/snails and clams • Ecology – Freshwater, marine water, and land – Filter feeders, grazers, carnivores • Taxonomy – Phylum Mollusca • Class Polyplacophora • Class Gastropoda • Class Bivalvia • Class Cephalopoda Class Polyplacophora (“bearing many plates”) – elongated,dorsally flattened body – radula present – shell of eight dorsal plates – foot broad and flat – ex.: chitons Class Bivalvia (“two halves”) – two shells/valves hinged – most are sessile filter feeders – mantle on each valve – sheath of skin secretes shell – ex.: clams, mussels, and oysters – http://www.youtube.com/watch v=I0YTBj0WHkU – Gills covered in cilia and are adaptedprimarily for filter feeding, but they are highly vascularized and also are efficient for gas exchange Class Gastropoda(“stomach foot”) – radula on well developedhead – large flat foot – shell, usually coiled, many species exhibit torsion – ex.: snails, slugs, and conches Class Cephalopoda(“head foot”) – shell reduced or lost – tentacles rather than foot – well-developed head with eyes – ex.: squid, octopus, Nautilus Octopus camouflaged: http://www.youtube.com/watchv=GRSbC6HAgNE Octopus with coconut: http://www.youtube.com/watchv=RUN6c5yWJhQ Cuttlefish hunting: http://www.youtube.com/watchv=W1gTSQPXZas Radula Wrap-Up What Class Cephalopoda Polyplacophora Bivalvia Gastropoda Squid External Structures Fin Mantel Collar Online Help (Squid Anatomy) • http://www.youtube.com/watchv=OueQ9k U36i0 Porifera and Cnidaria Porifera • Taxonomy – Kingdom Animalia • Phylum Porifera This Lab = Phylum Porifera Kingdom Class Class Class Animals with Fungi Choanoflagellates Hexactinellida Demospongiae Calcarea Placozoa distinct tissues Osculum Porifera (opening on the ‘top’ of water exits)here Porifera = ‘pore -bearing’ – water flows through numerous tiny holes in their ‘body’ General body plan: Ostium (openings in side of sponge where water enters) http://www.youtube.com/watchv=bf0CoQSpongocoel (empty center of sponge) Porifera • 3 body arrangements dependingon the amount of branching between ostia and spongocoel: Asconoid Syconoid Leuconoid Spongocoel Spongocoel & Oscula & only radial canals multiple canals Porifera • Level of Organization – Cellular – Three types of specialized cells: Choanocytes – have flagella, responsible for obtaining food Pinacocytes – line surfaces Amoebocytes – in interior of sponge, digest food, secrete spicules, aid in reproduction, etc. Porifera • Symmetry: Asymmetric • Digestion: phagocytosis and amoebocytes • Circulation: None • Respiration & Excretion: Via diffusion • Nervous System: None • Locomotion: None Porifera Support – Spicules (hard, glass-like) – Spongin (soft) Reproduction Sexual – via eggs & sperm Asexual – via budding or regeneration This Lab = Phylum Cnidaria Phylum Class Class Class Class Class Bilateral Porifera Hydrozoa Cubozoa Scyphozoa Staurozoa Anthozoa animals Placozoa Cnidaria • Level of Organization: Tissue – Diploblastic = two germ layers 1. Epidermis – outside 2. Gastrodermis (endodermis) – inside – Mesoglea = noncellular, gelatin layer • Two body forms (some species alternate between both) – Polyp (Anthozoa, Hydrozoa) • Like an anemone, ‘mouth’ opens dorsally • Benthic (bottom-dwelling) – Medusa (Scyphozoa) • Like a jellyfish, ‘mouth’ opens ventrally • Pelagic (open ocean) Cnidaria Cnidaria Digestion – Feeding done using nematocysts (specialized structure) within cnidocyte (specialized cell) – Figure shows cnidocyte before and after firing Cnidaria • Symmetry: Radial • Circulation: None • Respiration & Excretion: Via diffusion • Nervous System: Simple nerve net • Support – Hydrostatic-like skeleton – Calcium carbonate (corals) • Locomotion – Simple muscle contraction (jellyfish contract not to move, but to bring food closer to their tentacles!) Cnidaria Reproduction Asexual, via budding Sexual – polyp and medusa stages Both Cnidaria • Taxonomy – Phylum Cnidaria classification depends on whether the medusa or polyp stage is dominant in life cycle – Class Hydrozoa • Polyp stage is dominant • Example: Hydra, Obelia, Man o’ War – Class Scyphozoa • Medusa stage dominant • Example: jellyfish – Class Anthozoa • Polyp stage ONLY • Example: corals and sea anemones Cnidaria • Taxonomy – Phylum Cnidaria classification depends on whether the medusa or polyp stage is dominant in life cycle Class Hydrozoa • Polyp stage is dominant • Example: Hydra, Obelia, Man o’ War Class Scyphozoa • Medusa stage dominant • Example: jellyfish Class Anthozoa • Polyp stage ONLY • Example: corals and sea anemones This Lab • Examine Porifera and Cnidaria specimens • Understand the flow of water through a sponge • Understand the structure and function of the cnidocyte and nematocyst Wrap-Up 1. What phylum are sponges in PORIFERA 2. How do sponges reproduce SEXUAL AND ASEXUAL 3. What is this hole OSCULUM 4. Through what structures and in what order does water flow thrua sponge OSTIA, SPONGOCOEL, OSCULUM 5. What is the function of spicules and sponginSUPPORT What is this cell CNIDOCYTE What is this organelle NEMATOCYST What does it do CAPTURE PREY Class Anthozoa Class Scyphozoa Example: corals and sea anemones Example: jellyfish Class Hydrozoa Which class do these examples belong to Example: Hydra, Obelia, Man o’ War Do all these have both a polyp and medusa stage What is the dominant stage for each class Class Anthozoa Polyp stage only Class Scyphozoa Medusa stage dominant Polyp stage reduced/absent Which class do these examples Class Hydrozoa belong to Polyp stage is dominant Do all these have both a polyp and medusa stage What is the dominant stage for each class