Animal-like Unicellular Eukaryotes PDF

Animal Like Unicells  The Kingdom Protista has been subdivided into 6 super groups that are thought to represent evolutionary relationships  four of the super groups contain organisms that are animal like.  Formerly grouped as the Protozoa  (pre-an...

Animal Like Unicells  The Kingdom Protista has been subdivided into 6 super groups that are thought to represent evolutionary relationships  four of the super groups contain organisms that are animal like.  Formerly grouped as the Protozoa  (pre-animals)  Unicellular Organisms  All processes of life are carried out within one cell  Unicellular Organisms  Structure  Pellicle  Microtubules under plasma membrane  Ectoplasm  Region of cytoplasm under pellicle relatively firm  Endoplasm  Inner region relatively fluid 8.02  Unicellular Organisms  Maintaining homeostasis  Feeding  Active transport  Endocytosis  Cytopharynx  Digestion in food vacuoles  Water balance  Saltwater unicells - isotonic  Freshwater - hypertonic to their environment 8.02  Unicellular Organisms 8.03  Maintaining homeostasis  Waste removal  Exocytosis  Diffusion  Gas exchange  diffusion  Reproduction  Asexual  Binary fission  Budding  Multifission (schizogony)  Sexual Generalized Animal Like Unicell Fig. 8.02 Unicellular Eukaryotes Animal-Like Life  Unicellular Eukaryotes Domain Eukarya (Has nucleus, organelles) Very diverse!! Any non-plant, non-animal, non-fungi eukaryote Unicellular  Unicellular Eukaryotes  Some are colonial  Mostly microscopic  Euk: Specialized organelles  Free-living or symbiotic  Locomotion : pseudopodia, flagella, cilia, etc, some sessile  Aquatic or terrestrial  Reproduce asexually or sexually  Nutrition  Heterotrophic  Ex: Saprozoic  (use nutrients dissolved in surrounding medium)  Autrophic Or both  Animal-Like Unicellular Eukaryotes  Major reorganization in 2005, ongoing  The Kingdom ‘Protista’ has been subdivided into 6 supergroups(for now) that are thought to represent evolutionary relationships  4 of the supergroups contain organisms that are animal- like.  Formerly grouped as the Protozoa (“pre-animals”) Which supergroup are animals in? Animal-Like Unicellular Eukaryotes  Major reorganization in 2020!!! Which supergroup are animals in? from https://www.sciencedirect.com/science/article/pii/  Animal-Like Unicellular Eukaryotic Supergroups 1. Excavata (no new supergroup YET)  Euglena  Trypanosoma 2. TSAR (Chromalveolata)  Plasmodium  Paramecium 3. (Rhizaria)  Foraminifera/Radiolaria 4. Amorphea (Amoebozoa)  Amoeba  Super Group Excavata  Suspension feeding groove  Posterior directed flagellum  Feeding by flagella generated currents  Examples  Fornicata  Parabasalia  Euglenozoa http://silicasecchidisk.conncoll.edu/Pics/Other%20Algae/ Other_jpegs/Euglena_Key225.jpg  Super Group Excavata  Fornicata  Unnucleated  Mitrosomes  uses anaerobic respiration  Giardia  Parabasalia  Multi-flagellated  endosymbiotic  Parabasal body  Hydrogenosomes  Cause Trichomonas  Euglenozoa  Phytoflagelled  Zooflagellated  One or two flagella http://silicasecchidisk.conncoll.edu/Pics/Other%20Algae/  Crystalline rod in flagella Other_jpegs/Euglena_Key225.jpg  Phytoflagellated Unicell  Euglena  Autotropic  Contain chlorophyll  Pyrenoid synthesizes and stores carbohydrates  One or two flagella  Important marine primary producers  Haploid and reproduce by binary fission  Zooflagellated Unicell  Trypanosoma  African Sleeping sickness  Heterotrophic  Single large mitochondrion  Important human parasites  Fatal if not treated 8.8  Zooflagellated Unicell  Trypanosoma brucei  Sleeping sickness  Passed by Tsetse flies  Tsetse fly is the intermediate hose  Multiplies in the gut then moves to salivary glad and matures in 15 to 35 days  Parasite moves into new host as the fly is getting its next meal  Advanced infections of the central 8.8 nervous system is fatal Supergroup: Trypanosoma Excavata (no new supergroup YET)  Super Group Amorphea -Amoebozoa  Amoeba and amoeba like protozoa  Naked or Shelled Amoebozoans  Examples  Tubulinea  Found just about anywhere that is moist  “standard” amoeba  Acanthamoebida  Found in soil and water has members that are important in human health  Flagellated and non-flagellated stage  Entamoebida  No flagella or centrioles and lack mitochondria  Use pseudopodia to catch food  Can be pathogenic responsible for Amoebic dysentery  Amoeboid movement the Pseudopodia  Lobopodia ( a)  Ectoplasmand endoplasm feeding and locomotion  Filopodia (b)  Ectoplasmonly, food conveyor-belt fashion  Reticulopodia (c)  Net-like filiopodia  Axopodia (d)  Microtubule surrounded by cytoplasm 8.9  Amorphea - Naked Amoebozoans  Shallow freshwater  Feedon protists and bacteria some parasites  Phagocytes  Reproduces by binary fission  Super Group Rhizaria  Amoeboidin morphology  Different based on molecular characters  Often with shells  Super Group Rhizaria  Foraminiferans  Primarily marine  Usually has a CaCO3 shell  Filopodia with granular cytoplasm  reticulopodia  Radiolarians  Radial symmetry  Planktonic  Silica or glass shell often highly ornate.  axopodia  Super TSAR - Chromalveolata  Diverse united by the presence of plastids  Alveolata  Dinoflagellates  Apicomplexa Veryimportant in human disease  Ciliophora  TSAR - Alveolata Dinoflagellata  Free living and in symbiotic relationships  Important group in phytoplankton  Both autotrophic and heterotrophic  Reproduce rapidly (can "bloom")  Red tide, also green and brown  Can create toxins (neuro, muscle,etc.) nib  paralytic shellfish poisoning  TSAR Alveolata Dinoflagellata 2 Flagella  Transverse  Longitudinal  Theca  cellulose cell wall  Reproduce by simple cell division nib  TSAR Alveolata the Apicomplexa  All members are parasites  Complex life cycle 2 or more hosts  Plasmodium causes malaria  Apical complex for penetrating host cells  Single nucleus type  No cilia or flagella  Sexual and asexual phases to life cycle. nib  TSAR Plasmodium Life Cycle  Three stages  Schizogony (1, 2, 3)  Multiple fission of an asexual phase in host  1st in liver cells the RBC  merozoites  Gametogony (4,5)  Takes place in the blood stream  Mosquito picks it up in bite  Gametocytes fuse  Oocyst  Resting phase  Sporogony (6)  sporozoites Like 8.15  TSAR - Plasmodium Life Cycle  Vertebrate and mosquito host  Symptoms are periodic  Correlateswith RBC ruptures and release of enclosed toxins Like 8.15  TSAR - Ciliophora  Around 8000 sp.  Relatively rigid pellicle,  Cilia for locomotion and relatively fixed shape feeding  Distinct cytopharynx/  Heterotrophic, some cytostome symbiotic some parasitic  Sexual and asexual  Free swimming reproduction  paramecium  Dimorphic nuclei  Attached  macronucleus  votticella  micronuclei TSAR - Ciliophora nib TSAR - Ciliophora nib  Structure  Pellicle  Cilia  Trichocysts  Contractile vacuole  Oral groove  Cytopharynx  Cytostome  Cytopyge  Micronucleus  Marconucleus 8.16  Locomotion  Cilia short hair like projection on the body  Coordinated waves  Beat forward or backward  Some show cilia specialization  Basal bodies connected  Anchor cilia structure for organism  Feeding  Heterotrophic  Eat other protozoans or small animal  Attached ciliates have tentacles to paralyze and suck out the cytoplasm.  Cilia sweep food partials into cytopharynx  Food vacuole forms  Indigestible material dumped to outside through cytopyge nib  Reproduction  Asexual  Binary fission  Sexual  Conjugation  8.20 Reproduction Conjugation  Random contact bring opposite mating types together  Conjugants adhere to each other  Plasma membranes fuse  Macronuclous breaks down  Meiosis results in four haploid pronuclei  8.20 Reproduction Conjugation  Three pronuclei break down  Pronuclei divides  Conjugants exchange micronuclei  Micronuclei fuse  diploid  Conjugants separate  8.20 Reproduction Conjugation  Micronuclei divides  One becomes the new Micronuclei  One becomes the new macronuclei  asexual reproduction follows  Animal linage is Monophyletic  Choanoflagellate sister group Animal  Similarities in Origins  Cell structures  Biochemistry  Molecular biology  Choanoflagellate  Group of flagellated unicells  Filter feed using a collar of microvilli  Move water with flagellum  Virtually identical to the sponge nib ( Porifera) feeding cell  Phylum Porifera  Sponges  9,000 to 10,000 sp.  Mostly marine A loose organization of cells  Some rudimentary division of labor  Range in size from a few centimeters to large enough to stand in.  Evolutionarily speaking the simplest animal  General Characteristics  Uniblastic  Asymmetrical or superficially radial  Three cell types  Pinacocytes  Mesenchyme cells  Choanocytes  No tissues or organs  Cavities or branching chambers that water is circulated through.  Sessile  Filter feeders  Sexual and asexual reproduction  Phylum Porifera  Spicules  Skeletal elements of sponges  Phylum Porifera  8,500–more than 25,000 species  Class Calcarea*  (8%)  Class Hexactinellida*  (8%)  Class Demospongiae*  ( 83%)  Class Homosclerophorida  ( 1 % around 117 sp.)  Class Schlerospongiae  ( 15 sp.)  Phylum Porifera  Class Calcarea  Three or four rays  CaCO3 calcium carbonate nib  Phylum Porifera  Class Hexactinellida  Glass sponges  Six rayed silica spicules  Normally fused nib  Phylum Porifera  Class Demospongiae  Siliceous or spongin spicules  Phylum Porifera  Class Schlerospongiae  Calcareous, Siliceous and spongin spicules  Usably leuconid body form  Found in the deep sea  Maybe Ceratoporella nicholsoni be a part of the Demospongiae  Basic Sponge Plumbing  Osculum  Ostia  Spongocoel  Choanocytes 9.6  Sponge Morphology  Pinacocytes  Outer covering  Contractile  Porocytes  Mesohyl  Sponge Morphology  Mesohyl  Jellylike layer  Mesenchyme cells  Amoeboid  Reproduction, secreting skeletal elements, transporting food  Sponge Morphology  Choanocytes  Lining the inner chamber  Flagellated collar cells  Choanocyte Structure  Flagellum  Collar  Cell  Food vacuole  Body Forms  Anconoid  Syconoid  Leuconid  Body Forms and Water Flow Ascon Osculum Ostia Spongocoel Choanocytes  Body Forms and Water Flow Sycon Osculum Dermal pores Spongocoel Radial canals Incurrent canals Choanocytes 9.6  Body Forms and Water Flow Leucon Osculum Dermal pores Choanocytes chambers Excurrent canals Choanocytes 9.6  Feeding  Filter feeding  Particles captured on collar of choanocytes  Digestion intercellular in food vacuoles  Phagocytosis  Active transport Gas Exchange and Waste Removal  O2 / CO2 exchange by diffusion  Nitrogenous waste removal by diffusion Types of Sexual Reproduction  Sexual  Monoecious  Both sexes in same animal  Dioecious  Each sex in a different animal  Sexual Reproduction in Porifera  Sexual  Monoecious  Both sexes in same sponge  Don’t self fertilize produce sperm and eggs at different times.  Choanocytes and amoeboid cells undergo meiosis to form gametes  Broadcast fertilization  Planktonic larvae  Asexual  Gemmules  Resting phase  Larval Types and Settlement  Larva  An immature stage that may undergo a dramatic change in structure before attaining the adult body form  Parenchymula  Amphiblastula General Things to Know About Each Group of animals we go over  Knowand spell correctly the domain, kingdom, phylum, class and sometimes order names. What you need to know  # species  where they live  #embryonic cell layers  feeding  level of organization  reproduction  symmetry  specific examples  coelom  morphology  novel characteristics  body systems  Radiate phyla Phylum. Cnidaria Class. Hydrozoa Class. Scyphozoa Class. Cubozoa Class. Anthozoa Phylum. Ctenophora Radial Symmetry nib Biradial Symmetry Modified radial caused by paired structures on a radial body plan nib Phylum Cnidaria 9.1 Phylum Cnidaria 9.23 Phylum Cnidaria Phylum Cnidaria  9,000 to 10,000 species  Mostly marine  Tissue level of organization  Diploblastic  Radial or biradial symmetry  Mesoglea  Gastrovascular cavity  Nerve net  Specialized cells Cnidocytes  Phylum Cnidaria  Feeding  Carnivores, predators, symbiotic relationship  Extra and intracellular digestion  Reproduction  Sexual and or asexual phases depending on class  Gas exchange  diffusion  Nitrogenous waste  ammonia  diffusion  Tissue Organization  Epidermis – derived from Ectoderm  Mesoglea  Gastrodermis – derived from Endoderm  Body Wall Structure  Outside  Epidermis  Epitheliomuscular cells  Epidermal nerve cells  Cnidocytes  Body Wall Structure  Middle  Mesoglea  Mostly acellular matrix  May contain amoeboid cells  Body Wall Structure  Inside  Gastrodermis  Ciliated  Nutritive-muscular cells  Cnidocytes  Enzymatic gland cells  Cnidocytes, Nematocysts  Foundin epidermis and or gastrodermis  Cnidocytes  Cells contain Nematocysts  Nematocysts  30 kinds  Sometimes with toxins  functions, attachment, defense, feeding Acoiled hollow tube that is shot out when stimulated  Barbed  Cnidocytes and Nematocysts Structure  Cnidocyte  Nematocyst  Operculum  Cnidocil  Two body forms  Polyp  Medusa  Sessile  Free swimming  Epidermis  Epidermis  Mesoglea  Mesoglea  Gastrodermis  Gastrodermis  Mouth  Mouth  Gastrovascular cavity  Gastrovascular cavity  Tentacles  Tentacles  Hydrostatic Skeleton  Bag of water under pressure  Fluids non-compressible  Gastrovascular cavity  Take water in  Close mouth  Contract muscles around GVC  fluid bag becomes rigid  Usefor muscle attachment  Movement  Support  Movement, locomotion  Polyp  Medusa  Muscle contraction against  Muscle contraction hydrostatic skeleton  Thick elastic Mesoglea  Sessile  Free swimming  Feeding  Food capture nematocysts  Incomplete gut  One opening, mouth  Gastrovascular cavity  Carnivores  High quality food, animal food  Zooplankton, small fish  Nervous System  Nerves arranged in irregular net  Ganglia present  No central nervous system  Present in the epidermal and or gastrodermal tissues  Nerve impulses one or both directions  Synaptic junction along axon  Complex Sensory nib structures in medusa  Reproduction Alternation of Generations  Polyp phase  Medusa phase  Asexual phase  Sexual phase  Budding  Dioecious  Colony formation  Broadcast fertilization Produces  Strobilation eggs/sperm  Planula larvae Planula larva nib  4 classes of Cnidaria  Class Hydrozoa  Class Scyphozoa  Class Cubozoa  Class Anthozoa  Class Hydrozoa  Mostly Small  Theclass with the most freshwater members  Both Polyp phase and Medusa phase  Nematocysts only on the epidermis  Gametes derived from epidermis released to outside  Acellular Mesoglea  Class Hydrozoa  Most groups show both polyp and medusa phases in the life cycle  Class Hydrozoa Obelia  Polyp phase  Gastrozooid  hydranth  feeding  Gonozooid  Reproduction  Produce medusa  Perisarc  Protein and chitin  Coenosarc  Continuous gastrovascular cavity 9.11  Class Hydrozoa - Gomionemus  Medusa phase  Manubrium  Radial canals  Ring canal  Ovary  Velum  Tentacles  Sensory structures  Nerve ring  Statocyst 9.12  Class Hydrozoa examples  nib Class Hydrozoa  Siphonophora  Physalia physalis  Portuguese man-of-war  Colony  Float +- 8 to 10 cm  Feeding tentacles up to 30 meters  Predator of fish  Predator of Physalia  Glaucus atlanticus - Sea slug  Class Hydrozoa  Float  Specialized medusa  Polyp types  Gastrozoid  Dactylozoi d  Gonophore nib nib  Class Scyphozoa  True Jellyfish  All marine  Polyp phase reduced or absent  Medusa phase dominant  No velum on medusa  Thick elastic Mesoglea  Mesoglea with amoeboid cells  Cnidocytes in both gastrodermis and epidermis  Gametes derived form gastrodermis  Ciliated gastrodermis  Very good predators  Scyphozoa Medusa Structure  Ring canal  Radial Canals  Marginal tentacles  Oral lobe  Gastric filaments  Gonads  Scyphozoa Medusa Structure  Rhopalium  Sensory lappets  Statocyst  ocelli  Scyphozoan Reproduction  Dioecious  Broadcast fertilization  Polyp phase reduced  ( 4 mm)  Medusa (10 cm)  Ephyra  Adult medusa  Sperm/egg  Planula  Scyphistoma  Strobila  Class Scyphozoa  examples  Class Cubozoa  Box jellies  Polyp phase very reduced or absent  9.17 Medusa phase dominant  Very good predators  Extremely Toxic  Helmet shaped bell  Long tentacles  Nerve ring  Complex eyes  Lenses, image forming ?  Class Anthozoa  Anemones, coral  Polyp phase dominant  No Medusa phase  Colonial and solitary  Limited locomotion  No cnidocil on cnidocytes  Ciliated gastrodermis  Cnidocytes on epidermis and gastrodermis 9.9  biradial  Difference Between Anthozoan and Hydrozoan Polyps  Pharynx  Mesenteries  gonads  cnidocytes  Mesoglea contains amoeboid mesenchyme cells  Anthozoan Polyp  Oral disc  Oral tentacles  Mouth  Siphonoglyph  Pharynx  Mesenteries in pairs  Mesentery filament  Gonads  acontri  gastrovascular cavity  Pedal disc Body wall Incomplete septum Complete septum Retractor muscle Gastrovascular cavity Siphonoglyphs Pharynx nib  Anthozoan Polyp  Longitudinal muscles  In mesenteries  Radial muscles  gastrodermis  Anthozoan Reproduction  Asexual  Pedal laceration  Longitudinal or transverse fission  Sexual  Monoecious  No self fertilizing  Protandry - male first  Dioecious  Fertilization in gastrovascular cavity or open water  Planula larvae  Settles forms polyp  Anthozoan  Anemones  Soft corals  Hard corals  Anthozoan  Anemones  Solitary or colonial polyps  Anthozoan - clone wars  Anthopleura elegantissima nib Anthozoan  Soft corals  Sea pens  Sea fans  Leather corals  Anthozoan - Hard Corals  Colonial  Extensions of the gastro  All polyps of the colony vascular cavity connected  Rests on CaCO3  Tissues covering skeleton secreted by 3 lower epidermis layers  No siphonoglyph  Upper epidermis  Individual polyps small  Gastrodermis 1 - 3 mm  Lower epidermis  Colonies very large  Hard coral polyp structure  Tentacles  Mesenteries  Pharynx  Mesenterial filaments  Calyx  Theca  Basal plate  Sclerosepta nib  Anthozoan  Symbiotic relationship with Dinoflagellate  Zooxanthellae  Coral gets organics  Zooxanthellae gets nitrogen and phosphorus from coral  Zooxanthellae also assists in deposition of CaCO3 skeleton Zooxanthellae nib Phylum Ctenophora  Phylum Ctenophora  Comb jellies  Colloblasts  Biradially symmetrical  Sticky feeding  Diploblastic  8 rows of cilliary bands  Tissues level of  Comb rows organization  Fused cilia  Cellular Mesoglea  Used for locomotion between epidermis and gastrodermis  True muscles cells  Ellipsoid or spherical in  Gastrovascular cavity shape  Nerve net  monoecious  Phylum Ctenophora  mouth  pharynx  Gastrovascular canals  Comb rows  Anal pore  Complete gut  Apical sense organ  Statocyst  Colloblasts 9.22  Ctenophoran structures Apical sense Tentacle organ Tentacle sheath Comb plates (Ctenes) Pharynx Mouth nib Apical sense organ Statolith Balancer Ctenes 9.22 Phylum Platyhelminthes The Triploblastic Acoelomate Body Plan  Patterns of Organization - Acoelomate  Triploblastic  Organ level of organization  Three embryotic cell layers  Ectodermis  Mesoderm  Endodermis  without body cavity or coelom  Patterns of Organization  The Acoelomate Phyla Higher Taxonomy  Phylum Platyhelminthes  20,000 sp.  Simple cephalization  Organ level of organization  Protonephridia for  Triploblastic excretory / osmorgulatory  Usually flattened structure dorsoventrally  Monoecious  Bilaterally symmetrical  Nervous system  Acoelomate  Anterior ganglia  Unsegmented worms  Longitudinal nerve cords  Incomplete or no gut connected by transverse  Free living and parasites nerves  endo  ecto  4 major classes  Turbellaria  Monogenea  Trematoda  Cestoidea  Class - Turbellaria  3,000 species  Mostly free living  Most are small, 1 cm, but nib some tropical and marine species are large up to 60 cm  Mostly carnivores  Fresh and saltwater a few terrestrial http://www.thefeaturedcreature.com/a-living- swimming-ribbon-the-glorious-flatworm/  Class – Turbellaria Body Structure  Ectodermally derived  Epidermis  Ciliated, microvilli  Mesodermally derived tissues  Circular muscles  Longitudinal muscle  Dorsoventral muscle  Parenchymal cells  Endodermally derived  Gastrodermis  Digestive cavity  secretes enzymes  absorbs  Class – Turbellaria Body Structure  Most organs to the exterior body wall  Ventral nerve cord  If present  Ventral, surface  Epidermis  Rhabdites  Mucus bags  Adhesion glands  Releaser glands  Cilia  Class – Turbellaria Locomotion  Creeping  Cilia  Muscular undulation  Sheet of mucus  Normally anterior first  Name from turbulence in the water created by cilia  Swimming  Muscular undulation  Class – Turbellaria Digestion  Blind cavities  Increase in complexity increased area for digestion and absorption  Groups based on gut complexity  Acoela  Tricladida  Polycladida  Class – Turbellaria Digestive System  Tricladia example Dugesia  Mouth opening  Pharynx  Pharynx sheath  Diverticula  Blind cavities  Important  Increase in complexity increased area for digestion and absorption  Takes the place of a circulatory system  Class – Turbellaria Digestive System  Eat  Small invert  Dead larger animals  Algae  Digestion  Extracellular breakdown  In digestive cavity  Particles taken into cells phagocytosis  Digestive completed intracellular  Class – Turbellaria Exchanges With Environment  Gas exchange  Simple diffusion  Metabolic waste removal  Simple diffusion  Class – Turbellaria Exchanges With Environment  Osmoregulation  Water balance  Marine flatworms isotonic with environment  Freshwater  Takes on water  Needs to get rid of it  Protonephridial system  Flamecell  Fenestration  Excretory tube  Nephridiopore 10.7  Class – Turbellaria Nervous System  Acoela  Subepidermal nerve plexus  Nerve net like  Statocycts  Tricladida  Subepidermal nerve plexus  Statocycts  Cerebral ganglia  Long nerve cords  Commissures  Lateral nerve branches Ladder like nerve cords  Class – Turbellaria Sensory Systems  Touch sensors  Chemical or olfactory  Pressure sensors  Statocycts  Ocelli  Negatively phototactic nib  Class - Turbellaria Reproduction  Asexual  Transverse fission  Zooids  Sexual  Monoecious  Mesodermally derived sexual system  Class - Turbellaria Reproduction  Male  Testis  Sperm duct  Seminal vesicles  Penis  Genital chamber  Female  Ovary  Oviduct  Vitellaria  Copulatory sac  Genital pore  Class - Turbellaria Reproduction  Cross fertilization  Eggs  Cocoon  Direct development  Gradual changes from hatchling to adult  Larva  Different form than adult with some sort of metamorphosis  Class - Monogenea  One generation in the life cycle  Ectoparasite on fishes  Attaches to gill, feed on  Epithelial tissue  Mucus  Blood  Opisthaptor  Posterior attachment organ  Ciliated larvae  Swims to new host develops into adult  Class- Trematoda  8,000 sp.  As adults all endoparasites  1 mm to 6 cm in size  Flukes  Several generation in life cycle  Host for adult usually vertebrate  Tegument  Specific body wall type  Feed on host cells  Class- Trematoda  Tegument  Body wall for parasitic lifestyle  Outer zone  Glycocalyx  Microvilli  Basement membrane  Cytoplasmic bridge  Inner zone  Nucleus  Most organelles  Class- Trematoda Body Plan  Oral sucker  Mouth  Pharynx  Esophagus  Cecum  Acetabulum  Excretory vesicle  Nephridiopore  Class- Trematoda Body Plan  Ovary  Oviduct  Uterus  Vitelline gland  Testes  Seminal vesicle  Vas deferens  Class- Trematoda Complex Life Cycles  Two forms  Adult  Larvae ( can have many stages)  At least two hosts  Intermediate host  Definitive host  Host in which the parasite becomes reproductive  Liverfluke  Schistosome fluke  General Liver Fluke  Egg  Cercaria  Miracidium  Metacercaria  Sporocyst  Adult  Redia  In Water  egg Clonorchis Liver  Miracidium  Fluke Snail host  Sporocyst  Redia  Cercaria  Fish host  Metacercari a  Human host  Adult  In water  egg  Snail host Schistosome Fluke Life Cycles  Miracidium  Sporocyst  Redia  Free in water  Cercaria  No Metacercaria  Human host  Adult  Classes - Cestoidea  3,500 sp.  All endoparasites  Vertebrate digestive tract  1 mm to 25 meters  No mouth or digestive tract  Adults a long series of proglottids  Each has a complete set nib of reproductive organs  Classes - Cestoidea  3 body regions  Scolex  Neck  Strobila  Proglottids 10.18  Tegument body wall  Simplified body systems  No digestive system  Nervous system  Ganglia + 2 lateral nerve cords  Excretory system  protonephridial  Classes - Cestoidea  Reproductions  Monoecious  Proglottids  Immature  Mature  Gravid  Copulation between two mature proglottids or another tape nib worm Class - Cestoidea  Life cycle of beef tape worm 10.19  Phylum Nemertea  Ribbon worms  900 sp.  Elongate flattened  Marine  In sand and mud  Proboscis  Millimeter to centimeter size sometimes bigger  Carnivorous  Phylum Nemertea  Triploblastic  Acoelomate  Bilaterally symmetrical  Unsegemnted  Complete digestive tract  Protonephrida  Cephalization  Cerebral ganglion  Longitudinal nerve cords  Transverse commissures  Closed circulatory system  Proboscis  Feeding structure  Spear gun  stylet  Rhynchocoel  Phylum Nemertea  Reproduction Dioecious  Locomotion  External fertilization  Glide on a mucus trail  Pilidium larva  Cilia  Short larval period  Muscle contractions Tree of Life  http://tolweb.org/tree/phylogeny.html Higher Taxonomy  Coelomate (not fully lined in mesoderm) body plan members of the Lophotrochozoa and Ecdysozoa  Supraphylum  Grouping of phyla but more specific than a kingdom  Lophotrochozoa  Animals that do not molt, have a unique feeding structure with hollow tentacles or a trocophore larva  Ecdysozoa  Animals that do molt  Coelomate (not fully lined in mesoderm) body plan  Lophotrochozoa  Rotifera  Ecdysozoa  Nematoda  Tardigrada  Coelom  Fluid filled body cavity  Develops from blastocoel  Not fully lined with mesoderm  Muscles and organs in direct contact with coelomic fluid  Advantages of a Complete Gut  First group with complete gut  Food goes in one end  Waste out the other  Allows for sequential breakdown and absorption of food  Allows for specialization of regions and conditions in the gut  More efficient digestion  Coelomate (not fully lined in mesoderm) body plan The Nematoda and Rotifera -Aschelminthes  Around 32,000 sp.  unsegmented  Triploblastic  Cylindrical in cross  Organ level of organization section   Protonephridia Bilaterally symmetrical  Most dioecious  osmoregulation  No circulatory system  Some cephalization  No gas exchange system  Primitive brain  Most microscopic but  Sensory organs some can reach over a meter  mouth  Cuticle  Thin, tough, external covering  May have spines, scales, projections  Some molt to grow  Syncytial epidermis  Multi nucleated  secretes the cuticle  Rotifera  2,000 sp.  Corona  Characteristic ciliated organ  Feeding and locomotion  Small 0.1 to 3 mm  Mostly freshwater  Approximately 1000 cells  Free living  Filter feeders carnivorous  Rotifera  Triploblastic  Bilateral  Unsegmented  Coelomate, with a coelom not completely lined with mesoderm  Complete digestive tract with regional specialization  Posterior end with toes and adhesive glands  Protonephridia  Males reduced in number or absent  Rotifera anatomy  Head  Foot  Corona  anus  Mouth  toes  Brain  pedal glands  Flame bulb  Trunk  Lorica  Mastax, trophi  Thickened cuticle that covers the  Stomach body  Intestines  Cloacal bladder  Germovitellarium  Rotifera Reproduction  Sexual only  A mix of sexual and asexual reproduction  Haploid eggs and sperm  Based on environmental  Must be fertilized conditions  Both males and females  Amictic and Mictic cycles produced.  Produced males and females  Asexual only  Parthenogenesis  Diploid eggs  Produce only females   Mictic (n) eggs Amictic (2n) eggs  Thin shelled - meiosis  Thin shelled - mitosis  If not fertilized parthanogeneticly produces  Amictic ( 2n) males ( n) females  If fertilized thick shelled resting egg produced  Hatch into Amictic ( 2n) females  Nematoda  16,000 sp.  Most abundant animals on earth  Every feeding mode and on every type of organic material  Free living and parasitic  Microscopic to several meters long  No cilia  Except In sensory structures  Amoeboid sperm  Nematoda  Triploblastic  Bilateral  Vermiform  Unsegmented  Coelomate, with a coelom not completely lined in mesoderm  Body round in cross section  Elastic cuticle  Complete digestive tract with regional specialization  Excretory system  renette  Only longitudinal muscles  Noncellular  Elastic  Collagenous Nematoda Cuticle  Continues into foregut and hindgut  Three layers  Cortex  Matrix layer  Basal layer  Function  Maintains internal pressure  Mechanical protection  locomotion  Nematode Body Wall  Cuticle  longitudinal muscles  Projections from the muscles to nerve cord  coelom  gut  Nematoda  Digestive system  Mouth  Buccal capsule  Pharynx  Intestine  Anus  Nematoda  nervous system  nerve ring  Ganglia  dorsal and ventral nerve cord  Ampids  Anterior chemoreceptor  Phasmids  posterior chemoreceptor  Nematoda  Excretion/osmoregulation  Renette  Glandular  Excretory canals  Ammonia  principal nitrogenous waste  Reproduction  Dioecious  Males smaller than females  Dimorphic  Copulation - internal fertilization  Reproduction  Multi-step life cycles in parasitic forms  1 or more hosts  Ascaris  800 million infected  Trichinella ( trichinosis) Ascaris Trichinell a