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Phylum Sarcomastigophora
§ Unicellular or colonial protozoa
§ Locomotion by flagella or pseudopodia (or both)
§ Autotrophic and heterotrophic
§ Homokaryotic (possess a single nucleus
§ Subphylum Sarcodina
§ Subphylum Mastigophora
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§ Subphylum Sarcodina
§ Amebae (plura) or Amebas (plural, but less commonly used)
§ Naked amebae used in lab with large false feet
- § Features : gel and smooth cytoplasm, ecto- and
- endoplasm, pseudopods, food vacuoles (digested by lysozomes), contractile
- vacuoles (expel H2O like a kidney)
- § They crawl; 3D gels slide like actin/myosin to make
- pseudopods travel
§ Amebae can carry a test (a housing structure used as protection, produced by the organism). They grab particles and build glue and housing structure
§ They feed on spirogyra
§ Species are distinguidhes by size or type of particles used
- § Sea urchins are another example; they have fused
- ossicles (small bones)
§ Phagocytosis (“cell eating”); uses pseudopods to grab food
§ Morphology=shape
§ Microtubules are 25 nm in length
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§ Subphylum Mastigophora
Class zoomasrigophorea (Zooflagellates)
Class Phytomastigophorea (Phytoflagellates)
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Class Phytomastigophorea (Phytoflagellates)
1-2 flagella
Store products as starch or paramylon
Primarily free-living
- Ex. Bacteria (food source) taken away, Paramecia will grow pseudopods to “run away” or grow
- flagella (ameboid)
§ Outer pellicle
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Class zoomasrigophorea (Zooflagellates)
Numerous flagella
Store anabolic products as glycogen
Free-living, many are parasites or symbionts
§ 1/3 of weight of termite
§ Peranema- feeds on euglena (a phytoflagellate)
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Phylum ciliophora (the ciliates)
§ Shape constant (or rigid) surrounded by pellicle)
§ Cilia for locomotion and feeding (infrastructure)
- § Two distinct types of nuclei (macronucleus- vegetative
- function, vs micronucleus-sexual reproduction + or -)
§ Asexual reproduction by binary fission
§ Sexual reproduction by conjugation (like in spirogyra)
Paramecium
§ Fires trichocyst
Flower looking. Will break off stalk and swim away
Cirri- larger than cilia. Can walk instead of swim
Didinium- eats paramecium
§ Shoot out cytostome
- § Sit and spin because it ate too much! Will eat again
- in 3 or 4 hours
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Phylum Porifera
§ Metazoan at the cellular grade of construction; without true tissues; adults asymmetrical or radially symmetrical
§ Cells tend to be totipotent
§ With unique flagellated cells—choanocytes—that drive water through canals and chambers constituting the aquiferous system
§ Adults are sessile (don’t move) suspension-feeders (filter feeding) larval stages are motile
§ Middle layer—the mesohyl—variable, but always includes motile cells and usually some skeletal material
§ Skeletal elements, when present, composed of calcium carbonate, silicon dioxide, and/or collagen fibers
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Phylum Cnidaria (sea anemones, jelly
fish)
§ 1 metazoa(have more than 1 cell)
§ 2. have mesoglia. Similar to mesohyll
§ 3. have radial symmetry
§ 4. nematocysts. Stinging cells. Only group that has these
- § 5. have a body cavity that is called the gastrovascular cavity. Single opening that serves as both mouth and anus. Incomplete digestive tract. Goes into coeleneron where it is digested, and then
- goes back through same epithelium where it was brought in
- Class Anthozoa
- Class schyphozoa
- Class Hydrozoa
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class anthozoa
corals, sea anemones
largest class in the phylum cnidaria over 15,000 species
exclusively marine forms
polyp of polypoid stage only, the medusa stage is absent (only class that does not have metagenesis)
reproduction- sexual and by budding (asexual). Fragmentation- in poor conditions (water quality bad), will reproduce asexually. Will move in one direction, but leave a little piece where it started. Will produce a clone of itself
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class schyphozoa
Jellyfish
Primarily marine (few in freshwater, but very rare)
Float usually in open seas
Tentacles numerous to few
Aurelia common genus throughout warm seas
Details of life cycle- metagenesis
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§ Class Hydrozoa
The hydrozoans (Hydra and Obelia common genera)
Marine and freshwater forms common
Division of labor
Coloniality
Polyp or medusoid stages in life cycles
Polyp of polypoid form (or morph) most common
Zooid types and functions
§ Gastrozooid- feeding zooid
§ Gonozooid- reproductive zooid
§ Dactylozooid- defense zooid, protects the colony***
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Phylum Platyhelminthes
- § Parasitic or free-living, unsegmented
- worms
- § Triploblastic (pertaining to metazoan
- in which the embryo has 3 primary germ layers-ectoderm, mesoderm, endoderm),
- acoelomate (no body cavity), bilaterally symmetrical; usually dorsoventrally
- flattened
- § Complex, though they have incomplete
- digestive track; just absent in some parasitic forms (cestoda)
- § Cephalized (cephalization = defined
- head region), with a central nervous system with a “brain” (a fusion of glial
- cells) and longitudinal nerve cords connected by transverse commissures
- (ladder-like nervous system)
- § With protonephridia (primitive
- excretory/osmoregulatory organ consisting of a tubule terminating internally
- with flame bulb or solenocyte; the unit of the flame bulb system)
- § Hermaphroditic, with complex
- reproductive system; monoecious
- Class Turbellaria
- Class Cestoda
- Class Trematoda
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Class Turbellaria
¨ Flatworms/ Planaria
¨ Freshwater, marine, and terrestrial
¨ Dorsoventrally flattened
¨ Carnivorous
¨ Monoecious; mostly cross fertilize for genetic variation
¨ Hypodermic impregnation: can carry a baby anywhere, like the head, back, etc.
¨ Fissiparity (splits in two down the middle) and fragmentation (budding) Ex. Halloween Planaria
¨ Pharynx is the center of the work that digest and excretes food. They can eat each other. Bright colors indicate bad taste (repugnatory glands are toxic). They have lots of mucus glands and are regenerative of body parts
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Class Cestoda
¨ The tapeworms
- ¨ All members are parasitic; about
- 4,500 species
¨ Internal parasites (endoparasites) vs ectoparasites
¨ Parasites of vertebrates primarily
¨ Scolex, head, or rostellum are important taxanomic characters
¨ Proglottids: segments or somites (reproductive units)
¨ No digestive tract
¨ Tegument (an integument, specifically, the external covering, formerly called a cuticle), syncytial (termed a syncyntium—many nuclei are present without any intervening membranes); multinucleated mass of cells formed by rapid mitotic division
- Hermaphrodites; gonochoristic (dioecious) or
- monoecious
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Class Trematoda
¨ the flukes
¨ all parasitic- 6,000 + species
¨ ecto and endoparasites
¨ non-ciliated epidermis
¨ various suckers on body
¨ parasites of fish, foul, mammals
¨ common Chinese liver fluke – Opisthorchis sinesis
¨ pseudocoelomate- not lined by mesoderm
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Phylum Rotifer
§ triploblasitc, bilateral, unsegmented pseudocoelomates
§ gut completely regionally specialized
- § pharynx modified as a mastax,
- containing jaw-like elements called trophy
- § anterior end often bears variable
- ciliated fields called a corona
§ posterior end often bears toes and adhesive glands
§ protonephridia present, no special circulatory or gas exchange structures
§ males generally smaller than females or completely absent in some species. Parthenogenesis is common (development of egg without fertilization by sperm)
§ marine, freshwater—sessile or free-swimming
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phylum Nematomorpha
- (horse hair worms- look like hair, and found in troughs)
- § triploblastic, bilateral, unsegmentes, and vermiform
- (worm-like) in shape, long and thin
§ cuticle well developed
§ gut reduced to various degrees, always nonfunctional in adults
§ larvae parasitic in arthropods (insects etc)
§ no special excretory, circulatory or gas structures
§ freshwater, some terrestrial, a ver few species in marine environment
§ dioecious
§ Thin, thread-like
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Phylum Kinorhyncha
§ triploblastic, bilateral, pseudocoelomates
§ body divided into 13 segments called zonites**
§ complete digestive track
- § one pair of protonephridia, no special circulatory or
- gas exchange structures
§ period molting (called ecdysis)
§ dioecious
- § inhabit marine, interstitial (to live between sand
- grains) environments
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Phylum Gastrotricha
§ triploblastic, bilateral, unsegmentes
§ with one to many pairs of adhesive tubes
§ cuticle (outer covering or epidermis) well-developed, often forming plates and spines
§ cilia restricted to ventral surface
§ complete digestive track
§ protonephridia present
§ monoecious and a dew dioecious forms known
§ freshwater or marine habitats
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phylum Acanthocephala
- § triploblastic, bilateral, unsegmentes, vermiform
- (=worm-like) pseudocoelomates
§ anterior end with hook-bearing proboscis
§ gut absent
§ protonephridia present, but greatly reduced in numbers compared to other pseudocoelomate phyla
§ dioecious
§ parasites of vertebrates, with very complex life cycles
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Phylum Nematoda
- § triploblastic, bilateral, vermiform (worm-like)
- unsegmented, pseudocoelomates
§ body round in cross section and the cuticle is complex and some species may shed or molt the cuticle during growth periods
- § gut complete, mouth surrounded by siz lips bearing
- sense organs
§ unique protonephridia called solenocytes
§ no special circulatory or gas exchange structures
§ body walls has only longitudinal muscles
§ dioecious
- § marine, freshwater, terrestrial and parasitic life
- cycles
§ Only have longitudinal muscles
§ Could be 90,000 nematodes inside a brown apple
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Phylum Nemertea
Triploblastic, acoelomate or coelomate. Bilaterally asymmetrical unsegmented worms
Digestive tract complete with anus
With protonephridia
With lobed, supraenteric cerebral ganglion; and two or more longitudinal, nerve cords connected by transverse commisures
With two or three layers of body wall muscles converges in various ways
With unique proboscis apparatus lying dorsal to the gut and surroung by a coelom-like hydrostatic chamber called the rhynchocoel
With closed circulatory system*********
Most are genochoristic early development typical spiakin eaiter direct or indirect
Brightly colored (warning). Can be very long. Use Retractor muscle. Rincoceal
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Phylum Annelida
Bilaterally symmetrical, segmented worms
Digestive tract complete, usually with regional specialization
With a closed circulatory sstem (some have multiple hearts)
Nervous system well developed
- Posess nephridia (many kidneys)- osmoregulatory
- and regulation of nitrogenous wastes
With paired, segmentally arranged setae bundles
Metameric body mass
Monoecious or dioecious
Marine, terrestrial and freshwater species
Metamerism- segmented body plan (anterior- posterior). Each segment almost the same. Allows them to move through peristalsis
- Class Polychaeta
- Class Hirudinea
- Class Oligochaeta
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Class Polychaeta
- Polychaete worms (many setae-
- extensions of the cuticle)
Setae = chaetae
Primarily marine (very few freshwater forms
Eversible pharynx –proboscis
Filter feeders
Deposit feeders
Errant forms (motile) Order Errantia
Sedentary forms (sessile) order Sedantaria
Clamworms most common genus – Nerreis
Sabellids (no operculum) vs Serpulids- (possess operculum = door)
Dioecious
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Class Hirudinea
§ Leeches
§ 2 suckers- usually anterior and posterior
§ Ectoparasites, but can also be detritivores (detritus
§ No setae (cuticular extensions)
§ No parapodia, characteristic of the class Polychaeta
§ Reduced coelom
§ Hypodermic impregnation
§ Estivate (go into hibernation if conditions are poor)
§ Monoecious and dioecious
§ Hirudin- anticoagulant like heparin
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Class Oligochaeta
§ Earthworms, freshwater worms. Lumbricus most common genus
§ 3100+ species
§ Terrestrial and freshwater forms
§ Metamerism- highly developed
§ Setae (=bristles) 1-2 per somite (segment)
- § Peristaltic movement (excellent burrowers and
- swimmers)
§ Lack eyes- possess ocelli
§ monoecious
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