Lab Midterm 1 Flashcards
What are the characteristics of the Phylum Ciliophora?
- Most unicellular; some colonial
- Cilia used for locomotion
- Body shape maintained by protein-fibrous pellicle
- Have both macro- and micronuclei
- Most with cytostome (=cell mouth)
- Reproduce asexually (fission) or via conjugation
What are the characteristics of the Phylum Dinoflagellata?
- Two flagella in grooves: one transverse, one longitudinal.
- Both photosynthetic and hetertrophic forms; many can switch
- Some are bioluminescent
- Most are unicellular, but some form colonies
- Population booms cause “red tides”
- Many photosynthetic forms are endosymbiotic in other protozoans and animals such as corals
What are the characteristics of the Phylum Apicomplexa?
- Unique apical complex (not visible with light microscope)
- Lack cilia, flagella, pseudopods
- All are parasitic
- Gregarines infect various invertebrates
- Coccidians infect mostly vertebrates
What are the characteristics of the Phylum Euglenozoa?
- Have 1 or 2 flagella
- Single nucleus
- Reproduce asexually (fission)
- Includes free-living and parasitic forms
- Euglenids are mostly free-living
- Have proteinaceous pellicle to hold shape
- Most are photosynthetic via secondary
endosymbiosis - Kinetopastids are mostly parasitic
- Flagellum forms edge of undulating membrane
along elongted cell
- Greatly elongated mitochondrion (stained dark in
photo)
- Many have complex life cycles, often with
multiple hosts
What are the characteristics of the Phylum Amoebozoa?
- Cell surrounded by plasma membrane; some form an external test
- Pseudopodia used for locomotion
- Most free-living, but a few are endosymbiotic, either commensal or parasitic
- Reproduce asexually (fission)
- The classification of ameboid protozoans remains controversial
What are the characteristics of the Phylum Foraminifera?
- External test (skeleton), usually of calcite (CaCO3)
- Tests usually a series of chambers of increasing size
- Tests have 1 or 2 holes through which pseudopods are extended
- Heterotrophic, but some have symbiotic algae
Marine
What are the characteristics of the Phylum Radiolara?
- Limited to no locomotion
- Internal siliceous skeleton; typically with elaborate structure
- Have axopods similar to Heliozoans, but these are not visible in dead tests
- Heterotrophic, but some have endosymbiotic dinoflagellates
- Marine waters only
What are the characteristics of the Phylum Porifera?
- Multicellular, but lack true tissues
- Asymmetrical or radial symmetry
- Adults sessile suspension feeders
- Internal skeleton composed of spicules (calcium carbonate or silicon dioxide) or collagen fibers
What are the characteristics of the Class Demospongiae (Porifera)?
- Includes majority of sponges
- Spicules composed of silicon dioxide or replaced by spongin (collagen network)
- Nearly all have leuconoid grade of construction
- Diverse marine and fresh water habitats
What are the characteristics of the Class Calcarea (Porifera)?
- Spicules composed of calcium carbonate
- Spicules not usually differentiated into mega- vs microscleres
- Includes species with Asconoid, Synconoid, and -
Leuconoid body forms - Marine
What are the characteristics of the Class Hexactinellida (Porifera)?
- Glass Sponges
- Spicules composed of silicon dioxide, 6-rayed; complex skeletons
- Radially symmetric
- Syconoid and leuconoid body forms
- Lacks outer pinacoderm layer
- Deep water marine
What are the characteristics of the Phylum Ctenophora?
- Diploblastic; endoderm & ectoderm separated by mesenchyme
- Biradial symmetry
- Gastrovascular cavity with anal pores
- No alternation of generations; no sessile stage
- 8 combs (rows of ciliary plates)
- Most with pair of long tentacles
What are the characteristics of the Phylum Cnidaria?
- Diploblastic; endoderm & ectoderm separated by mesoglea
- Radial symmetry
- Presence of cnidae/nematocysts in cnidocytes (stinging cells) (see photo at right)
- Alternation of polyploid (polyp) and medusoid generations
- Gastrovascular cavity with single mouth/anus
- Tissue grade organization
What are the characteristics of the Class Hydrozoa (Cnidaria)?
- Alternation of generations: polypoid generation usually dominant
- Medusae usually small, transparent
- A few (fire corals) produce coral-like calcareous skeleton
- Polyps usually colonial, with interconnected coelenterons
- No cells in mesoglea
- Nematocysts only in epidermis (not gastrodermis)
- Marine and fresh waters
What are the characteristics of the Class Anthozoa (Cnidaria - Anemones and Corals)?
- Lack medusoid stage
- Polyps solitary or colonial
- Coelenteron (gastrovascular cavity) subdivided by longitudinal folds of tissue
- Tentacles in multiples of 6 or 8
- Marine only
What are the characteristics of the Class Scyphozoa (Cnidaria)?
- Medusoid stage predominates; polyps inconspicuous
- Thick gelatin-like mesoglea
- Often pigmented
What are characteristics of the Phylum Platyhelminthes?
- Triploblastic, acoelomate
- Bilaterally symmetric
- Cephalization; with central nervous system
- Elongate, dorso-ventrally flattened
- Incomplete gut (gastrovascular cavity) or lack gut
- Free-living and parasitic forms
What are the characteristics of the Class Turbellaria (Platyhelminthes)?
- Free-living; mostly aquatic
- Epidermis ciliated
What are the characteristics of the Class Trematoda (Platyhelinthes)?
- Internal parasites with often complex life cycles
- Epidermis forms tegument
- Attach to host via oral and ventral suckers
What are the characteristics of the Class Monogenea (Platyhelinthes)?
- External parasites (or in open cavities) of aquatic organisms
- Distinctive posterior attachment organ
- Simple life cycle
What are the characteristics of the Class Cestoda (Platyhelinthes)?
- Parasites of vertebrate guts
- Epidermis forms tegument
- Attach to host via anterior scolex
- Trunk (strobila) greatly elongated, consists of numerous segmented proglottids
What are characteristics of the Phylum Rotifera?
- Very small, most <1 mm.
- Varied, complex shapes
- Anterior end has paired coronas lined with cilia
- Many forms are sessile, attach via posterior foot
- Mostly fresh water; a few are parasitic
- Most are parthenogenic
- Without Acanthocephalans, the group is paraphyletic
Clade that includes rotifers and acanthocephalans sometimes called Syndermata
What are characteristics of the Phylum Chaetognatha?
- Elongate, streamlined bodies
- Lateral & caudal fins supported by rays
- Mouth surrounded by grasping spines
- Complete gut
- Longitudinal but not circular muscles
- Pelagic marine predators
What are characteristics of the Phylum Bryozoa (Moss Animals)?
- Have lophophore (ciliated O- or U-shaped ridge around mouth)
- Three-part body plan with U-shaped gut
- Individuals tiny (<1 mm) but form colonies (via budding)
- Colonies have variety of forms (encrusting, branched, etc.)
- Each individual housed in a secreted casing (Cystid)
- Lophophore forms tentacles that can be protruded or retracted
- Mostly marine, some fresh-water
What are characteristics of the Phylum Brachiopoda (Lamp Shells)?
- Superficially Mollusc-like, with 2-valve shell
- One valve is dorsal, one ventral (mollusc valves are right and left)
- Have lophophore (ciliated O- or U-shaped ridge around mouth)
- Three-part body plan with U-shaped gut
- Usually with stalk (pedicle) to attach to substrate
Marine, benthic
What are characteristics of the Phylum Annelida?
- Well developed true coelom
- Segmented (reduced or lost in some)
- Complete digestive tract with regional specialization
- Closed circulatory system with respiratory pigments
- Well-developed nervous system
- Usually with lateral chaetae (spines) on each segment
- Marine, fresh water, and terrestrial environments
What are characteristics of the Class Polychaeta, Subclass Errantia (Bristle Worms)?
- Numerous chaetae (setae) on segments
- Most have parapodia
- Most have sensory tentacles and eyes on head
- Most have chitinous jaws
- Lack clitellum
- Mostly marine
- Mobile: crawl over substrates or swim
- The monophyly of this group is not certain
What are characteristics of the Class Polychaeta, Subclass Sedentaria (Tube and Fan-Headed Worms)?
- Parapodia and chaetae often reduced or lost
- Most are sedentary, living in burrows or secreted tubes
- Many with feathery tentacles for feeding
- Mostly filter feeders or suspension feeders
- This subclass may be paraphyletic
What are characteristics of the Class Clitellata, Subclass Oligochaeta (Earthworms)?
- Few chaetae; lack parapodia
- Little structural specialization of head
- Presence of clitellum (forms muscus and egg cocoon)
- Mostly in terrestrial or fresh water environments
What are characteristics of the Class Clitellata, Subclass Hirudinomorpha (Leeches)?
- Segmenting less defined; body not divided by septa
- Clitellum present
- Lack setae or parapodia
- Have a posterior sucker and usually also an anterior sucker
- Mostly in fresh water, a few are marine and semi-terrestrial
- May be scavengers, predators, or external parasites
