MARS 294 – Spring 2013
Review Sheet - Second Exam
I. Invertebrates
 General characteristics, broad evolutionary relationships
II. Porifera (Sponges)
 Structural simplicity, cellular level of organization
A. Body Plan – Radial or irregular symmetry, ostia, osculum, spongocoel, pinacocytes, porocytes,
choanocytes, spongin, spicules, archaeocytes, asconoid, syconoid, leuconoid
B. Feeding – Sessile, suspension feeders (filter feeders), pump water, ingest plankton and particles
C. Reproduction – Asexual, sexual, hermaphroditic, internal fertilization, amphiblastula, life cycle
D. Diversity – Encrusting, glass, boring, sclerosponges
E. Ecology – Symbionts, commensal animals, food for other animals
III. Cnidaria
A. Body Plan – Radial symmetry, true tissues, polyp, medusa, systems (nervous, digestive), incomplete
digestive tract, body layers (epidermis, mesoglea, gastrodermis), cnidocytes
B. Hydrozoa – Characteristics, polyp specialization, reproduction, siphonophores, toxicity, feeding
C. Scyphozoa – Medusa, size, photoreceptors, zooxanthellae (some), swimming (bell), feeding, life cycle
D. Anthozoa – Most diverse, growth forms (solitary, colonial), feeding (septa), anemones, corals (stony –
massive, branching, soft), hermatypic, precious corals, gorgonians (sea whips, sea fans), sea pens,
sea pansies
E. Cubozoa – Sea wasps, box jellyfish, highly toxic, diet
IV. Ctenophora
 Radial symmetry, locomotion, ciliary combs, diet, prey capture, colloblasts, ecology (swarms)
 Body forms (tentaculate - planktivores, lobate – eat other ctenophores)
V. Platyhelminthes
 Body shape, bilateral symmetry, cephalization, organs, organ systems, central nervous system,
incomplete digestive system, three cell layers (ectoderm, mesoderm, endoderm)
A. Turbellaria – Characteristics (free-living), some commensal species
B. Trematoda – Characteristics (parasitic), life cycles (vertebrate host, intermediate host)
C. Cestoda – Characteristics (parasitic), structure
VI. Nemertea
 Complete digestive tract, circulatory system, trophic mode (proboscis), lifestyle (cryptic), distribution
VII. Lophophorates
- Lophophore, suspension feeders, bilateral symmetry, coelom, U-shaped gut, suspension feeders
A. Ectoprocta (bryozoans) – Basic anatomy, characteristics
B. Phoronida (horseshoe worms) – Basic anatomy, characteristics
C. Brachiopoda (lamp shells) – Basic anatomy (shells, pedicle), characteristics
VIII. Corals
- Hermatypic, mutualism with zooxanthellae, polyp structure, growth forms
A. Reproduction – Sexual (planulae larva), asexual, relative importance
IX. Coral Reefs
A. Distribution
B. Conditions – Substrate, light, temperature (bleaching, thermal tolerance limits), salinity, sediments,
pollution, tidal regime
MARS 294 - Spring 2013
Review Sheet - Second Exam
C. Components & Dynamics – Coralline algae, bioerosion
D. Structure – Zones on reef (front, crest, algal ridge, flat), depth ranges on slope, spur and groove
E. Types – Fringing, barrier, atoll, conditions, formation
X. Coral Reef Ecology
- Productivity
A. Trophic structure – Nutrient cycling, nitrogen fixation, food webs (resource partitioning, niches)
B. Competition – Between corals, mesenterial filaments, sweeper tentacles, soft corals
C. Predation – Nonlethal (fishes), lethal (crown-of-thorns sea stars)
D. Grazing – Herbivorous fishes, invertebrate grazers, microherbivores
E. Mutualism – Corals, clams, zooxanthellae, anemones, fishes, crabs, shrimps
XI. Annelida
 Mostly segmented, coelom, hydrostatic skeleton, longitudinal muscles, radial muscles, locomotion
A. Polychaeta – Parapodia, setae, gills, closed circulatory system, trochophore larva, lifestyle (errant,
sedentary), feeding (predators; deposit feeders – selective, nonselective; suspension feeders – active,
passive – solitary, colonial) , reproduction (epitoky)
B. Sipuncula (Peanut worms) – Distribution, structure (unsegmented, introvert), behavior (cryptic),
deposit feeding, reproduction
C. Echiura (Spoon worms) – Distribution, feeding, ecology, reproduction
D. Pogonophora (Beard worms) – Structure, no mouth/gut, trophosome, symbiotic bacteria, ecology,
Vestimentifera
XII. Nematoda
 Distribution, abundance, hydrostatic skeleton, locomotion (longitudinal muscles)
XIII. Benthos – Soft Bottom
A. Species composition – Epifauna vs. infauna
1. Megafauna – Definition, distribution
2. Macrofauna – Definition, distribution, characteristics (mechanically resistant, highly
mobile, both), examples, zonation
3. Meiofauna – Endobenthic, mesobenthic, characteristics (small, vermiform/flattened,
strengthened, adhesive/gripping structures, statocysts), trophic modes (deposit feeders,
predators, microherbivores), reproduction, examples
XIV. Mollusca
- Soft body, unsegmented, bilateral symmetry, mantle, shell structure (periostracum, prismatic layer,
nacreous layer), foot, radula, gills
- For each taxonomic class: characteristics, basic anatomy, diet/trophic mode (most cases),
reproduction, examples
A. Gastropoda – Shelled, nudibranchs (cerata, aposematic coloration),
B. Bivalvia – Burrowing, byssal threads, shipworms,
C. Cephalopoda – Mobility, coloration,
D. Polyplacophora
E. Scaphopoda
F. Monoplacophora
Review Session: Sunday, March 17, 5:00-7:00 pm, ST232