Metazoan flashcards

Lichens and their symbiosis

the result of a symbiosis b/w ascomycota + (algae or cyanobacteria) + yeast

fungi provide shelter, algae or cyanobacteria produces food from photosynthesis, yeast protects by producing toxic vulpinic acid

porifera

• spicules

• (silica/calcium)

• networks of collagen

• choanocytes = filter water and capture food

• asymmetrical

• no gut

• ex: Sponge

ctenaphora

• use rows of cilia to move themselves (cilia in rows called combs/stenes)

• radial symmetry

• diploblastic development

• complete gut

• ex: comb jellies

cnidaria

• sting-bearing nematocysts/cnidocytes for protection and capture of prey

• polyp reproduces by budding or fission

• can be polyp or medusa forms

• 2 way gut

• radial symmetry

• ex: corals, sea anemone, box jellies, true jellies (jelly fish),

Annelida

• bilaterally symmetrical

• coelomate

• protostomes with segmented (metameric) body each segment

• each segment with paired bundles of chitinous setae, and parapodia (polychaetes) only

• body wall with inner longitudinal and outer circular muscles

• each segment the same

• each unit contains locomotory, reproduction, excretory, and respiratory structures

• triploblastic (mesoderm)

• complete, 1 way gut

• cephalized

• spiral, mosiac cleavage

• trochophore larvae

• ex: leeches, earthworms, bristleworms

Mollusca

• bilateral symmetry

• (secondarily asymmetrical)

• coelomate

• protosomes with

  • complete gut

  • reduced coelom open

  • circulatory system in most

  • well developed nervous system (especially in cephalopods)

  • trochophore larvae

• synapomorphies:

  • mantle (4 functions)

  • foot (radula (inside mouth)

  • spiral

  • mosaic cleavage

  • cephalization

• ex: chitons, bivalves, gastropods (snails and limpets), and cephalopods (squid)

Arthropoda

• protostomes

• bilateral symmetry

• exoskeleton

  • more energy required to shed and secrete new exoskeleton regularly, and are vulnerable until new one hardens

• grow in size by molting exoskeleton

• reabsorb nutrients before completely shed old skeleton

• muscles are attached to basement cuticle, under layer that sheds

• segmentation

• ecdysis

• triploblastic

• 1 way complete gut

• cephalization

• horseshoe crabs & insects=

  • 3 tagmata

• jointed appendages

• (crustaceans have specialized appendages for feeding, walking, and swimming)

• insects are hemimetabolous

  • (make small increases in body size w/ each molt and juvenile resembles adult)

• or are holometabolous

  • dramatic changes in form during their life

  • ie: caterpillar to butterfly

• ex: spiders, scorpions, horseshoe crabs (living fossils), centipedes, crustaceans, insects

echinodermata

• Adults= radial symmetry (usually pentaradial)

• deutrosomes

• able to regenerate tissue, organs, limbs,

• reproduce asexually

• ossicles

• calcite endoskeleton

• water vascular system

• tube feet

• radial, regulative cleavage

• ex: sea stars, sea urchins, sand dollars, sea lillies, and sea cucumbers

chordata

• have notochord

• bilateral symmetry

• deuterostomes

• coelomates

• vertebrate

• can have body plans organized via segmentation

• Postanal tail

• endostyle

• dorsal, hollow nerve cord

• triploblastic

• complete one way gut

• ex: fish, reptiles, birds, mammals, sea urchins, amphibians, sea squirts, and lanceletes.