Download Review sheet – Chapter 7a (Porifera, Cnidaria, Ctenophora)

Review sheet – Chapter 7a (Porifera, Cnidaria, Ctenophora)
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Know that sponges, cnidarians and ctenophores belong to kingdom animalia which is in domain
eukarya
Know that all animals are eukaryotic
Know that all animals are multi-cellular and heterotrophic
Understand that a vertebrate possesses a backbone, while an invertebrate does not
Know that 97% of all animals are invertebrates
Know that 8/10ths of all animals are Arthropods (phylum Arthropoda)
Understand that sponges belong to phylum Porifera which means “pore bearer”
Understand that sponges lack true tissues and organs
Understand that sponges are the simplest of all animals
Know that all sponges are sessile and have no body symmetry
Know that the tiny pores found on a sponge are called ostia
Understand that sponges are filter-feeding suspension feeders
Understand that all filter feeders are suspension feeders, but not all suspension feeders are
filter feeders
Know that the collared feeding cells of sponges are called choanocytes
Understand that choanocytes have a flagella that generates a current and a thin collar that traps
and collect food particles
Understand that many sponges have spicules – supporting structures made of silica and/or
calcium carbonate
Understand that many sponges also have a protein called spongin which supports the sponge
Know that the wandering cells of a sponge are called amebocytes
Know that amebocytes secrete/produce spongin and spicules
Understand that amebocytes transport and store food particles, and can change into other cell
types
Understand that the silica used to make spicules comes from diatoms and other silica-based
protists (ex. radiolarians)
Understand that boring sponges bore into shells and word by use of an enzyme
Understand that sponges reproduce sexually and asexually
Understand that young/larval sponges are meroplanktonic
Understand that choanocytes and amebocytes produce eggs and sperm
Know that cnidarians have radial symmetry
Understand that cnidarians have an oral and an aboral surface; and that the oral surface is
where the mouth is (be able to label if given a diagram)
Understand that all cnidarians possess stinging cells called nematocysts
Understand that cnidarians occur as a polyp form where the mouth and tentacles face upward
and a medusa form where the mouth and tentacles face downward; both of which possess
radial symmetry
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Understand that some cnidarians exist as only a polyp or medusa, while others have both a
polyp and medusa stage
Know that Class Hydrozoa is a class of very small Cnidarians, which includes Order Siphonophora
Understand that the Portuguese Man o’war and By-the-wind sailer are siphonophores
Know that Class Scyphozoa is a class of Cnidarians which includes the true jellyfish; understand
also that these are typically larger than the medusa-like Hydrozoans and have a short polyp
stage followed by a long medusa stage
Understand that even though Schyphozoans can swim by contractions of their bell, they are
considered planktonic because they cannot swim against a current
Know that Class Anthozoa is a class of Cnidarians which includes the corals, sea anemones and
sea fans
Understand that Anthozoans lack a medusa stage and exist only as a polyp stage
Know that ctenophores, or comb jellies, belong to phylum Ctenophora
Understand that ctenophores have colloblasts (sticky cells) and do not have nematocysts
Understand that ctenophores have 8 rows of cilia
Understand that ctenophore means “comb bearer”