invertebrates pt 2 (cnidaria -> platyhelminthes)

corals, jelly fish, sea anemones, and hydras are part of what phylum?

phylum cnidaria

cnidaria are ______ with a radial body plan

diploblastic (ecto+endo)

→ this means they have tissue level development

what cavity do cnidarians have?

gastrovascular → a sac with one opening

→ meaning the mouth and the anus are the same

what level of development do cnidarians have?

tissue level

what 2 forms do cnidarians come in?

1) polyps

→ attach to the floor

2) medusas

→ free-floating

can cnidarians be a polyp and medusa in the same life cycle?

yes

what specialized feature do cnidarians have on their tentacles? what are they responsible for?

cells called cnidocytes

→ long, sticky threads used for self-defense and to capture prey

some cnidarians have cnidocytes that discharge stinging capsules. what are they called?

nematocysts

do all cnidarians have have cnidocytes? do all cnidarians have nematocysts?

all cnidarians have cnidocytes

but not all cnidarians have nematocysts, only some

phylum platyhelminthes

flatworms

→ they occupy marine, freshwater, and moist terrestrial habitats

what symmetry do phylum platyhemlinthes have?

bilateral

are platyhelminthes triploblastic?

yes

they have 3 germ layers (endo + ecto + meso)

are platyhelminthes free-living or parasitic?

can be both

platyhelminthes are acoelomates and have a ________ cavity with how many openings?

gastrovascular

1 opening

do phylum platyhelminthes have a body cavity?

no, they are acoelomates

marine flatworms and planaria are what type of platyhelminthes?

free-living

they are non-parasitic

fluke and tapeworms are what type of platyhelminthes?

parasitic

flukes are _________, meaning they have both male and female organs

hermaphrodites

what is a special feature of flukes?

they spend part of their life cycle in a vertebrate host (like snails and humans)

are tapeworms free-living or parasitic?

parasitic

what structures are unique to tapeworms?

scolex + proglottids

how do humans become infected by tapeworms?

by eating undercooked meats

what do proglottids contain?

reproductive structures