vocab def aice marine 11/4

Pinacocyte

flat cells on the outer surface of sponges

ostia

small openings in a sponge; waters entrance point

osculum

the large opening in a sponge; waters exit point

amoebocytes

wandering cells; cells that distribute materials and spicules throughout sponge

planula

planktonic larvae of many cnidarian

hermaphrodites

organisms that have both male and female gonads

medusa

cnidarian free floating stage (jellyfish)

nematocyst

spearing type cnida, which are discharged when the cnidocill, bristle like trigger, contacts another object

polyp

cnidarian benthic form form characterized by a cylindrical body with an opening at 1 end and mouth surrounded by tentacles

ctenophore

comb jellies

radical symmetry

many planes can be drawn through the central axis that will divide the animal into equivalent halves

choanocytes

collar cells, the cells ina sponge that are flagellated and trap food

porocyte

tube like cell of sponges that form spores