Sponges and Cnidarians *EC*

Extra credit flashcards

Basal Disk

Structure that forms a sticky substance and allows for attachment to an area

Cephalization

Having a centralized nervous system at the front of the body, like a head.

Leuconoid

Sponge body type containing a network of chambers for the inlet and outlet of water. Allows them to grow larger and in different formations.

Amoebocytes

Sponge cells that absorb nutrients

Polyp

tube like, sessile form of a jellyfish

Syconoid

Sponge with a body wall that is pocketed with choanocytes. The pockets are attached to ostia and increase the pumping capacity of the sponge, allowing it to grow larger.

Spongin

Flexible protein fiber that makes up sponges

Medusa

free floating bell shaped form of jellyfish

Asymmetrical

Irregular in shape

Radial Symmetry

Animal can be divided up around a central rotational axis

Asconoid

Simplest sponge body structure. Tube or vase shaped, with very few cell layers. Very small size due to limited surface area

Spicule

Tiny calcium or silica needles

Bilateral Symmetry

Animal has mirror image right and left sides, and can be divided only along a central axis

Hydrostatic Skeleton

A support structure that uses water pressure to keep the animals shape.

Cnidocytes

Stinging cells

Nematocysts

harpoon like stinging cells contained within the cnidocytes

Choanocytes

Collar cells. beats their flagellum to draw in water

Sessile

remaining in one spot for the rest of its life

Ostium

Tiny pores through which water enters

Osculum

larger opening through which water exits