Advertisement Upgrade to remove ads


an opening in a sponge's body through which water exits


one of the small openings in a sponge's body through which water enters


any of the flagellate cells that line the cavities


an asexual reproductive structure produced by some freshwater sponges


within the body wall of a sponge, a specialized cell that crawls about and delivers nutrients from the choanocytes to the rest of the body cells


a needle of silica or calcuim carbonate in the skeleton of some sponges


a fibrous protein that contains sulfur and composes the fibers of the skeleton of some sponges


an independent and immature form of an organism that is morphologically different from the adult form


an organism that obtains organic food molecules by eating other organisms or their byproducts and that cannot synthesize organic compounds from inorganic materials


the outer surface layer of cells of a plant or animal

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording