There She Blows!
Sponges like a whale, have a “blow” hole. But, in the sponge it is called the osculum. The osculum is used in digestion but also as a means to remove undesired water from around the sponge. The flagellum or choanocytes, build up pressure in the central core of the sponge. Watch Out! All that pressure is then released causing water to shoot out long distances.