How is water moved through a sponges central cavity?

Water is moved through a sponge's central cavity, known as the spongocoel, by the action of specialized cells called choanocytes. These cells have flagella that beat rhythmically, creating a flow of water into the sponge through small openings called ostia. As water flows through the spongocoel, it is filtered for nutrients and oxygen, which are absorbed by the sponge's cells. The filtered water then exits through a larger opening called the osculum.