What is the function of choanocytes in sponges?Multiple choice question.They are small openings in the body of the sponges, through which water carrying oxygen and food enters the sponge.They act as a protecting layer around the body of the sponge, as they line its outer surface.They are specialized cells that assist in the circulation of water and the capture and digestion of food particles.They secrete needles of calcium carbonate or silica known as spicules.

In sponges, what is the function of the tiny pores in the body known as ostia?Multiple choice question.They allow water to enter the channels of the body.The main function of ostia is to allow sperm cells to enter the body of a spongeSponges are filter-feeders and ostia act as their food-collecting filters.Water loaded with wastes can exit the sponge through the ostia.

The tough skeletal fibers and spicules that support the body of a sponge are formed by what type of cells?Multiple choice question.ChoanocytesAmoeboid cellsCnidocytesEpithelial cellsNeed help? Review these concept

What are the flagellated cells that line the internal cavity of a sponge and help water flow through the ostia called?Multiple choice question.ChoanocytesSpiculesAmoebocytesEpithelial cellsCnidocytes

What type of cells surround the body of a sponge?Multiple choice question.SpiculesEpithelial cellsChoanocytesAmoebocytes

Certain epithelial cells around ostia in a sponge can contract, closing the tiny pores in the sponge's body. Why are these epithelial cells important?Multiple choice question.These cells are important for maintaining the water balance of the sponge.These cell close the ostia when there is too little oxygen in the water, protecting the sponge body from the accumulation of CO2.When ostia are closed the delicate inner cells of the sponge are protected against potentially harmful substances.