Sponges are not like fish,but I think that they have most of the same requirements as them.Sponges are living organisms so they need things for them to survive.Water is one of them,so if they are out of the water too long eventually they will dry out.I'm not sure what sponges eat or if they eat anything at all.Now that you mention it,I am going to have to look that up.If you have seen SpongeBob the movie,in one part of the movie this scubadiver puts SpongeBob under a bright light to dry him out,and he's a sponge.It doesn't sound scientific but it could be based on true science,but I doubt it.
It helps w/ reproduction and helps transport their young to new places to live.
What helps to
circulate and waste. Water helps to circulate food through the organism and also helps remove waste.
Helps to circulate water through xylem(transpiration pull),cools the plant.
When a sponge is submerged in water, the water enters the sponge through the tiny holes in the sponge. The sponge fills up with water, as a balloon fills with air, only not as visibly. When you squeeze the sponge, the water exits that sponge through the tiny holes...exactly the opposite of how it entered! Tada! :)
Water is held in the sponge until it is released.
A sponge takes in water through its pores and in more advanced forms, with canals that move the water to all throughout the sponge. Then the oxygen from the water is used.
through urine and water poles
The surface of the orange puffball sponge is covered with small pores that filter small particles of food from the water that passes through them. Each sponge has flagella that help move the water through the sponge.
The sponge uses the choanocytes to move a steady current through its body.
tiny "whips" on the cells inside a sponge draw water in through the pores of thesponge. Food is then removed from the water before it leaves through the opening at the top of the sponge .
Water is brought through cilia-lined pores into the hollow cavity of the sponge. As water passes through the pores, the cilia trap oxygen to breathe
The sponges are filter feeders, that means the surronding sea water circulate throught the canal system they have and the absorb the organic matter the water carries as their food.
"clean" water and "waste" water in a sponge are all the same. Their bodies allow constant flow of water, there is no beginning and end to a sponge; thus technically waste water leaves a sponges body through its many pores.