Sponge – Plant or Animal?
Sponges are animals, but very strange. They don’t have the body parts and don’t even move around. They stay attached to an underwater rock or coral reef and look like plants. That’s why for a long time people thought sponges were plants.
There are nearly 5,000 different kinds of sponges. Most of them live in the ocean, but a few live in freshwater.
They are different in shapes: may be flat like spreading moss or like trees with branching arms.
A sponge’s body is a soft mass of cells supported by a skeleton. Holes in a sponge’s skin let water flow inside.
A sponge gets oxygen to breathe from water through its body. They eat by straining the water around them. All sponges feed on tiny plankton. On average, they eat about 2/3 of their own weight. The water enters the body through a large number of openings, but it always leaves through a single opening.
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