Yes, they do.
Sponges have a variety of defenses against predators, including producing toxins, secreting a distasteful substance, releasing mucous to trap predators, and being able to quickly regenerate if damaged. Some sponges can also contract or close their pores to protect themselves.
Purple tube sponges have few natural enemies due to their chemical defenses and habitat preferences. However, they may be consumed by some predators, such as sea urchins, certain nudibranchs, and some fish species. Overcrowding and competition for space with other filter feeders can also pose a threat to purple tube sponges.
No, sea sponges are not decomposers. Sponges are filter feeders.
no sponges are not unicellular.
no sponges do not have bones
No, sponges are not parasitic.
Sponges are asymmetrical, although a few species have nearly radial symmetry.
To answer your question no sponges do not hibernate
No. Sponges are animals, which are heterotrophic.
Yes sponges have organs.
No sponges lack organized multicellular organs, such as nerves and muscles.
If you're talking about kitchen sponges, they do not have cells. However, sea sponges have cells.