Are sessile animals that have specialized cells called amoebocytes and choanocytes.

Sponges are sessile animals that have specialized cells called amoebocytes and choanocytes.

Sponges (phylum Porifera) are one of the simpllest multicellular organisms (first to branch off the evolutionary tree from the common ancestor of all animals) that have bodies full of pores and channels allowing water to circulate through them. Sponges’ s structure consists of two thin layers of cells and mesohyl layer between them. They don’ t have real tissues or organ systems such as nervous, digestive or circulatory systems. Constant water flow through their openings and pores obtain food and oxygen and remove wastes.

the relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell. reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.