AP BIOLOGY

Detailed explanation-1: -Because sponges are sessile, meaning they cannot move, they filter water to obtain their food. They are, therefore, known as filter feeders. Filter feeders must filter the water to separate out the organisms and nutrients they want to eat from those they do not.

Detailed explanation-2: -In order obtain food, sponges pass water through their bodies in a process known as filter-feeding. Water is drawn into the sponge through tiny holes called incurrent pores.

Detailed explanation-3: -The Porifera are primarily filter feeders, utilizing food particles suspended in the water and captured by the choanocytes. Food particles consist essentially of bacteria, other microorganisms, and particles of organic debris; sponges also probably absorb dissolved organic substances.

Detailed explanation-4: -Sponges are unusual animals in that they lack definite organs to carry out their various functions. The most important structure is the system of canals and chambers, called a water-current system, through which water circulates to bring food and oxygen to the sponge.