EVERYDAY SCIENCE

Detailed explanation-1: -The simplest and least common sponge body form is asconoid. Ascon sponges have a vase-like body. Rarely do asconoid sponges exceed a diameter of 0.039 in (1 mm). A modified cell called a porocyte allows water to enter the sponge.

Detailed explanation-2: -The body of the simplest sponges takes the shape of a cylinder with a large central cavity, the spongocoel. Water enters the spongocoel from numerous pores in the body wall.

Detailed explanation-3: -Asconoid sponges are tubular with a central shaft called the spongocoel. The beating of choanocyte flagella forces water into the spongocoel through pores in the body wall. Choanocytes line the spongocoel and filter nutrients out of the water. Syconoid sponges are similar to asconoids.

Detailed explanation-4: -Most sponges fall into one of three categories, based on their canal systems-asconoid, syconoid and leuconoid. Asconoid sponges have the simplest type of organization. Small and tube shaped, water enters the sponge through dermal pores and flows into the atrium.

Detailed explanation-5: -d) Leucosolenia has the asconoid type canal system as it is a sponge. Clathrina is also another example. This type of canal system is found in the adult stages and the Olynthus stage of some calcareous sponges.