Porifera
The Porifera phylum consists of sponges. Sponges consist of about 5,000 species in the world, 150 of which live in fresh water. Sponges have cellular specialization, meaning that their cells can perform different jobs, but similar cells are not grouped into tissues to perform tasks. Their cells are loosely connected into a form. This is the simplest type of cellular organization.
Sponges are noted for having pores through which water pass through. Inside the pores there are flagellae which are located on special cells called choanocytes. The sponges are supported by a skeleton of the protein collagen and spicules. Skeletal elements, choanocytes, and other cells are imbedded in a gelatinous matrix called mesohyl or mesoglea. Sponges capture food and the food is brought into individual cells for digestion within the cell. The sponges capture this food using a water current generated by the choanocytes.
Sponges are noted for having pores through which water pass through. Inside the pores there are flagellae which are located on special cells called choanocytes. The sponges are supported by a skeleton of the protein collagen and spicules. Skeletal elements, choanocytes, and other cells are imbedded in a gelatinous matrix called mesohyl or mesoglea. Sponges capture food and the food is brought into individual cells for digestion within the cell. The sponges capture this food using a water current generated by the choanocytes.