The major route for endocytosis in most cells, and the best-understood, is that mediated by the molecule clathrin. This large protein assists in the formation of a coated pit on the inner surface of the plasma membrane of the cell.This pit then buds into the cell to form a coated vesicle in the cytoplasm of the cell.he major route for endocytosis in most cells, and the best-understood, is that mediated by the molecule clathrin. This large protein assists in the formation of a coated pit on the inner surface of the plasma membrane of the cell.
Sponges are extremely primitive invertebrate life so are classed under the Kingdom Animalia, they do not photosynthesise so are not plants. They are also very different to fungi and have an entirely different composition and life cycle. A sponge if passed through a sieve gradually reforms its original shape.ponges are extremely primitive invertebrate life so are classed under the Kingdom Animalia, they do not photosynthesise so are not plants. They are also very different to fungi and have an entirely different composition and life cycle. A sponge if passed through a sieve gradually reforms its original shape.
It is believed that, there are around 5000 to 10,000 species of sponges, and most of them are found in sea water. So, sponges are unique aquatic animals with some interesting characteristics. Sponges are primarily found as a part of the marine biome; but, around 100 to 150 species can be found in freshwater.They may resemble plants, but are actually animals that are sessile (not capable of movements). So, sponges are made of these specialized cells, and they do not have any head, trunk, bodily organs, or appendages. 2  They are simple multicellular organisms. 3  Sponges are filter feeders, who absorb nutrients as well as oxygen from the water, that enters its body through the pores.