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.
Why, you ask? Well, the term Porifera is actually the scientific name given to the group of organisms known commonly as sponges. But, unlike SpongeBob, living sponges are neither square in shape nor in interest-they are actually a really important and diverse phylum within the animal kingdom.owever, here we will focus on the key features of Porifera: choanocytes and spicules (formed by sclerocyte cells). Choanocytes, also known as collar cells, derive their name from the collar-like base where the flagellum (or tail) protrudes.