Define the following terms: Sessile, polyp and collar cell? I hope I will get answer as soon as possible. Thanks!
Sessile is a property of an organism meaning the lack of locomotion. Sessile organisms are immovable and are attached to a certain surface.
A polyp is a sessile form of Cnidarians possessing an elongated cylindrical shape.
Collar cells (choanocytes) are cells that cover the body cavities of sponges. These cells contain a flagellum surrounded by microvilli connected by a thin membrane.