Eukaryotic cell walls

This chapter describes plant cell walls as the best studied of the eukaryotic types, which consist of three basic layers: middle lamella, primary cell wall, and secondary cell wall. It clarifies that plant cells are glued together by a middle lamella, which separates their walls, and within the middle lamella is a primary cell wall. It also examines cellulose, which is the major carbohydrate of most plant cell walls and is the most abundant carbohydrate on earth. The chapter discusses algal cell walls that display an incredibly diverse composition and contain cellulose microfibrils and mannose or xylan-rich carbohydrates. It refers to filamentous fungal cell walls which are composed mainly of the polysaccharides glucans, chitin, and glycoproteins.