In animals, the plasma membrane is the outer boundary of the cell, even though in plants and prokaryotes it is typically protected by a mobile wall. However, intricate multicellular organisms evolved only in 6 eukaryotic teams: animals, fungi, brown algae, purple algae, eco-friendly algae, and crops. Complex sugars consumed by the organism can be broken down into simpler sugar molecules known as monosaccharides these as glucose.