Cell (biology) made up of cellulose, fungi cell walls are made up of chitin and bacteria cell walls are made up of peptidoglycan. A gelatinous capsule is present in some bacteria outside the cell membrane and cell wall. The capsule may be polysaccharide as in pneumococci, meningococci or polypeptide as "Bacillus anthracis" or hyaluronic acid as in streptococci. Capsules are not marked by normal staining protocols and can be detected by India ink or methyl blue; which allows for higher contrast between the cells for observation. Flagella are organelles for cellular mobility. The bacterial flagellum stretches from cytoplasm through the cell membrane(s)
Cell encapsulation and agarose have also been employed. Several groups have extensively studied several natural and synthetic polymers with the goal of developing the most suitable biomaterial for cell microencapsulation. Extensive work has been done using alginates which are regarded as the most suitable biomaterials for cell microencapsulation due to their abundance, excellent biocompatibility and biodegradability properties. Alginate is a natural polymer which can be extracted from seaweed and bacteria with numerous compositions based on the isolation source. Alginate is not free from all criticism. Some researchers believe that alginates with high-M content could produce an inflammatory response and an abnormal cell