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Agar, a natural polysaccharide, builds up in the cell wall of agarophytic algae in crystallized cellulose fibrous form. They work like a polysaccharide reserve in there. That being said the agar content varies season to season. Initially Golgi complex secretes a sulfated intermediate agar of low molecular weight, which later gets deposited into cell wall and gets enzymatically polymerized desulfates. The left over product is called agropectin. The electron microscopic imaging showed that the very thick cell wall of Gelidium sesquipedale contains agar and the rhizoids contain high MW agarose molecules. This might be possible because of the smaller rhizoidal cells are more abundant in higher water movement areas, thus supporting the fact that the water current plays very important role in the abundance of agar and agarose in weed’s cell wall. Table 5.1 describes the taxonomic classification of agar.

Table 5.1 Classification of the taxa of agarophytes [9].

Phylum	Class	Order	Family	Genus	Species
Rhodophyta	Florideophyceae	Gelidiales	Gelidiaceae	Gelidium	Gelidium sesquipedale
					Gelidium amansii
					Gelidium robustum
					Gelidium pristoides
					Gelidium canariense
					Gelidium rex
					Gelidium chilense
				Gelidiella	Gelidiella
				Pterocladia	Pterocladia capillacea
					Pterocladia lucida
		Gracilariales	Gracilariaceae	Gracilaria	Gracilaria chilense
					Gracilaria gigas
					Gracilaria edulis
					Gracilaria gracilis
					Gracilaria tenuistipitata
				Gracilariopsis	Gracilariopsis lamaneiformis
					Gracilariopsis sjostedtii
		Ahnfeltisles	Ahnfeltiaceae	Ahnfeltia	Ahnfeltia plycata