The plant body is diploid (2n), erect and branched thallus (Fig. of axis of Sargassum. Sargassum contains higher amounts of protein essential 3.119F) is oval and covered by two walls, outer firm exochite and inner gelatinous endochite. Oogonia and antheridia are borne in unisexual conceptacles, those remain embedded in receptacles. The separated region grows and finally develops into a new individual like the mother. The male and female receptacles had indistinguishable shape in some cases; thus, an immature thallus is impossible to be identified. 11. Internal Structure 4. 3.117B). What is its function? Lamanaria 3 cell layers (medulla, cortex, meristoderm) Lithophyllum imitans. The paraphyses protrude out through the opening present on the outer side, the ostiole. 3.120C), then mitotic divisions and 8 nuclei are formed. 303_1.tifAdministrator iText 4.2.0 by 1T3XT 3.122). Vegetative reproduction : FRagmentation is the only known method of reproduction in the free floating species of sargassum. 3.120E). H��Wdc8M��O�뜇�����5/�*�; The conceptacle initial then undergoes mitotic division and by oblique septation it forms upper elongated tongue cell and lower broad basal cell (Fig. Features 5. Most of the species of Fucales reproduce sexually except Sargassum natans and Sargassum fluitans, which reproduce only by fragmentation (Lee, 2008).Reproduction is of oogamous type and reproductive structures in Fucales are borne in a special flask-like cavity, which is known as conceptacle. Plant Body of Sargassum 3. Later on only one penetrates the oogonial wall. Outer to the cavity, cortex is present; which consists of a few layers and thinner cells than axis and finally it ends with a single layered outer meristoderm. 3.119H). Like antheridium, oogonium also develops from the basal fertile layer of the conceptacle (Fig. But no matter how much money is forked out, the sargassum keeps coming. 3.120B). The oogonium in the conceptacle has cell walls that can be differentiated into a dense outer and a less dense inner microfibrillar layer. 12. The antherozoids and eggs i.e., the gametes, represent only the haploid (n) stage. 3.122). The antherozoids and eggs i.e., the gametes, represent only the haploid (n) stage. The eastern Pacific population has both male and female gametes on a single individual and is capable of self-fertilization. Thus it shows a typical example of diplontic life cycle. In West Africa, a part of Atlantic Ocean becomes densely occupied by Sargassum and the region is called as ‘Sargasso sea’. Sargassum. Reproduction 7. The cells are smaller in size than meristoderm. Sargassum vulgare C. 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