The photos are of Laminaria. It is recognizable through its holdfast structure, which help grip onto rocks. The body is made up of holdfast, stipe and blade. The tissues of Laminaria are differentiated, made up of medulla, cortex and epidermis. On the epidermis layer there is the sorus of sporangia, the reproductive organs. It consists of paraphysis, zoosporangium and zoospores inside. This structure only exists on the sporophyte stage of Laminaria.

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