Algae plants are simple in structure and have no differentiation of roots, stems and leaves. Spirogyra and kelp belong to algae plants. Bryophytes have no real roots and cannot support the aboveground parts of the highlands. Although they have stems and leaves, there is no transport tissue in them, so they can't transport a lot of nutrients for plants to use. Therefore, bryophytes are relatively short, such as cucurbitaceae and Phragmites. With the differentiation of roots, stems and leaves, ferns can absorb a lot of water and inorganic salts, and have transport tissues in their bodies, which can transport a lot of nutrients for plants.

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