Prothallus (plural = prothalli)

  • Title

    Prothallus (plural = prothalli)

  • Definition

    The structure representing that part of a fern's life cycle between the germination of the haploid spore and the formation of the zygote. Fern prothalli are small, green, often heart-shaped, and bear the archegonia and antheridia where the egg and sperm are produced, respectively.This is the gametophyte generation of ferns and is completely independent of the sporophyte generation. Only those who know what they are looking for can find prothalli because they are small and hidden among the debris on the ground.

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