Placental unit

  • Title

    Placental unit

  • Definition

    The smallest continuous part of the placenta to which ovules are attached.

  • Notes

    In the Lecythidaceae, the placental unit consist of the expansion of the septa at their apices throughout the length of the placenta and is where the ovules are attached. Cross-sections and longitudinal sections have to be consulted to reveal the three dimensional structure of the placentae and its placental units. There are two placental units per locule, one developed from each end of the carpel that forms the walls of a locule. The placental unit is also equivalent to one-half of the placental end of each of the septae.

  • Related Terms

    Placenta (pl. = placentae)

    Septal unit

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