Term:
Placenta oblique
Placenta oblique
Definition:
A type of placentation in which the placenta is derived from a short, horizontally expanded lower septum that expands at a right angle to the upper septum and may be slightly upward and outward oriented at its end as seen in medial longitudinal section.
A type of placentation in which the placenta is derived from a short, horizontally expanded lower septum that expands at a right angle to the upper septum and may be slightly upward and outward oriented at its end as seen in medial longitudinal section.
Notes:
When viewed in cross section, each of the placentae in the adjacent in the adjacent locules of the 2-locular ovary appear like trees with the crowns on the outer end of the septum, a positions that contrasts with other placentation types in which the placentae are attached to the inner end of the septum. When the placentae of the adjacent locules are considered as a unit, they appear dumbbell-shaped, i.e., the two spreading "crowns" (the weights) are attached to one another by a handle. This type of placenta differs from all others by developing toward the outside of the locule; in contrast, other types Lecythidaceae develop at the apices of the septum. Oblique placentae are only found in the two clades of Eschweilera, i.e., the E. integrifolia and the E. parvifolia clades.
When viewed in cross section, each of the placentae in the adjacent in the adjacent locules of the 2-locular ovary appear like trees with the crowns on the outer end of the septum, a positions that contrasts with other placentation types in which the placentae are attached to the inner end of the septum. When the placentae of the adjacent locules are considered as a unit, they appear dumbbell-shaped, i.e., the two spreading "crowns" (the weights) are attached to one another by a handle. This type of placenta differs from all others by developing toward the outside of the locule; in contrast, other types Lecythidaceae develop at the apices of the septum. Oblique placentae are only found in the two clades of Eschweilera, i.e., the E. integrifolia and the E. parvifolia clades.