Which statement correctly defines parietal placentation?

Which statement correctly defines parietal placentation?

• A. Ovules are positioned at the perimeter of the ovary
• B. Ovules are positioned on the central axis inside a multilocular ovary
• C. Ovules are attached to the base of the ovary
• D. Ovules are scattered within locules

Answer: (A)

Parietal placentation occurs when ovules are attached to the inner surface of the ovary wall along its outer perimeter, especially in a multilocular ovary. This means the placenta forms from the ovarian wall and the ovules line the edges or walls rather than aligning along a central axis or at the base. So describing ovules positioned at the perimeter of the ovary directly matches this pattern, making it the best description. Central axis attachment describes axile placentation, attachment at the base describes basal placentation, and scattered placement within locules refers to a different arrangement not characteristic of parietal placentation.

Parietal placentation occurs when ovules are attached to the inner surface of the ovary wall along its outer perimeter, especially in a multilocular ovary. This means the placenta forms from the ovarian wall and the ovules line the edges or walls rather than aligning along a central axis or at the base. So describing ovules positioned at the perimeter of the ovary directly matches this pattern, making it the best description. Central axis attachment describes axile placentation, attachment at the base describes basal placentation, and scattered placement within locules refers to a different arrangement not characteristic of parietal placentation.