M-O Margin: The edge of a structure (leaf, petal, etc.). Midrib (midvein): The main, more prominent vein of a leaf. Monoecious: Male and female flower parts held in separate structures on the same plant. Naked (bud): A bud not covered by scales. Node: The point on a stem where the buds and leaves develop and are attached. Nut: large, dry fruit with a thick, bony wall surrounding the seed. Nutlet: A small nut. Opposite: Arranged in pairs; inserted on opposite sides of a stem at the same node. Ovary: The lower part of the female pistil. It contains the ovules that will become seeds when fertilized. Ovate: Egg-shaped, being broadest at the base. Ovule: The egg-containing structure held in the ovary. It becomes the seed when fertilized.