Indiana Nature Biology Glossary

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Oblong Leaf: A leaf that is broadly oval-shaped, much longer than it is wide, and with parallel or nearly parallel sides.

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Oligophagous: In zoology, an organism whose diet is limited to a narrow range of food sources. With insects and other invertebrates, the term usually applies to those organisms that feed on multiple members of the same plant family.

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Opposite Leaves: An arrangement of leaves and buds that are not alternating one another but rather occur in pairs, usually on opposite sides of the branch.

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Organism: A complete individual living thing. Examples include animals, plants, fungi, protists, bacteria, and other life forms.

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Outer Margin: The edge of an insect’s wing that is the farthest from the body.

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Oval Leaf: An elliptical-shaped leaf that is broadest in the middle, whose width is typically more than half its length, and tapers to small or no points.

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Ovary: The typically enlarged lower portion of the pistil that contains the ovule(s) and later the fruit.

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Ovate Leaf: A broad, egg-shaped leaf whose widest point is below the middle.

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