Cotyledon.
The leaves contained in the seed which are the first to appear when a seedling germinates; they are different from those that follow. Plants are classified according to whether there are one or two.
The leaves contained in the seed which are the first to appear when a seedling germinates; they are different from those that follow. The flowering plants are subdivided into 2 major classes, the monocotyledons and dicotyledons, according to whether they have one or two seed leaves.