Some Specialized Leaves
Every seed contains one or more cotyledons, or seed leaves. Cotyledons digest the food stored in seeds and supply it to seedlings, nourishing them until the first true leaves appear. In some plants the cotyledons contain chlorophyll and make food by photosynthesis.
Bud scales are leaves that protect buds. The leaves of cacti and some other plants have developed into spines. Tendrils have developed from certain leaves in the sweet pea and a number of other plants. A leaf that grows at the base of a flower stalk, flower, or cluster of flowers is called a bract. In the dogwood, poinsettia, calla lily, and many other plants the bracts have developed into showy, flowerlike growths.
Cut leaves, placed in soil or some other medium, can be used to reproduce African violets, begonias, gloxinias, and certain other plants. Leaves of the Venus's flytrap, sundew, and pitcher plant trap insects and other small animals, which the plants use as food.