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How do enzymes release stored nutrients for a growing seedling?

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Cluster of bright red seeds emerging from the cone-shaped fruit of a magnolia grandiflora, surrounded by large, glossy green leaves. — seed Fruit and seeds of the southern magnolia (*Magnolia grandiflora*). The fruit is an aggregate of follicles, and each follicle bears a single red seed.

To support a growing seedling before it becomes nutritionally self-supporting, the plant must mobilize energy reserves—such as starch, proteins, and lipids—that are stored in an insoluble form within the seed.

Because these materials cannot be used directly by the developing embryo, the seedling relies on enzymes to break them down into soluble, transportable forms. These enzymes are secreted by the embryo itself or, in some cases, by specialized cells within the endosperm.12

For example, in many monocots like grasses, the cotyledon is modified into an enzyme-secreting structure called the scutellum. This organ acts as a bridge between the embryo and the nutrient-rich endosperm, digesting the stored reserves and facilitating the delivery of nutrients to the active areas of the growing plant. Once these reserves are mobilized, the products are translocated to the radicle and shoot to fuel further growth and development.21