Seed Structure and Early Development of the Sporophyte

Seeds develop from fertilized flowers. Specifically, seeds develop from ovules found in the ovary of the flower, through a process called double fertilization. During this process, one sperm fertilizes the egg and one sperm fertilizes the two polar nuclei, resulting in a sporophyte embryo and an endosperm—a store of nutrients.  

The sporophyte embryo has a double set of chromosomes, one set from each parent, formed by the fertilization of a haploid egg by a haploid sperm. 

The embryo consists of the precursor tissue for stems and roots, as well as one or more embryonic leaves—called cotyledons. The embryo is surrounded by a food reserve in the form of an endosperm, cotyledons, or both, and is enclosed within a protective seed coat to form a seed. 

Plants are generally classified as monocot or dicot, depending on the number of cotyledons in their seeds. 

Typically, monocot seeds have a single large cotyledon called the scutellum. During germination, the scutellum absorbs enzymatically-released food materials from the endosperm and transports them to the developing embryo. 

Dicot seeds, by contrast, have two fleshy cotyledons. Many mature dicot seeds lack endosperm and reserve food m