Endosperm is an important source of nutrition in a human diet. An endosperm is the tissue produced inside the seeds of most flowering plants. It surrounds the embryo and provides nutrition in the form of starch, but also contains oils and protein. It is formed by the union of a sperm cell with two polar nuclei during double fertilization.
Some examples of endosperms are: corn (like those in the picture), popcorn, coconut “meat,” and coconut “water.”