Characteristics of Monocot Flower Embryos

Single Cotyledon

• The determining factor in whether or not a plant is a monocot or dicot is the number of cotyledons, also known as "seed leaves," found in the embryo, according to the University of California Museum of Paleontology. Cotyledons are the young "seed leaves" that transfer nutrients stored in the seed to the young plant embryo until the seedling sprouts its first true leaves and is able to perform photosynthesis. Monocot flower embryos almost always produce a single cotyledon while dicot embryos produce two; hence the names of the two classes of angiosperms: the Monocotyledonae, meaning "one cotyledon," and the Dicotyledonae, meaning "two cotyledons."

Scutellum

• The single seed leaf produced by monocot embryos, sometimes called a scutellum, looks different than the pair that dicots produce. It is usually thin, long and narrow, and resembles the plant's adult leaves greatly, as they don't contain the nutrient-rich endosperm for the embryo. Dicot seed leaves differ, as they are often fatter and a different shape than the plant's true adult leaves because they store the endosperm which feeds the seedling. The leaf veins of monocot embryos typically run in straight lines up and down, though they sometimes run parallel from the leaf's center to its edge.

Coleoptile

• Monocots produce a coleoptile, a thin sheath that houses the stem and leaves above the scutellum, known as the plumule. The coleoptile protects the young embryo while it grows, helping ensure it fully develops before emerges from the soil.

Other Characteristics

• The University of California Museum of Paleontology notes that as a young seedling and mature plant, there are a number of characteristics that distinguish monocots from dicots. Plants considered monocots typically exhibit flower parts in multiples of three, rather than multiples of four or five as with dicots, pollen with a single pore, where dicots develop pollen with three pores, and adventitious roots, rather than roots that develop from a radicle, as in dicots. Secondary growth is typically absent in monocot specimens, while plants considered dicots often produce secondary growth.