Monocot vs Dicot – How to Tell the Difference


Monocot vs Dicot
Monocots and dicots are the two main types of flowering plants.

Monocots and dicots are the two broad groups of flowering plants or angiosperms. Historically, scientists classified plants as monocots or dicots based on distinct differences between them. In modern times, molecular biology and genetics indicate the dicots are not all that similar to each other. Even so, most scientists still classify plants as either monocots or dicots. Here are the differences between monocots and dicots and examples of each group.

Monocots

Examples of Monocots
Examples of monocots include grasses, grains, palms, daffodils, and orchids.

Monocots (or monocotyledons) are plants which have seed with one cotyledon. When the seed germinates, the embryo has one seed leaf. There are around 65,000 species of monocots. Examples of monocots include grasses, grains, onions, daffodils, coconuts, and orchids. Monocot flowers have three petals or else the flowering parts are in multiples of threes. These plants have fibrous (adventitious) roots. The leaves have stomata in rows on both leaf surfaces and veins that run parallel to each other. The upper surface of some monocot leaves have bulliform cells, which control water loss. Each pollen grain has a single pore or furrow. In the stem, the xylem and phloem vascular bundles are scattered, but they form a ring in the roots.

Dicots

Examples of Dicots
Examples of dicots include beans, daisies, mint, apples, and maples.

A dicot (or dicotyledon) has seeds which have two cotyledons. The plant embryo has two seed leaves, which differ in appearance from the mature leaves. Dicots are much more abundant than monocots. Approximately 250,000 species of dicots are known. Examples of dicots include beans, peas, carrots, apples, roses, dandelions, daisies, cacti, oaks, and maples. Dicot flowering parts are in multiples of four or five. The plant roots often are taproots. The leaves often have stomata on only one surface (usually the lower one) and branched veins. Each pollen grain has three pores or furrows. In the stem, the xylem and phloem vascular bundles form a ring. In the roots, the xylem is central (often forming an “x” shape), with the phloem between the arms of the xylem. Dicot plants often send out secondary growth, while monocots do not.

Monocots vs Dicots – Summary of Differences

Here is a summary of the differences between monocots and dicots:

MonocotsDicots
Seed1 cotyledon2 cotyledons
RootFibrousTaproot
LeafVeins are parallelVeins are branched
Root vascular bundles (xylem and phloem)Xylem and phloem in a ringRoot phloem between xylem arms
Stem vascular bundles (xylem and phloem)Scattered throughout stemArranged in a ring
Leaf stomataStomata on upper and lower surfacesStomata often on one surface (usually lower)
Secondary growthAbsentOften present
Pollen1 pore or furrow3 pores or furrows
FlowerPetals in multiples of 3Petals in multiples of 4 or 5
ExamplesGrasses, corn, grains, lilies, onions, carrots, coconut, daffodils, orchidsBeans, coffee, daisies, maple, tomato, mint, cactus

References

  • Angiosperm Phylogeny Group (2016). “An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV”. Botanical Journal of the Linnean Society. 181 (1): 1–20. doi:10.1111/boj.12385
  • Bell, Adrian D. (2008) [1991]. Plant Form. An illustrated guide to flowering plant morphology. Oxford University Press. ISBN 9780881928501.
  • Bessey, Charles E. (1915). “The phylogenetic taxonomy of flowering plants”. Annals of the Missouri Botanical Garden. 2 (1/2): 109–164. doi:10.2307/2990030
  • Cronquist, Arthur (1981). An integrated system of classification of flowering plants. New York: Columbia University Press. ISBN 978-0-231-03880-5.
  • Datta, Subhash Chandra (1988). Systematic Botany (4th ed.). New Delhi: New Age Intl. ISBN 81-224-0013-2.