#dicots

Hello plant people! Here's a brief explanation of how monocots and dicots differ:

Where do the names come from?

You may be wondering how these taxon were named. Mono- and Di- are self explanatory -- one and two. But what about the -cot part? Well, the full names are Monocotyledons and Dicotyledons. A cotyledon is the embryonic leaf of the plant. Despite getting their names from this feature, it is not the most reliable way to characterize these since cotyledons are only present for a very short time in a plant's life. Here is a good picture of monocot vs dicot cotyledons:

By w:User:Pengo - Peter Halasz https://commons.wikimedia.org/w/index.php?curid=837422

Now, what are some other ways to differentiate the two?

Plant Life-Form -- Herbaceous vs Arboraceous (Woody)

Monocots are typically herbaceous, but can be arboraceous.

Dicots are commonly either herbaceous or arboraceous.

Pollen

Monocot pollen has only one furrow. AKA monocolpate:

Kleopatra -- https://commons.wikimedia.org/wiki/User:Kleopatra

Dicot pollen has three furrows. AKA tricolpate:

Marie Majaura

Flower

Monocots have trimerous flowers, meaning their flower structures (petals, septals, stamens, etc.) are in multiples of 3.

Dicots have tetramerous, flower structures in multiples of 4 or pentamerous, flower structures in multiples of 5.

Stem

Monocots have a hollow stem with scattered vascular bundles. They lack vascular cambium, which is the tissue that produces secondary growth, resulting in woody flesh.

Dicots have a non-hollow stem with a uniform ring of vascular bundles. They contain vascular cambium.

Leaf

Monocots have narrow, parallel-veined leaves with a sheathing base:

Dicots have broad leaves with a network of veins:

Root

Monocot roots are adventitious, meaning they develop wherever they can -- often in strange places. It's very cool! Here's a picture example:

Monocot roots briefly have a primary root, and then end up forming fibrous or fleshy root systems:

https://allen.in/neet/biology/fibrous-root

Dicots keep their primary root, which grows into a strong taproot. This taproot can grow small fibrous roots:

Taproots are often what we would call a vegetable!

https://www.britannica.com/topic/root-vegetable

Examples

Monocots:

Araceae "Arum"

Alismataceae "Water Plantain"

Liliaceae "Lily"

Ruscaceae "Butcher's Broom"

Orchidaceae "Orchid"

Dicots:

Fabaceae -- Beans

https://keys.lucidcentral.org/keys/v3/South_African_Plant_Families/key/South%20African%20Plant%20Families/Media/Html/Fabaceae.htm

Rubiaceae -- Coffee family!!!

Rosaceae -- Roses, Strawberries, Apples...

Geraniaceae -- Geranium family

By Alvesgaspar - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3565509

Asteraceae -- Sunflowers, Artichokes, Marigolds...

By Alvesgaspar, Tony Wills (10) - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3562701

References

Beautiful button orchid growing on a palm tree.

17/01/24 - Dischidia nummularia

Violet Wood Sorrel

Oxalis violacea

This beautiful oxalis violacea with showy, soft violet blooms is a perennial species native to the eastern and central United States.

May 12th, 2023

Jefferson County, Missouri, USA

Olivia R. Myers

A common lab plant that’s been poked and put under microscopes for decades may seem unlikely to keep secrets. But in widely studied Arabidopsis thaliana, scientists have identified the “cantil” — a newly reported plant organ named for its cantilever-like way of branching off of the main stem. The structure appears in only some A. thaliana and only under certain conditions, researchers report online June 15 in Development.

“If you told me of a new organ in a weird plant in Amazonia, I wouldn’t be surprised at all,” says François Parcy, a plant biologist at CNRS in Paris, who was not involved in the study. “What struck me is this happened in Arabidopsis. This is something that’s really surprising.”

Molecular biologist Timothy Gookin first suspected contamination or a mutation when he noticed some A. thaliana with odd stalks jutting out from the stem, like half-finished bridges. It took 12 years of experiments at Penn State to show that the rare stalks are a new type of plant part and to explain their trigger: delayed flowering.

Like many other plants, short days prompt A. thaliana, which is in the same family as cabbage and mustard greens, to shore up resources; long days tell it to churn out flowers. Cantils form when that transition from stockpiling to blooming is postponed, as the plant keeps growing while waiting for the flowering signal,

One of the books I’m currently reading. I’m taking notes from it into a bullet journal to avoid marking in the book, but I’ll still be able to keep notes separetly and compare to notes from more updated literature.

Copyright 1995 by Peter Loewer