Thinking Citizen Blog — Monocots vs Dicots: Flowers, Roots, Leaves, Stems — Who Cares? Who Should?
Thinking Citizen Blog — Wednesday is Climate Change, the Environment, and Sustainability Day
Today’s Topic: Monocots vs Dicots: Flowers, Roots, Leaves, Stems — Who Cares? Who Should?
What’s a cot, anyway? Short for cotyledon which is an embryonic leaf in a flowering plant. Some flowering plants have two (dicot), others have one (monocot). Monocots include humble grasses (the most economically important) and exotic orchids (the largest family by number of species with 20,000 out of 60,000 for all monocots). Wheat, rice, bananas, ginger, asparagus — all monocots. So are most bulbous plants — like tulips, lilies, and daffodils. There are 3X as many dicots as monocots — about 180,000 species. Most garden plants, trees, and shrubs are dicots. Think oaks, maples, roses, geraniums. And then there are plants that are neither dicots nor monocots — like conifers, ferns, mosses, gingkos. These are gymnosperms, non-flowering plants. For reference, there are about 300,000 species of angiosperms but only 1000 species of gymnosperms. So how can you tell a monocot from a dicot? Today, four distinguishing traits: flowers, roots, leaves, and stems. Experts — please chime in. Correct, elaborate, elucidate.
FLOWER PETALS: multiples of three (monocots) versus multiples of four or five (dicots)
1. Ever counted the petals on a tulip or an iris?
2. How about a dogwood or a crab apple?
3. How about a rose?
NB: Highly recommended. Math can be so much fun. And so aesthetically rewarding.
STEMS: flexible (monocots) versus woody (dicots)
1. No concentric rings in monocots.
2. Although monocot stems are usually flexible, not the case with bamboo and palms.
3. Monocot stems are hollow.
NB: Monocots are usually short-lived and don’t need secondary growth. “They complete their cycle within a year in annuals and with in two years in biannual .No need to develop secondary vascular tissues and periderm. Perennials are rare in Monocots. Cocconut and palm are few plants undergoes secondary growth.”
ROOTS: fibrous (monocot) versus one big tap root (monocot)
1. Fibrous = wide network of thin roots.
2. Tap root = single thick root that goes deep with smaller, lateral branches.
3. “The outside of both monocot and dicot roots is covered with a series of hair-like protrusions, appropriately called root hairs. They maximize the root’s water and mineral absorption capabilities because they increase its surface area. The epidermis made up of dermal tissue, is the outermost layer of the root. Like the epidermis of human skin, the root’s epidermis is protective, preventing damage to the root.
LEAVES: parallel veins and narrow leaf (monocot) versus branched and broad (dicot)
1. Dicot leaves can be feather-like in their veins (“pinnated”) or palmate (like the palm of the hand).
2. Dicots have stomata (pores critical to exchange of gases) on just the underside of the leaf whereas monocots have stomata on both sides.
3. “Both monocot and dicot leaves have an outer, waxy layer called the cuticle that covers the dermal tissue of the upper and lower epidermis. The cuticle protects the leaf and helps it retain water. The epidermis, which is located beneath the cuticle, also protects the leaf.”
Monocotyledons vs Dicotyledons
dicotyledon | Definition, Examples, & Facts
Differences Between Monocot And Dicot Stem in Tabular Form
Why is cambium absent in monocots?
ATTACHMENTS BELOW:
#1 A graphic guide to justice (9 metaphors on one page).
#2 “39 Songs, Prayers, and Poems: the Keys to the Hearts of Seven Billion People” — Adams House Senior Common Room Presentation, 11/17/20
Here is a link to the last four years of posts organized by theme: (including the book on foreign policy)
PDF with headlines — Google Drive
YOUR TURN
Please share the coolest thing you learned in the last week related to climate change or the environment. Or the coolest, most important thing you learned in your life related to climate change that the rest of us may have missed. Your favorite chart or table perhaps…
This is your chance to make some one’s day. Or to cement in your own mind something that you might otherwise forget. Or to think more deeply than otherwise about something dear to your heart.
