Plant Evolution and Diversity Terms
Get down with the lingo
Alternation Of GenerationsA weird, funky lifestyle that all plants and some algae have. Each generation of plants alternates being haploid (n) or diploid (2n)—that is, every other generation has half the genetic information that the others have. Even though the plant only has half the genetic information, it can still make a whole plant. A sporophyte generation (2n) makes a gametophyte (n) plant that then makes a sporophyte, and this process goes on and on, generation after generation.
AngiospermA flowering plant. Yep, the ones with all the pretty petals and yummy fruits, like apples, cherries, and watermelon? Where's a fruit stand when you need one? Angiosperms are also the most common plant group on Earth.
ArchegoniumA structure where plant eggs are made. Think of it like a hen house for plants. The plural of archegonium is archegonia.
AntheridiumA structure where plant sperm are made. Antheridiums are found in nonflowering plants. The plural of antheridium is antheridia. Fancy, we know.
BryophyteA nonvascular plant. The bryophytes that are most familiar to people are the mosses. Bryophytes need to be tiny plants because they don’t have ways of transporting water and nutrients for long distances.
CotyledonA seed leaf. The cotyledons store nutrients inside the seed, and as a seed germinates, the cotyledons give those nutrients to the growing plant. The number of cotyledons is an important distinguishing factor between monocots and eudicots, so stay tuned for that.
CuticleA waxy layer of cells that covers a plant’s outer surface. (Wax: the stuff that helps skis slide through snow, surfboards glide over water, and…helps keep plants from drying out.)
DeciduousA characteristic of some plants that causes them to lose their leaves during the winter. A tree could "decide" to shed its leaves as a helpful way to remember the name; but in reality, the plant does not get to choose whether or not it sheds its leaves. Evolution already made that decision. Sorry.
DispersalThe process of moving spores, pollen, fruits, or seeds to colonize new places. The ancient Romans would be proud.
EudicotA member of a large group of flowering plants that is evolutionarily advanced.
EmbryophyteA plant that develops an embryo inside an enclosed space. This distinguishes "true plants" from algae.
EndospermA layer of tissue inside an angiosperm seed that acts as a food source for the embryo.
EphedrineA stimulant produced by plants in the genus Ephedra, which are commonly called Mormon Tea. Seriously, it is.
EquistemThe genus of plants called the horsetails. We’re not sure how close the resemblance to horses is, but the name stuck.
FiddleheadThe new, unfurled leaf of a fern. Not someone who is really into square dancing.
FrondA fern leaf.
GametophyteA plant that produces gametes (sperm and eggs).
GenusA group of species that are closely related. The plural of genus is genera.
GerminateThe process of sprouting roots and initial growth. For those of you obsessed with Purell, you're safe...for now.
GymnospermA group of seed plants whose seeds are not enclosed by an ovary or fruit. They may produce cones and do not have flowers. Gymnosperm shares the same root word as gymnastics and gymnasium, meaning "naked." Reading this definition and then showing up to gym class in your birthday suit is not what we had in mind. At all.
Herbaceous PlantA nonwoody plant that usually grows close to the ground.
HeterosporyThe condition of making two kinds of spores, female and male.
MacrofossilA fossil made from a plant part that is visible without a microscope, often a leaf or a root.
MicrofossilA microscopic fossil, usually pollen (male gametophyte). When wind-pollinated plants release their pollen, tons and tons (literally) of pollen grains float through the air, but only a few of them find eggs to fertilize. Many other pollen grains fall down to the ground in other places, and sometimes, the conditions are right to make them into fossils. Does the little pollen bit get to be a plant or a fossil? Only time will tell. What?
MonocotA type of flowering plant that only has one cotyledon and shares other characteristics, such as parallel leaf venation, adventitious roots, no secondary growth, and floral parts in multiples of threes. Monocot is short for "monocotyledon." Fancy.
Nonvascular PlantA plant without a system for transporting water and nutrients around its body. Similar to a building with no elevator.
OvuleThe part of a seed plant that produces the egg, and after fertilization, becomes the seed.
Parallel VenationThe pattern of veins in a monocot leaf. Veins run parallel to each other, instead of creating a big web—like they do in eudicot leaves. Though it sounds like a Silicon Valley buzzword, it is not.
PhloemA type of vascular tissue that transports sugars around the plant. Phloem flows from places where sugar is concentrated to where it is less concentrated. This tendency is called following a concentration gradient. Insert phlegm joke about boogers here.
PhylogeneticsThe analysis of DNA to study the evolutionary relationships between groups of organisms.
RhizoidA long bundle of cells that acts like a root for bryophytes, anchoring them to the ground. Does it creep anyone else out that these names are sounding more and more like parts of an alien colony from another planet? No? Okay then. Carry on with learning about (supposedly) innocuous plant life.
SphagnumA genus of moss that lives in peat bogs and forms peat, which can be used for fuel. If this term sounds like a dirty mind to you, you need to get your mind out of the gutter.
SporeA single haploid cell that contains the genetic information necessary to make a new plant.
SporophyteA spore-bearing plant; also the dominant plant type of ferns, gymnosperms, and angiosperms.
StrobilusThe reproductive structure of a gymnosperm. Also an excellent name for one of Frank Zappa's children.
TaxonomyThe classification of organisms into different levels of relatedness, such as phylum, family, or species.
ThallusA plant or algal body part that is not differentiated into roots, stems, and leaves. Also, rhymes with callous.
TracheophyteA plant with a vascular system. Plants do not have tracheas.
VascularA characteristics that relates to transport of water and nutrients in the plant body. Animals also have vascular systems. Plant-animal sharing time.
VicarianceThe division of an ancestral range due to a geographic barrier.
XylemThe water-conducting vascular tissue of a plant. Not…xylemophone.
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