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2. Stele (biology) - Wikipedia

   en.wikipedia.org/wiki/Stele_(biology)

   An endodermis generally surrounds the stele. A centrarch (protoxylem in the center of a metaxylem cylinder) haplostele is prevalent in members of the rhyniophyte grade, such as Rhynia. [6] actinostele – a variation of the protostele in which the core is lobed or fluted. [7] This stele is found in many species of club moss (Lycopodium and ...

3. Plant evolutionary developmental biology - Wikipedia

   en.wikipedia.org/wiki/Plant_evolutionary...

   The evolution of the MADS-box family has been extensively studied. These genes are present even in pteridophytes, but the spread and diversity is many times higher in angiosperms. [63] There appears to be quite a bit of pattern into how this family has evolved. Consider the evolution of the C-region gene AGAMOUS (AG).

4. Stellar evolution - Wikipedia

   en.wikipedia.org/wiki/Stellar_evolution

   Stellar evolution is the process by which a star changes over the course of its lifetime and how it can lead to the creation of a new star. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the current age of the ...

5. Pteridospermatophyta - Wikipedia

   en.wikipedia.org/wiki/Pteridospermatophyta

   Pteridospermatophyta, also called "pteridosperms" or "seed ferns" are a polyphyletic [1] grouping of extinct seed-producing plants.The earliest fossil evidence for plants of this type are the lyginopterids of late Devonian age. [2]

6. Pteridophyte - Wikipedia

   en.wikipedia.org/wiki/Pteridophyte

   A pteridophyte is a vascular plant (with xylem and phloem) that reproduces by means of spores. Because pteridophytes produce neither flowers nor seeds , they are sometimes referred to as " cryptogams ", meaning that their means of reproduction is hidden.

7. Timeline of plant evolution - Wikipedia

   en.wikipedia.org/wiki/Timeline_of_plant_evolution

   The evidence of plant evolution changes dramatically in the Ordovician with the first extensive appearance of embryophyte spores in the fossil record. The earliest terrestrial plants lived during the Middle Ordovician around 470 million years ago , based on their fossils found in the form of monads and spores, with resistant polymers in their ...

8. New HIV prevention drug could reach poorest countries ... - AOL

   www.aol.com/news/hiv-prevention-drug-could-reach...

   A new long-acting preventive HIV drug could reach the world’s poorest countries by the end of 2025 or early 2026, a global health official told Reuters on Tuesday. The ambition is to start ...

9. Lyginopteridales - Wikipedia

   en.wikipedia.org/wiki/Lyginopteridales

   The Lyginopteridales are an extinct group of seed plants known from the Paleozoic.They were the first plant fossils to be described as pteridosperms (a polyphyletic group sometimes referred to as "seed ferns") and, thus, the group on which the concept of pteridosperms was first developed; [2] they are the stratigraphically oldest-known pteridosperms, occurring first in late Devonian strata; [3 ...