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Life Cycle of a Fern
First posted Feb 14, 2004 Last
updated June 26, 2004
The life cycle of a fern is beautiful and complex,
but with a little study, you can understand it. Start
with number 1 below, the spore. This is like the seed
of a flowering plant, in that it is the way the fern
reproduces and spreads. A spore, however, is different
in that it is a single cell that has only one copy of
each chromosome (haploid), and a seed is multicellular
and has two (diploid). The spore develops into a plant
called a gametophyte that can produce both sperm and
eggs. These unite in the processes called fertilization,
producing a "baby" fern called a zygote, which
now has two copies of each chromosome (it is diploid).
By normal cell division, this grows into the fern as
we know it, the green leafy plant on the forest floor.
The fern produces the spore (still diploid), and the
cycle continues.
References
Campbell's Biology.
Acknowledgments
The illustration of the life cycle of the fern is
from the excellent book Biology, by
Campbell and Reece. It is a college text for beginning
biology students. I cannot recommend it highly enough.
If it has been a few years (!) since you have had biology,
you will not believe how much things have changed. Not
only is there a lot more known about biology, the presentation
of the material is vastly improved. From text that is
closer to literature than dry explanation, to color
illustrations and color photographs that are so widely
used, I doubt that in its entire 1240 pages, there are
any without at least three or more color graphics of
some sort. And that does not even begin to explore the
enclosed CD or associated online material. I will eat
my hat if you don't love the book. I bought mine online,
at Amazon.com:
Campbell's Biology.
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