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Leaves and stem
Although
ferns are generally bracketed along with horsetails and club
mosses, the leaves of the fern and those of horsetails and club
mosses are different. Ferns have large compound leaves. They are
complexly veined fronds, which are more closely related to the
leaves of the seed-bearing vascular plants. Whereas, those of
horsetails and club mosses are scale like, with one-veined leaves.
The leaves of the fern uncurl in a typical fashion during spring.
All
fern stems come from underground rhizomes (subterranean plant stem
that is thickened by deposits of reserve food material and which
produce shoots above and roots below). The spores of the most
common species may be found in rows on the underside of the
leaves.
Reproduction
Ferns,
club mosses and horsetails reproduce in a similar way. There is an
alternation of generations. Morphologically, the life cycle may be
divided into two phases – sporophyte and gametophyte. The
sporophyte generation is the mature, fronded form. It is the spore
bearing plant of ferns and its cousins and is also the largest and
most obvious stage in the fern’s life cycle.
The
plants that bear reproduction cells, known as gametes, are small
and tiny and they are called gametophy. They resemble a moss or
liverwort. This generation begins with the germination of a spore,
a single microscopic cell produced by a mature sporophyte. The
spores of a mature fern are contained in cases called sporangia
found on the leaves of the plant. Generally, spores are carried
and scattered by the wind. When the spores germinate, they produce
tiny heart or ribbon shaped structures that possess a single set
of chromosomes.
Uses
Ferns are used as indoor plants. Another use of the fern is
the ether that is extracted from the rhizomes of the male fern.
Veterinary doctors use it to get rid of parasitic worms.
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