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Like nonvascular plants, the sperm
of the vascular seedless plants
must swim to the egg. However
unlike nonvascular plants, in
vascular seedless plants, it is the
sporophyte that is dominant. If
you have ever admired a fern in Figure 11 – The “wing” shape of the maple
someone’s yard, the plant you are leaf inspired engineers.
admiring is a sporophyte.
Another common strategy for seed
Seed Dispersal dispersal is the development of
fruit. Fruit is meant to be tasty to
If a plant has seeds, the seeds animals. The animal takes the fruit
must be dispersed, or spread out. from a tree in one location and
If is helpful for a plant to spread its eats it as it walks.
seeds out as far as possible, so
that its offspring can spread in At some point, the animal either
many areas and not compete with drops the seeds onto the ground (if
each other for resources. Plants they are not edible) or releases
have developed many ways to them in its feces (if they are
make sure their seeds are spread edible.)
out.
Either way, the seeds come out
Some plants allow the wind to and are now a pretty good distance
carry their seeds. If you’ve ever away from the parent plant. When
blown on the puff of a dandelion, we think of fruit, we think of things
you’ve seen an example of this. we can eat, but burrs are actually
Some other plants, including pine also fruit. These structures are
and maple, have seeds with wing- designed to stick to animal’s fur,
like structures on the bottom to and be just annoying enough that
help them travel in the wind. the animal scratches them off
some distance from the parent
tree. If you’ve ever gone hiking,
you might have found a burr in
your sock. Who knows, maybe you
even helped a plant reproduce.
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