seed plants
have seed plants (as the name implies), as seed dissemination organs. In contrast to the Cryptogams (Verbreitungsoragne: spores).
This distinction is then divided into two groups:
- angiosperm, seeds are wrapped entirely of carpels.
- gymnosperms, seeds are wrapped only in part from the carpels.
gymnosperms
The carpels are not completely closed. Gymnosperms are the original form, ie the angiosperms evolved from them.
The various flowers are asexual and consist solely of stamens (see illustration) or carpels. Often, several flowers of the same sex in journal summarized.
is the dissemination of pollen by the wind, with the possible pollination by insects. In this case, the seeds fall directly onto the unprotected site conception. In still other plants (Ginkopflanzen, cycads), there are sperm cells from the pollen tube into the cavity of the pollen chamber (filled with liquid) run from where they can swim to the egg. These
At current gymnosperms I eat to woody plants. The two main differences in comparison to the angiosperms are in the pathways (such as the liquid is transported in the plant) and in the fact that the angiosperms are fully enclosed by carpels (seed is spread through the fruit).
angiosperms (flowering plants)
The seeds are encased in an ovary (fruit leaves). He is the ovule in which there are the egg cells. If this develops a fertilized ovule of the ovary of a plant embryo (including the seeds). In the maturation, the ovary often developed for, pulp (eg, cherry).
are in the group of angiosperms there are differences in the flowers, the pathways, the components, den Befruchtungsmechanismen,... . Sie beinhaltet die meisten Arten.
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