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Life Cycle of Plants
 

This interactive model illustrates the life cycles of key groups of higher plants: mosses, ferns, gymnosperms and angiosperms. Use "Run", "Stop" and "Reset" buttons to control this animation. Choose the desired group of plants by using switch the appropriate buttons.

In mosses, the spermatozoid is passed to the female plant and fertilizes the egg cell, forming a zygote. The zygote, located inside the female organism, begins to divide while the spores are ripening inside of it. The wind carries the spores from the parent plant and, having landed in the soil, they grow to become a new organism.

In ferns, horsetails, and club mosses ripe sporangia, grouped into soruses on the lower sides of the leaves, burst, and let the spores be carried far and wide by the wind. Male gametophytes - the antheridia - also burst. The spermatozoids fertilize the archegonia forming a zygote, which then becomes a new plant.

Gymnosperm and angiosperm plants procreate with seeds. In gymnosperms, after male and female cones mature, the spores from the male cones land on female cones and fertilize the egg cells, which then become seeds. The wind carries the seeds away from the parent plant.

The most complicated system of procreation is that of the angiosperms. Their sex organs - stamens and pistils - are located in the flower (together or separately.) Pollen grows in the stamens. Insects or wind carry pollen to the stigma of the pistil. Pollen grains grow into the pistel through the style. Along this "tube" male gametes make their way towards the ovule, fertilizing the egg cell. After a while, a seed is formed. Once the seed reaches the ground, it grows through, giving rise to a new plant.

 
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