1. in the Proterozoic era, precise aerobic organisms (cyanobacteria and green algae) are widespread;
2. the formation of a soil substrate on land at the end of the Silurian period;
3. the emergence of multicellularity, which makes possible the specialization of cells within one organism;
4. land development by psilophytes;
5. from psilophytes in the Devonian period a whole group of terrestrial plants arose – mosses, lycopods, horsetails, ferns, which reproduce by spores;
6. Gymnosperms originated from seed ferns in the Devonian. The emerging structures necessary for seed reproduction (for example, the pollen tube) freed the reproductive process in plants from dependence on the aquatic environment. Evolution followed the path of reduction of the haploid gametophyte and the predominance of the diploid sporophyte;
7. The Carboniferous period of the Paleozoic era is distinguished by a large variety of terrestrial vegetation. Treelike ferns have spread, forming coal forests;
8.in the Permian period, ancient gymnosperms became
the dominant group of plants, in connection with the appearance of an arid climate, giant ferns, tree-like lyres disappear;
9. in the Cretaceous period, the flowering of angiosperms begins, continuing to this day.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.