![]() ![]() ![]() Let's take a look at the kinds of plants that were common then. There were seed-bearing plants during the Pennsylvanian, but they were not similar to the modern ones. Spores thus differ from gametes, which are reproductive cells that must fuse in pairs in order to give rise to a new individual. Large trees existed, but they were not woody trees they were composed of thick bark with a central, pithy core. exospore endospore auxospore akinete anisospory spore, a reproductive cell capable of developing into a new individual without fusion with another reproductive cell. During the Pennsylvanina, the dominate plants were spore-bearing (they reproduced by spores, not seeds). The forests of the eastern United States today are dominated by seed-bearing woody trees, bushes and herbaceous plants. The plants of the Pennsylvanian were not like those of today. For more discussion about coal, see our section on coal information. The large number of coals in the coalfields is a result of these conditions coal is fossil peat, and peat is the accumulation of plant debris, and the abundance of plant debris results from the large lowland forests. If you look up pictures of non-flowering plants with their names. Unlike angiosperms, gymnosperms do not produce flowers or fruit. Spore-bearing plants are simple, or primitive, plants, for example mosses and ferns. Gymnosperms are abundant in temperate forest and boreal forest biomes with species that can tolerate moist or dry conditions. Their life cycles have two distinct generations. Some of the most recognizable examples of these woody shrubs and trees include pines, spruces, firs, and ginkgoes. The life cycle of spore-bearing plants varies significantly from the cycles of other common garden plants. ![]() Ferns and horsetail are well-known plants in this category today. Examples are the precursor cells of gametophytes of seed plants found in flowers (angiosperms) or cones (gymnosperms), and the zoospores produced from meiosis. The Pennsylvanian, for the eastern United States, was a time of tropical, humid climate and lush forests. Spore-bearing plants do not have true seeds, but instead reproduce through spores in alternating generations. The most abundant plant fossils in Kentucky are found in Pennsylvanian rocks in the State's two coal fields. ![]()
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