TYPICAL PLANT LIFE CYCLE
The life cycle of each different type of plant differs depending on the category. The one pictured one the right is the general and typical life cycle of a plant. Plant life cycles generally switch between two different phases: a diploid (2n) stage, and a haploid (n) stage. This switch is often called alternation of generations. Throughout the cycle, meiosis and mitosis alternate in order to make gametes and spores, the two reproductive cell types. The diploid stage is known as the sporophyte stage, while the haploid stage is known as the gametophyte stage. Spores are haploid, and are basically the reproductive cells formed in the sporophyte plant by meiosis. These eventually will grow into brand new individuals, known as the gametophytes. The gametes are the reproductive cells formed by mitosis, and by connecting with another gamete during fertilization, they form a new diploid sporophyte. The earliest plants, such as bryophytes and pteridophytes, require water for reproduction. On the other hand, recent seed plants can reproduce without water, while many other plants use vegetative or asexual reproduction. |