The lifecycle of a Gymnosperm is a more complicated cycle than those of the Pteridophytes and Bryophytes species! The reasoning behind that is because of the advancements and evolved features this species of plants have made. During reproduction, the megasporangium in ovule undergoes meiosis which creates four haploid megastores. Of those four only one will ensure survival. From there that megaspore will develop into a female gametophyte. Just like in Pteridophytes and Bryophytes, the female gametophyte contains the archegonium which will produce the egg cell. Meanwhile, the microsporangia in the pollen cone will undergo meiosis to create haploid microspores. These microspores will develop into pollen grains or male gametophytes. These pollen gains contain the tube cell or pollen tube. The pollen is then carried to the seed cone by wind or animal. The tube cell forms the pollen tube through the micropyle or opening to reach the egg. Two sperm cells are created; one travels to fertilize the egg while the other sperm cell will end up dying off. After, fertilization the diploid zygote develops into an embryo, the remaining gametophyte will protect it and provide food. Once the sporophyte embryo is mature enough, the mature seed cone will open up into the wind when ideal conditions are right. The seed will then go through a process of seeding and turn into a large, mature sporophyte. The cycle then repeats.
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