In summary, the diploid phase of the animal life cycle can be said to be the dominant phase, with the gametes being the only haploid elements. Specific cells in the mature diploid phase of the plant life cycle undergo meiosis, but this does NOT produce gametes. Instead, the haploid cells are known as spores . Meiosis in plants does not produce gametes, but rather spores. In all but the simplest aquatic plants, the spore developes into a multicellular haploid plant known as the gametophyte .
Spores typically develop into multicellular, haploid gametophytes.
Since the gametophytes are already haploid, the gametes are produced by mitosis , not meiosis. The nature of plant gametes is quite variable compared to animals. Although the gametes appear identical, there are subtle genetic or physiological differences known as mating types. Anisogamy is also typical of some algae. The condition is known as oogamy and resembles the situation in animals only as a result of evolutionary convergence - a topic that will be discussed in class.