5/15/2023 0 Comments Binary fission example![]() This is termed as zygotic meiosis, in which only zygote is diploid but rest of the life cycle is haploid. This is called gametic meiosis, in which gametes become haploid.īut in some protozoans reduction division occurs in one of the subsequent divisions after formation of zygote. In majority, reduction division occurs shortly before syngamy. Sexual reproduction involves meiotic division reducing the chromosomes to haploid number. ![]() However, there are many protozoans in which sexual reproduction is of regular occurrence. ![]() Most protists (protozoa) can continue to live, multiplying asexually for prolonged periods and may undergo sexual reproduction only at irregular intervals. The two units (male and female gametes) from two separate individuals unite by fusion of their cytoplasm, followed by the union of their nuclei. The modes of reproduction in which two gametes unite to form a new individual is known as sexual reproduction. It may be simple or multiple, exogenous or endogenous. New individuals are produced by separation of a portion of the cytoplasm of the parent organism with a daughter nucleus. The daughter individuals regain the normal size and the number of nuclei is restored by further nuclear division. The multinucleate individual divides into many small multinucleate offspring’s by simple division of cytoplasm independent of nuclear division. Motile spores are known as swarmer’s or swarmospores. ![]() The products are surrounded by a cyst or a resistant covering and termed as spores. The resulting individuals are known as agametes or merozoites. ![]()
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