Life cycle to the series of changes that an organism undergoes through its lifetime. Lifecycles can be haploid, diploid or alternating between the two and may either be haplontic, diplontic or haplodiplontic. In case of haplontic life cycle, the haploid stage is multicellular but the diploid stage is single celled. Spirogyra shows haplontic life cycle.
Ectocarpus exhibits Haplo-diplontic life-cycle pattern.
Fucus and Cycas exhibits diplontic life-cycle pattern.