Definition of alternation of generations in English:

alternation of generations


  • A pattern of reproduction occurring in the life cycles of many lower plants and some invertebrates, involving a regular alternation between two distinct forms. The generations are alternately sexual and asexual (as in ferns) or dioecious and parthenogenetic (as in some jellyfish)

    • ‘Like plants and many protists, brown algae undergo a complex life cycle involving alternation of generations.’
    • ‘Although they are often unicelled and simple, some algae have a 1n - 2n life cycle which constitutes an alternation of generations.’
    • ‘In many organisms with both sexual and asexual reproduction, including most sexual protists, fungi, algae, and nonseed plants, sex involves an alternation of generations between haploid and diploid phases.’
    • ‘Cnidarians show an alternation of generations in which two body forms, the polyp and the medusa, alternate.’
    • ‘In an alternation of generations the other phase produces a brownish gall on cedars.’