Talk about digenetic cycle of algae *heteromorphic*

Laminaria exhibits an alternation of heteromorphic generations. The sporophyte plant is a large multicellular alga whereas the microscopic female and male gametophytes are composed of few cells. The sporophyte generation (2n) develops on the surface of its blades sori containing sporangia and paraphyses; sporangia produce by meiosis motile flagellated zoospores (n ch), which develop into male and female gametophytes (n ch). Male gametophytes release motile male gametes. Female gametophytes produce eggs which remain attached to it. Male gametes fertilize the eggs; the fertilization of Laminaria is oogamous.