Solution:
The tetraspores are haploid cells that produce the haploid sexual plants which bear antheridia or oogonia on their germination. Such, type of life-cycle bears only two phases, i.e., diploid and haploid and is known as biphasic life-cycle. This type of alternation of generations is also known as isomorphic or homologous. The life-cycle of Ectocarpus, Ulva etc is also of isomorphic type, where the gametophyte and sporophyte are alike.
