Micrasterias

Micrasterias is a genus of uni-cellular green alga in the Desmidiales order.

Micrasterias is a eukaryotic, unicellular green alga that reaches ~0.35mm in size. Members have bilateral symmetry, with two semi-cells joined by a narrow isthmus containing the nuclei. Each semi-cell contains one large chloroplast, which is how many plants perform photosynthesis.

Micrasterias can reproduce sexually and asexually. Asexual reproduction is done through mitosis. When this occurs, genetic material of the parent is duplicated, and two small semi-cells grow between the original semi-cells, growing larger in size. Sexual reproduction occurs through conjugation, where two organisms come together and fuse their haploid cells to form a diploid zygote. The zygote usually forms a protective wall, which can allow the organism to stay dormant for several months in cold winters, and long droughts. When better conditions come, the zygospore will germinate, go through meiosis, and produce new haploid cells.

Species
See List of Micrasterias species