Algae Anatomy, Biochemistry, and Biotechnology

12 Algae: Anatomy, Biochemistry, and Biotechnology
FIGURE 1.16 Cell division in Euglena sp. (Bar: 10 mm)
Algae exhibit three different life cycles with variation within different groups. The main difference
is the point where meiosis occurs and the type of cells it produces, and whether there is more
than one free-living stage in the life cycle.
Haplontic or Zygotic Life Cycle
This cycle is characterized by a single predominant haploid vegetative phase, with the meiosis
taking place upon germination of the zygote. Chlamydomonas (Chlorophyta) (Figure 1.19) exhibits
this type of life cycle.
FIGURE 1.17 Zoospores of Chlamydomonas sp. within the parental cell wall. (Bar: 10 mm)