Page 29 - Algae
P. 29

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 differ-
                  ence 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)
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