Page 60 - Algae Anatomy, Biochemistry, and Biotechnology
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Anatomy 43
FIGURE 2.10 Triceratium sp., a centric diatom.
There are two types of portules: fultoportulae (Figure 2.12) found only in the order Thalassiosirales
and rimoportulae (Figure 2.13), which are universal. The structure of the fultoportulae is an external
opening on the surface of the valve extended or not into a protruding structure (Figure 2.12). The
other end penetrates the silica matrix and is supported with two to five satellite pores. The portules
FIGURE 2.11 Rhoicosphenia sp., a pennate diatom.