Page 94 - Algae Anatomy, Biochemistry, and Biotechnology

Anatomy 77

FIGURE 2.50 Root system of Fucus sp. (Heterokontophyta). AF, anterior flagellum; PF, posterior flagellum;
PR, proboscis root; BPR, bypassing microtubular root; MA, minor anterior root; MP, minor posterior root; DB,
deltoid band; SSB, strap-shaped band; and BSB, button-shaped band.

but perpendicularly to the rhizostyle. A microtubular root arises near the rhizostyle and passes
between the basal bodies in close association with the fibrous band, a second microtubular root
extends dorso-laterally in a curved path, and a third root, which can be very short, originates
near the rhizostyle and extends anteriorly. In addition to this rootlet, a conspicuous twelve-stranded
microtubular root is present in Chilomonas, together with a mitochondrion-associated lamella root,
while a delicated cross-banded anchoring fiber connecting one of the basal bodies to the ventral
groove is present in Cryptomonas. The striated components of the root system have been shown
to contain the contractile protein centrin (Figure 2.53).

Dinophyta
The root apparatus of these algae is quite complex for number and appearance of ancillary struc-
tures associated to the microtubular roots, and for the spatial relationship between roots and other
cell organelles. Minor features can be considered specie-specific, whereas major components are
common to almost all the dinoflagellates. The longitudinal basal body and the transverse basal
body are interconnected by a small striated connective band. A multimembered microtubular
root, the longitudinal root originates on left side of the longitudinal basal body and continues pos-
teriorly along the sulcus. A cross-striated fibrous root, the transverse striated root, emanates from
the left side of the transverse basal body and runs along the transverse flagellar canal and the cin-
gulum. Striated connectives link the transverse striated root to both the longitudinal root and the
longitudinal basal body, and the proximal portion of the longitudinal basal body to the longitudinal
root. The most distinct connective is a large electron-opaque fiber termed the nuclear fibrous