32
Algae
are embedded within the chloroplast and often penetrated by thylakoids. The circular molecules of
chloroplast DNA are concentrated in numerous small blobs (1–2 μm in diameter). The most important reserve polysaccharide is starch, which occurs as grains inside the chloroplasts; glucan or β-1,4
mannan can be present in the cell wall of some Ulvophyceae. Eyespot, if present, is located inside
the chloroplast and consists of a layer of carotenoid-containing lipid droplets between the chloroplast envelope and the outermost thylakoids.
charophyTa
Charophytes are the organisms most closely related to land plants. The six groups of the phylum have been distinctly recognized on the basis of ultrastructural, biochemical, and molecular
data. Mesostigmatophyceae (Figure 1.1v) and Chlorokybophyceae form the earliest branching
FIGURE 1.42 Thallus of Trentepohlia arborum.
FIGURE 1.43 Group of Chlorella sp. cells. Scale bar: 10 μm.
Algae
are embedded within the chloroplast and often penetrated by thylakoids. The circular molecules of
chloroplast DNA are concentrated in numerous small blobs (1–2 μm in diameter). The most important reserve polysaccharide is starch, which occurs as grains inside the chloroplasts; glucan or β-1,4
mannan can be present in the cell wall of some Ulvophyceae. Eyespot, if present, is located inside
the chloroplast and consists of a layer of carotenoid-containing lipid droplets between the chloroplast envelope and the outermost thylakoids.
charophyTa
Charophytes are the organisms most closely related to land plants. The six groups of the phylum have been distinctly recognized on the basis of ultrastructural, biochemical, and molecular
data. Mesostigmatophyceae (Figure 1.1v) and Chlorokybophyceae form the earliest branching
FIGURE 1.42 Thallus of Trentepohlia arborum.
FIGURE 1.43 Group of Chlorella sp. cells. Scale bar: 10 μm.