- •Contents
- •Preface to the first edition
- •Flagella
- •Cell walls and mucilages
- •Plastids
- •Mitochondria and peroxisomes
- •Division of chloroplasts and mitochondria
- •Storage products
- •Contractile vacuoles
- •Nutrition
- •Gene sequencing and algal systematics
- •Classification
- •Algae and the fossil record
- •REFERENCES
- •CYANOPHYCEAE
- •Morphology
- •Cell wall and gliding
- •Pili and twitching
- •Sheaths
- •Protoplasmic structure
- •Gas vacuoles
- •Pigments and photosynthesis
- •Akinetes
- •Heterocysts
- •Nitrogen fixation
- •Asexual reproduction
- •Growth and metabolism
- •Lack of feedback control of enzyme biosynthesis
- •Symbiosis
- •Extracellular associations
- •Ecology of cyanobacteria
- •Freshwater environment
- •Terrestrial environment
- •Adaption to silting and salinity
- •Cyanotoxins
- •Cyanobacteria and the quality of drinking water
- •Utilization of cyanobacteria as food
- •Cyanophages
- •Secretion of antibiotics and siderophores
- •Calcium carbonate deposition and fossil record
- •Chroococcales
- •Classification
- •Oscillatoriales
- •Nostocales
- •REFERENCES
- •REFERENCES
- •REFERENCES
- •RHODOPHYCEAE
- •Cell structure
- •Cell walls
- •Chloroplasts and storage products
- •Pit connections
- •Calcification
- •Secretory cells
- •Iridescence
- •Epiphytes and parasites
- •Defense mechanisms of the red algae
- •Commercial utilization of red algal mucilages
- •Reproductive structures
- •Carpogonium
- •Spermatium
- •Fertilization
- •Meiosporangia and meiospores
- •Asexual spores
- •Spore motility
- •Classification
- •Cyanidiales
- •Porphyridiales
- •Bangiales
- •Acrochaetiales
- •Batrachospermales
- •Nemaliales
- •Corallinales
- •Gelidiales
- •Gracilariales
- •Ceramiales
- •REFERENCES
- •Cell structure
- •Phototaxis and eyespots
- •Asexual reproduction
- •Sexual reproduction
- •Classification
- •Position of flagella in cells
- •Flagellar roots
- •Multilayered structure
- •Occurrence of scales or a wall on the motile cells
- •Cell division
- •Superoxide dismutase
- •Prasinophyceae
- •Charophyceae
- •Classification
- •Klebsormidiales
- •Zygnematales
- •Coleochaetales
- •Charales
- •Ulvophyceae
- •Classification
- •Ulotrichales
- •Ulvales
- •Cladophorales
- •Dasycladales
- •Caulerpales
- •Siphonocladales
- •Chlorophyceae
- •Classification
- •Volvocales
- •Tetrasporales
- •Prasiolales
- •Chlorellales
- •Trebouxiales
- •Sphaeropleales
- •Chlorosarcinales
- •Chaetophorales
- •Oedogoniales
- •REFERENCES
- •REFERENCES
- •EUGLENOPHYCEAE
- •Nucleus and nuclear division
- •Eyespot, paraflagellar swelling, and phototaxis
- •Muciferous bodies and extracellular structures
- •Chloroplasts and storage products
- •Nutrition
- •Classification
- •Heteronematales
- •Eutreptiales
- •Euglenales
- •REFERENCES
- •DINOPHYCEAE
- •Cell structure
- •Theca
- •Scales
- •Flagella
- •Pusule
- •Chloroplasts and pigments
- •Phototaxis and eyespots
- •Nucleus
- •Projectiles
- •Accumulation body
- •Resting spores or cysts or hypnospores and fossil Dinophyceae
- •Toxins
- •Dinoflagellates and oil and coal deposits
- •Bioluminescence
- •Rhythms
- •Heterotrophic dinoflagellates
- •Direct engulfment of prey
- •Peduncle feeding
- •Symbiotic dinoflagellates
- •Classification
- •Prorocentrales
- •Dinophysiales
- •Peridiniales
- •Gymnodiniales
- •REFERENCES
- •REFERENCES
- •Chlorarachniophyta
- •REFERENCES
- •CRYPTOPHYCEAE
- •Cell structure
- •Ecology
- •Symbiotic associations
- •Classification
- •Goniomonadales
- •Cryptomonadales
- •Chroomonadales
- •REFERENCES
- •CHRYSOPHYCEAE
- •Cell structure
- •Flagella and eyespot
- •Internal organelles
- •Extracellular deposits
- •Statospores
- •Nutrition
- •Ecology
- •Classification
- •Chromulinales
- •Parmales
- •Chrysomeridales
- •REFERENCES
- •SYNUROPHYCEAE
- •Classification
- •REFERENCES
- •EUSTIGMATOPHYCEAE
- •REFERENCES
- •PINGUIOPHYCEAE
- •REFERENCES
- •DICTYOCHOPHYCEAE
- •Classification
- •Rhizochromulinales
- •Pedinellales
- •Dictyocales
- •REFERENCES
- •PELAGOPHYCEAE
- •REFERENCES
- •BOLIDOPHYCEAE
- •REFERENCE
- •BACILLARIOPHYCEAE
- •Cell structure
- •Cell wall
- •Cell division and the formation of the new wall
- •Extracellular mucilage, biolfouling, and gliding
- •Motility
- •Plastids and storage products
- •Resting spores and resting cells
- •Auxospores
- •Rhythmic phenomena
- •Physiology
- •Chemical defense against predation
- •Ecology
- •Marine environment
- •Freshwater environment
- •Fossil diatoms
- •Classification
- •Biddulphiales
- •Bacillariales
- •REFERENCES
- •RAPHIDOPHYCEAE
- •REFERENCES
- •XANTHOPHYCEAE
- •Cell structure
- •Cell wall
- •Chloroplasts and food reserves
- •Asexual reproduction
- •Sexual reproduction
- •Mischococcales
- •Tribonematales
- •Botrydiales
- •Vaucheriales
- •REFERENCES
- •PHAEOTHAMNIOPHYCEAE
- •REFERENCES
- •PHAEOPHYCEAE
- •Cell structure
- •Cell walls
- •Flagella and eyespot
- •Chloroplasts and photosynthesis
- •Phlorotannins and physodes
- •Life history
- •Classification
- •Dictyotales
- •Sphacelariales
- •Cutleriales
- •Desmarestiales
- •Ectocarpales
- •Laminariales
- •Fucales
- •REFERENCES
- •PRYMNESIOPHYCEAE
- •Cell structure
- •Flagella
- •Haptonema
- •Chloroplasts
- •Other cytoplasmic structures
- •Scales and coccoliths
- •Toxins
- •Classification
- •Prymnesiales
- •Pavlovales
- •REFERENCES
- •Toxic algae
- •Toxic algae and the end-Permian extinction
- •Cooling of the Earth, cloud condensation nuclei, and DMSP
- •Chemical defense mechanisms of algae
- •The Antarctic and Southern Ocean
- •The grand experiment
- •Antarctic lakes as a model for life on the planet Mars or Jupiter’s moon Europa
- •Ultraviolet radiation, the ozone hole, and sunscreens produced by algae
- •Hydrogen fuel cells and hydrogen gas production by algae
- •REFERENCES
- •Glossary
- •Index
HETEROKONTOPHYTA, BACILLARIOPHYCEAE |
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Fig. 17.12 Pinnularia viridis. Left: Scanning electron micrograph of a cross section of a cleaned valve. Right: Atomic force micrograph of the surface of a cleaved area of a valve showing the 40–45 nm silica spheres that compose the valve. (From Crawford et al., 2001.)
Fig. 17.13 Schematic structure of silaffin and the polyamine side chains of silaffin, two molecules that control the precipitation of silica spheres in diatoms. (Adapted from Kroger et al., 1999.)
living diatoms appears to be protected by the layer of organic material that surrounded the frustule. After death, the silica usually dissolves (Bidle and Azam, 1999). In certain environments, however, the walls of planktonic diatoms may settle and accumulate on the bottom faster than they dissolve, thereby forming diatomaceous ooze.
Extracellular mucilage, biolfouling, and gliding
Diatoms produce five types of mucilaginous aggregation: (1) tubes, (2) pads, (3) stalks, (4) fibrils,
and (5) adhering films (Figs. 17.16, 17.17, 17.18) (Hoagland et al., 1993). Stalks, pads, and tubes are more common in freshwater diatoms than in marine diatoms (Staats et al., 1999).
A substantial part of the carbon fixed by benthic diatoms is secreted as extracellular mucilages (de Brouwer and Stal, 2002). The biofilms produced by the diatoms play an important part in stabilizing mud flats where the diatoms grow. In the open ocean, the mucilage produced by planktonic diatoms is the triggering mechanism in the formation of “marine snow”, which is sticky gelatinous aggregations of bacteria and algae (up to 100 mm in diameter) that create serious problems for fisheries (Alcoverro et al., 2000). The wind drives the marine snow onto the beaches,