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Bacteria
B
Bacillariophyta (syn. Bacillariophyceae, diatoms), phylum of the kingdom
Protoctista, unicellular algae with cell walls of amorphous silica, formed by two
halves that close together as lid and box, called the frustules. The cells range
from 2 Ilm to a few mm. Some of them form chains of up to 1 cm or more.
Diatoms contain the pigments chlorophyll-c and fucoxanthin, and store carbohydrate as fluid chrysolaminarin. They can be divided into mainly benthic, elliptic so-called pennate diatoms, and usually planktonic centric diatoms which have
radial-symmetric frustules. As a group, diatoms are adapted to higher nutrient supplies than other algae, and dominate the phytoplankton in upwelling regions. Chaetoceros, Nitzschia, Rhizosolenia, and Thalassiosira are planktonic
genera. Navicula is a benthic genus. Navicula and relatives move on and in
the substrate by means of mucilage extrusion. This contributes to the consolidation of young sediments. The rich fossil record of diatoms starts in the
Jurassic; they are used extensively for biostratigraphy and paleoecology.
Bacillariophyta. (Tardent 1993)
back-arc basin ~marginal basin.
background radiation ~radiation, background.
backwash ~wave approach.
Bacteria (bacteria) uni-cellular prokaryote organisms, that form the kingdom
Monera. Their size varies from cells as small as 0.1 Ilm in width to more than
5 Ilm in diameter. Several distinct shapes of bacteria can be recognized. A
spherical or egg-shaped cell is called a coccus, a cylinder shape is called a
Bacteria
B
Bacillariophyta (syn. Bacillariophyceae, diatoms), phylum of the kingdom
Protoctista, unicellular algae with cell walls of amorphous silica, formed by two
halves that close together as lid and box, called the frustules. The cells range
from 2 Ilm to a few mm. Some of them form chains of up to 1 cm or more.
Diatoms contain the pigments chlorophyll-c and fucoxanthin, and store carbohydrate as fluid chrysolaminarin. They can be divided into mainly benthic, elliptic so-called pennate diatoms, and usually planktonic centric diatoms which have
radial-symmetric frustules. As a group, diatoms are adapted to higher nutrient supplies than other algae, and dominate the phytoplankton in upwelling regions. Chaetoceros, Nitzschia, Rhizosolenia, and Thalassiosira are planktonic
genera. Navicula is a benthic genus. Navicula and relatives move on and in
the substrate by means of mucilage extrusion. This contributes to the consolidation of young sediments. The rich fossil record of diatoms starts in the
Jurassic; they are used extensively for biostratigraphy and paleoecology.
Bacillariophyta. (Tardent 1993)
back-arc basin ~marginal basin.
background radiation ~radiation, background.
backwash ~wave approach.
Bacteria (bacteria) uni-cellular prokaryote organisms, that form the kingdom
Monera. Their size varies from cells as small as 0.1 Ilm in width to more than
5 Ilm in diameter. Several distinct shapes of bacteria can be recognized. A
spherical or egg-shaped cell is called a coccus, a cylinder shape is called a