Prorochlorococcus is currently known as "the smallest photosynthetic autotroph on the earth".
At present, cyanobacteria classified by bacteria are unicellular organisms with a diameter of about 500 to 700 nanometers. At the same time, it is also the largest number of photosynthetic autotrophs on the earth last year (2.8× 10 27 to 3.4× 10 27), and the cumulative carbon content is about1.71000 million tons.
Autotrophic organisms can be divided into two categories: photoautotrophic and chemoautotrophic. Higher plants and cyanobacteria (primitive unicellular algae with photosynthetic pigments in their cells) can carry out photosynthesis, which belongs to photoautotrophic (photosynthesis). Nitrifying bacteria are chemoautotrophic, and they can use the chemical energy released when inorganic substances are oxidized.
Morphological characteristics:
Chlorococcus is a perennial submerged plant. Algae are filamentous aggregates, mostly forming loose spherical or irregular green masses with a diameter of 1-30 cm, floating on the bottom of the water and fixed on the substrate together with basal cells. Filaments are slender, 1 to 3 cm long, branched, dark green, slender and elastic; ? The top branches alternate, the base branches are opposite, the base is at right angles to the main shaft, and some branches on the top page are at acute angles to the main shaft.
The cell is long and cylindrical, and its cell wall is thick. It is divided into three layers, the inner layer is cellulose, the middle layer is pectin, and the outer layer is insoluble substance, namely chitin. There are 1 vacuole in the center of the cell, and the chromophore is reticulate and wall-born, containing most protein nuclei, and the cell is multinucleate. When a cell divides, a 1 ring is generated in the middle of the cell sidewall, which grows towards the center and divides the cell into two.
Branching occurs on the top side of 1 cell, which makes branching usually binary. Branching usually occurs in some cells near the top of filaments. Spores have flagella of equal length.