At present, cyanobacteria, classified in the bacterial world, are single-celled 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.
brief introduction
Plants are called producers of food chain because they can use inorganic substances to produce organic substances and store energy through photosynthesis. By eating, consumers in the food chain can absorb the energy stored by plants, with an efficiency of about 30%. For almost all creatures in the biological world, this process is the key to their survival. Photosynthesis is very important for the carbon and oxygen cycle on the earth.
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