heterocyst

cell

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June 29, 2026

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A heterocyst is a specialized, thick-walled cell found in certain cyanobacteria (blue-green algae). These cells are crucial for nitrogen fixation, a process that converts atmospheric nitrogen into a usable form for plants. Heterocysts are impermeable to oxygen, creating an anaerobic environment essential for the nitrogen-fixing enzymes to function. This process is vital for the nitrogen cycle and supports plant growth, particularly in environments like rice paddies where they can reduce the need for nitrogen fertilizers. Heterocysts are a type of dormant cell, similar to endospores and cysts, which help bacteria survive adverse conditions.1234

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blue-green algae
…that have specialized cells called heterocysts. The heterocysts are thick-walled cell inclusions that are impermeable to oxygen; they provide the anaerobic (oxygen-free) environment necessary for the operation of the nitrogen-fixing enzymes. In Southeast Asia, nitrogen-fixing cyanobacteria often are grown in rice paddies, thereby eliminating the need to apply nitrogen fertilizers.
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…that have specialized cells called heterocysts. The heterocysts are thick-walled cell inclusions that are impermeable to oxygen; they provide the anaerobic (oxygen-free) environment necessary for the operation of the nitrogen-fixing enzymes. In Southeast Asia, nitrogen-fixing cyanobacteria often are grown in rice paddies, thereby eliminating the need to apply nitrogen fertilizers.
Read More