noun
- A photosynthetic bacterium that contains chlorophyll and produces oxygen, formerly classified as blue-green algae.
Usage: scientific/technical term; plural: cyanobacteria
Examples
- Cyanobacteria are among the oldest known fossils, dating back over 3 billion years.
- The cyanobacterium Nostoc is commonly found in freshwater environments.
- Some cyanobacteria can fix nitrogen from the atmosphere, making them important in ecosystems.
- Harmful algal blooms are sometimes caused by excessive growth of cyanobacteria in polluted waters.
- Scientists study cyanobacteria because they were responsible for producing Earth's early oxygen atmosphere.