Reactive oxygen species (ROS)
noun phrasePronunciation: /riˈæktɪv ˈɒksɪdʒən ˈspiːʃiːz/
Highly reactive molecules containing oxygen, such as superoxide anions, hydrogen peroxide, and hydroxyl radicals, produced during aerobic metabolism and stress conditions. Excessive ROS accumulation causes cellular damage through oxidative stress but serves signaling functions at physiological levels.
Plain English
Unstable oxygen-containing molecules produced during stress that can damage cells but also send important signals.
Etymology & History
Usage
"Under heat stress, ROS accumulation triggered mitochondrial dysfunction and activated programmed cell death pathways."
Style guide notes: Always use the abbreviation ROS after initial expansion; specify ROS types (superoxide, hydrogen peroxide) when discussing specific mechanisms.
Also known as
Contrasted with
Related Terms
Frequently Asked Questions
Why do plants produce ROS during stress?
ROS production increases during stress due to disrupted photosynthetic and respiratory electron transport chains and serves as stress signals.
How do plants protect themselves from ROS damage?
Plants employ enzymatic antioxidants like superoxide dismutase and catalase, plus non-enzymatic antioxidants like ascorbate and glutathione.
Why Test Candidates on This?
ROS metabolism is critical for understanding plant stress responses across all abiotic stress categories and is heavily tested in physiology assessments.
Required skill level: Mid