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THE EXCRETION OF CARBON DIOXIDE BY RELAXED AND CONTRACTED SEA ANEMONES
1Zoological Laboratory of Harvard University.
The Journal of General Physiology
|October 30, 2009
Summary
The sea anemone Metridium marginatum exhibits significantly higher metabolism during contraction. However, its relaxed and contracted states show similar metabolic rates, suggesting tonus muscle function for sustained contraction.
Area of Science:
- Marine Biology
- Animal Physiology
- Biochemistry
Background:
- The sea anemone Metridium marginatum's metabolic processes are not fully understood.
- Investigating metabolic rates across different physiological states is crucial for understanding energy expenditure in marine invertebrates.
Purpose of the Study:
- To quantify the metabolic rate of Metridium marginatum in relaxed, relaxing, contracted, and contracting states.
- To determine if contraction and relaxation significantly alter the sea anemone's metabolism.
Main Methods:
- Metabolism was measured using an Osterhout respiratory apparatus.
- Carbon dioxide excretion per gram of sea anemone per second was the primary metric.
- Measurements were taken across four distinct physiological states: relaxed, relaxing, contracted, and contracting.
Main Results:
- Metabolic rates in relaxed and contracted states were comparable.
- The process of relaxing showed a similar metabolic rate to the relaxed state.
- The act of contracting demonstrated a significantly higher metabolic rate, approximately 50% greater than other states.
Conclusions:
- Metabolism is not unusually elevated during relaxation or in the contracted state.
- The active process of contraction involves a substantial increase in metabolic intensity.
- Sustained contraction without increased metabolism suggests Metridium marginatum possesses tonus musculature, possibly utilizing a catch mechanism.
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