Important terms and definitions - energetics
- Q10:Rate of physiological processes at a particular temperature / Rate of physiological processes at a temperature that is 10 degrees lesser
- Metabolic theory of Ecology: Temperature has a consistent effect on Ecological and Evolutionary processes. Usually, higher the temperature, higher the rate of metabolism.
- Homestasis: The ability of organisms to adjust their internal body temperature and maintain it within the physiological range (that can support life).
- Ectotherms: Species that receive heat from external agents to maintain their body temperature.
- Endotherms: Species that produce heat internally (by metabolic activities) to maintain their body temperature.
- Ecological Efficiency: Efficiency of nutrient transfer from a lower trophic level to the higher, in an ecosystem. It is usually between 5 to 20% .
- Photosynthetic Efficiency: Percentage of energy in sunlight that is converted to NPP - usually 1-2%
- Water use efficiency: Number if grams of dry matter produced per kg of water transpired.
- Nutrient use efficiency: Number if grams of dry matter produced per g of nutrient assimilated.
- Compensation point: Light intensity at point at which NPP = 0. Respiration = Photosynthesis.
- Saturation point: Point at which increase in light intensity no longer increases NPP.
- Sensible heat: Heat of a substance by virtue of its temperature
- Latent heat: Heat possessed by a substance due to its phase. (A gas at 100 degree Celsius has more energy than a liquid at the same temperature)
- Chemautotrophy: Ability by which organisms capture energy from reduced inorganics (chemicals) rather than CO2.
- Metabolism: Oxidation of these high energy reduced chemicals
- Aerobic respiration: Uses oxygen as reducing agent to break down chemicals and release energy.
- Anaerobic respiration: Uses NO3,SO4, Fe, CO2 as reducing agents to do the same.
- Methanogenesis: Uses CO2 as reducing agent and converts it to methane.
Trophic Pyramid:
page revision: 4, last edited: 08 Nov 2009 00:32