Genetics and ecosystems (Module 6) Flashcards
Producer
Green plants that convert simple molecules into complex organic molecules using the sun’s energy
Consumer
Animal or plant that feeds on organic molecules made by a producer
Decomposer
saprophytic bacteria and fungi that break down complex molecules in other organisms once they die, releasing simple molecules for other organisms to use
Detritivore
Feed on particles or decaying organic matter, releasing the energy locked up in them to other living organisms
Saprotrophs
Organisms such as bacteria and fungi that feed on dead and decaying matter
Geochemical
From rocks and ocean deposits
Eutrophication
Algae grow Light blocked out - kill bigger plants Bacteria decay dead plants Bacteria use up all oxygen Fish die
Ammonification
Production of ammonia from organic ammonium containing compounds such as ammonium nitrate, urea, proteins, nucleic acids and vitamins
Nitrification
Oxidation of ammonium ions (NH4+) to nitrates (NO3-)
Two stage process
. Ammonia to nitrite
. Nitrite to nitrate
Denitrification
Nitrate converted back to nitrogen gas
Occurs in water logged soils with little oxygen in anaerobic conditions
Leaves soils lacking in nutrients
Nitrogen fixing
Conversion of atmospheric nitrogen in soils to nitrate or ammonium
. Lightning - nitrogen +oxygen = nitrates
. Haber Process - Nitrogen + hydrogen = ammonia
. Microorganisms - free living in soil, in mutualistic relationship in legumes
Assimilation
When a molecule becomes part of an organism (nitrates become part of protein in plants)
Leghaemoglobin
Molecule that absorbs oxygen in root nodules to make anaerobic conditions that allow nitrogen fixing
Nitrogenase
Enzyme used in Rhizobium bacteria to convert nitrogen gas into ammonium ions, using ATP energy
Nitrosommonas
Free living nitrifying bacteria - ammonium to nitrite
Nitrobacter
Free living nitrifying bacteria - nitrite to nitrate
Rhizobium
Nitrogen fixing mutualistic bacterium in legumes
Abiotic factors
non-living components of an ecosystem that affect other living organisms
Biotic factors
Environmental factors associated with living organisms in an ecosystem that affect each other (predation, disease)
Ecosystem
Community of animals, plants and bacteria interrelated with the physical and chemical environment
Biomass transfer
Transfer of biomass from one trophic level to another
Trophic level
The level at which an organism feeds in a food chain
Productivity
Rate of production of new biomass by producers
Climax community
Final stable community that exists after succession has occurred
