Ecosystems Flashcards
Decomposers
Organisms which decomposes organic material.
Community
Multiple populations of species in a given area
Mutualism
Both species benefit
E.g. pollination
Commensalism
One species benefits and the other has no cost.
Competition
Competing for a common resource.
Predation
Any predictor prey realtionship
Parasitism
One species benefits while the other loses out.
E.g. isopod and fish
What are examples of dynamic changes to an ecosystem.
Predictor prey
Seasons
Tides
Erosion
Natural disasters
Producer
An organism which produces its own food through inorganic substances such as carbon dioxide and ammonia
What is a heterotroph
An organism which can’t manufacture its own food therefore finds its own food
What percentage of energy is of inappropriate wavelengths for transfer of energy in a plant.
50%
What percentage of energy is reflected from the surface of the leaf?
5%
What percentage of energy is absorbed for transfer of energy in a plant
40%
What percentage of energy passes through the leaf.
5%
What percentage of energy in a plant is lost to respiration.
5%
What percentage of energy in a plant is lost to photosynthesis?
33%
What percentage of energy in a plant is lost to storage (starch)?
2%
Why isn’t all of the energy from the sun transferred to each organism which eats another.
Energy is lost through:
Excretion
Death
Heat
Some biomass indigestible.
How can the amount of energy/number of organisms/biomass available to the next organism be represented?
With pyramids.
What is scale?
Amount of dry mass of organisms at each level of the food chain
What is biomass?
The mass of material in all living organisms
How do light banks increase productivity?
Can control duration of light causing longer growth periods
And is more efficient.
Crop rotations effects on productivity?
It adds nutrition to the soil.
Pest control and irrigation effect on productivity?
Less loss of biomass
Water is a limiting factor.
How can we maximise secondary productivity?
No waste food
No movement
Warmth
Antibiotics
Killed young
Disadvantages of maximising secondary productivity.
Restricted movement may cause osteoporosis
Unnatural conditions cause stress
What is a decomposer
An organism that eats dead organisms, fallen leaves etc and breaks them down into simpler materials.
What are animal decomposers called.
Detritivores
What are saprotrophs?
Release digestive enzymes into the environment so they can absorb them.
What is nitrogen fixation?
N2 —— NH3
Nitrification
NH3 —— NO2 And NO2 —— NO3
(Ammonia to nitrite) And (Nitrite to nitrate)
Denitrifying
NO3 —— N2
(Nitrate to nitrogen gas)
Ammonification
Conversion of nitrogen containing organic compounds into ammonia
What is azotobacter?
Bacteria in the soil that does nitrogen fixation
what is rhizobium?
Bacteria in nodules by legumes which do nitrogen fixation.
What is Nitrosomonas?
Free bacteria in the soil that does nitrification only in aerobic conditions.
NH4 to NO2
What is Nitrobacter?
Free bacteria in the soil that does nitrification only in aerobic conditions.
(NO2 to NO3)
What percentage of atmospheric gasses are nitrogen?
78%
How does carbon get released back into the air in the carbon cycle?
Respiration and combustion
Were is carbon stored in the carbon cycle?
Plants, animals, microorganisms and fossils
How does carbon leave the atmosphere in the carbon cycle?
Photosynthesis
How does carbon enter decomposers in the soil?
Death and decay and unite and faeces
What is the Haber process?
The artificial fixation of nitrogen
What is assimilation
The uptake of nitrates by plants.
What is the only way of releasing nitrogen back into the atmosphere?
Denitrification.
What are the three ways of taking nitrogen from the air to ammonia in the soil?
Nitrogen fixation, the Haber process and atmospheric fixation.
