Topic 13 - Energy and Ecosystems Flashcards
Producers
Photosynthetic organisms that can manufacture organic substances using solar energy, water, carbon dioxide and mineral ions.
Consumers
Organisms that feed on other organisms, rather than using solar energy to produce their own energy
Primary consumers
Organisms that directly eat producers
Secondary consumers
Organisms that eat primary consumers
Tertiary consumers
Organisms that eat secondary consumers
Saprobionts
A group of organisms that break down complex materials in dead organisms, into more simple molecules. They release valuable minerals and elements in a way that can be absorbed by bacteria
Food chain
The feeding relationship from producers to tertiary consumers along each trophic level
Trophic level
Each level of the food chain
Food web
A true representation of consumption within a habitat. Unlike a food chain, this shows how energy can be transferred throughout the whole environment
Biomass
The total mass of living material in a specific area at a given time. Measured in dry mass per area in a given time
Calorimetry
A process in which biomass can be measured, where a sample of dry material is weighed then burned in a seal chamber in the presence of pure oxygen. Measured in kJ kg^-1
Net primary production
The chemical energy store remaining once respiratory losses have been taken into account (GPP - R)
Gross primary production
The total quantity of the chemical energy store in plant biomass, this does not consider the respiratory losses of the plant
Faeces and Urine
Another factor which accounts for the net production of consumers, other than respiratory losses
Percentage efficiency
(Energy available after energy transfer/ Energy available before energy transfer) x 100
Movement
A factor that is restricted in intensive farming so that less energy is used in muscle contraction
Temperature
A factor that is maintained in intensive farming so that there is less heat loss in the body
Feeding
A factor that is controlled in intensive farming so that animals have maximum growth with the least wastage
Predators
A factor that is removed in intensive farming so that there is no loss of organisms to the food web
Nitrification
The conversion of ammonium ions into nitrate ions through a two step process involving nitrifying bacteria:
- Oxidation of ammonium ions to nitrite ions
- Oxidation of nitrite ions to nitrate ions.
Ammonification
The production of ammonia from organic nitrogen containing compounds (dead material) by saprobionts, allowing for ammonium ions to form in the soil.
Nitrogen fixation
The process by which nitrogen gas is converted into nitrogen-containing compounds by two different microorganisms:
- Free living bacteria that reduces gaseous nitrogen to ammonia, to process into amino acids
- Mutualistic bacteria that love in the nodules of plant roots, obtaining carbohydrates from the plant in return for amino acids.
Denitrification
The process by which nitrates are converted into gaseous nitrogen. This is only done in anaerobic conditions by denitrifying bacteria.
Deposition
Rain causes phosphates to be deposited in rocks
Erosion
Weathering of rocks cause the release of phosphate ions into soil and water
Absorption
Plants take up the phosphate ions from the soil and water
Excretion and Decomposition
Once animals have taken up phosphates from consuming plants, they release the phosphate back into the water
Excretion
Once animals have taken up phosphates from consuming plants, they release the phosphates back into the soil
DNA
Where phosphates are incorporated into animals upon consumption of plants
mycorrhizae
Associations between certain types of fungi and the roots of most plants. They act like a sponge to hold water and minerals which then allows for the fungi and plants to survive in extreme weather. These allow for a mutualistic relationship between the plants and fungi.
Organic fertilisers
Fertilisers that consist of dead and decaying remains of plants and animals, including the excretion of animals
Inorganic fertilisers
Fertilisers that are mined from rocks, converted into unique forms and blended for an appropriate ration of NPK
Reduced species diversity
Nitrogen rich soils favour the growth of grass and other fast growing species. This increases the competition and slower growing plants die
Leaching
The running of excess fertilisers into groundwater
Eutrophication
Where leaching causes fertilisers to run into watercourses
The process of eutrophication:
1) Excess fertiliser runs into water from leaching. Removing nitrogen as a limiting factor, allowing for the growth of plants and algae
2) Algal bloom occurs on the surface of the water, forming a dense layer of algae
3)The algae absorbs all of the solar energy, blocking the energy from reaching the lower surface
4) The lack of solar energy prevents the photosynthesis of plants - they die
5) Saprobionts utilise the deal material for food, so reproduce and use more oxygen
6) Less oxygen prevents organisms that undergo aerobic respiration from survival - they die
7) Anaerobic organisms thrive, further decomposing dead material, making the water putrid.
What is an ecosystem
A biological community of interacting organisms and their physical environment. Including all the living and non living things in an area
Cellular respiration
The process by which producer release their chemical energy
What is excess chemical energy stored as in plants?
Starch
