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43 Cards in this Set
- Front
- Back
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What is an ecosystem? |
Includes all the organisms living in a particular area and all the abiotic conditions |
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What are producers? |
Organisms which make their own food |
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What is biomass? |
The biological molecules makes up the plants biomass made by sugars in photosynthesis. Biomass is the chemical energy stored in a plant |
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What is the diagram of the food chain? |
Tertiary consumers ⬇️ Secondary consumers ⬇️ Primary consumers ⬇️ Producers |
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What are the two methods that can be used to measure biomass? |
Method 1: •sample of organism is dried in oven set at a low temperature •sample is weighed at regular intervals until mass is constant showing that all the water is lost •mass of carbon is 50% of dry mass Method 2: •burn sample of biomass using calorimeter •energy released is used to heat up water •temperature change of water can be used to calculate chemical energy of biomass |
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What is dry mass? |
Mass of organism with water removed |
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What is gross primary production? |
Total chemical energy converted from light energy by plants in a given area |
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How much of GPP is lost to respiration? |
50% |
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What is the net primary production? |
Chemical energy available to plant for growth and reproduction which is stored on insta biomass. It is also energy available to organisms at next trophic level •can be expressed as a rate- total amount of chemical energy (or biomass) in a given area at a given time Called primary productivity when expressed as rate Units- kJha-1year-1 : kJm-2yr-1 |
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What is the equation for calculating npp? |
Npp- gpp - rl |
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How do consumers get energy? |
Consumers get energy by ingesting plant material or eating animals which have eaten plant material |
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How much of the energy from previous consumer is lost? |
90% |
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What are the three ways energy is lost from consumer to consumer? |
-plants don’t eat bones or roots so don’t get energy from this -ingested material may be indigestible so excreted as faeces -some energy is lost to surroundings by respiration it urination |
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What is the net production of consumers? |
Energy available in consumers biomass to next trophic level |
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How to calculate net production of consumer? |
N = I - (F + R) I- chemical energy in ingested material F-chemical energy lost in faeces R- respiratory loss Can also be called secondary production |
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What do farming practices aim to do? |
Increase amount of energy available for human consumption |
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What do farming practices aim to do? |
Increase amount of energy available for human consumption |
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What are two things farmers do to increase energy available for humans? |
•reduce energy lost to other organisms like pests •reduce energy lost through respiration |
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What do farming practices aim to do? |
Increase amount of energy available for human consumption |
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What are two things farmers do to increase energy available for humans? |
•reduce energy lost to other organisms like pests •reduce energy lost through respiration |
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What are the three ways farmers reduce energy lost to other organisms? |
1) use pesticides- pesticides kill pests which feed on crops. There is less biomass lost, more crop produced so npp is produced. Also kills unwanted plant species which cancels out any competition whixhbagain increases npp 2) use biological agents like parasites which lay eggs on a pest insect eventually killing them. Bacteria produce toxins which kills the pests 3) a natural predator is introduced to the crop which feeds on the pests |
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What do farming practices aim to do? |
Increase amount of energy available for human consumption |
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What are two things farmers do to increase energy available for humans? |
•reduce energy lost to other organisms like pests •reduce energy lost through respiration |
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What are the three ways farmers reduce energy lost to other organisms? |
1) use pesticides- pesticides kill pests which feed on crops. There is less biomass lost, more crop produced so npp is produced. Also kills unwanted plant species which cancels out any competition whixhbagain increases npp 2) use biological agents like parasites which lay eggs on a pest insect eventually killing them. Bacteria produce toxins which kills the pests 3) a natural predator is introduced to the crop which feeds on the pests |
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What are the two ways farmers reduce energy lost through respiration? |
•restrict movement of the animal so less energy is lost through movement. Do this by keeping animals in confined spaces •keep the confined spaces at a warm temperature so animals don’t waste energy as heat energy |
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What is a natural ecosystem? |
An ecosystem which hasn’t been changed due to human activity |
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Describe sapriobiotic nutriton |
Saprobiants are types of decomposers which feed on dead organsisms and their waste. They secrete enzymes where they digest food externally and then absorb the nutrients (extracellular digestion.) during this process, organic material is converted to inorganic material Some fungi form sambiotic relationships with plant roots. These relationships are mycorrhizal These fungi are made up of thin long strands which connect to plant roots. Increase sa of plant roots increasing nutrient and water uptake. In return fungi obtain carbohydrates from plants |
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Describe the process of the nitrogen cycle |
Nitrogen fixation; nitrogen gas is converted into nitrogen compounds in plants and animals by bacteria. Bacteria convert nitrogen gas into ammonia and form ammonium ions in solution in plants. These bacteria grow inside root nodules and have a mutualisric relationship as they provide nitrogen compounds to plants and plants provide carbohydrates Ammonification: saprobionts convert nitrogen compounds in dead organic matter to ammonia Nitrification: nitrifying bacteria (nitrosomonas) converts ammonia ions in soil into nitrites. Other nitrifying bacteria convert nitrites into nitrates Denitrification: denitrifying bacteria converts nitrates in soil to nitrogen gas by using them for respiration. Done in anaerobic conditions such as in waterlogged soils |
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Describe the phosphorus cycle |
Plants and animals need phosphorus for phospholipid bilayer, Dna and atp. Phosphorus is going on rocks and dissolved in oceans as Po4(3-) 1)phosphate ions in rocks are released into soils by weathering 2) plant roots-take up the phosphorus. Mycorrhizal increase this uptake 3) transferred through food chains 4)saprobionts feed on the organic matter releasing phosphorus intonsoil 5)weathering of rocks release into oceans so aquatic compounds take up this |
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Describe the phosphorus cycle |
Plants and animals need phosphorus for phospholipid bilayer, Dna and atp. Phosphorus is going on rocks and dissolved in oceans as Po4(3-) 1)phosphate ions in rocks are released into soils by weathering 2) plant roots-take up the phosphorus. Mycorrhizal increase this uptake 3) transferred through food chains 4)saprobionts feed on the organic matter releasing phosphorus intonsoil 5)weathering of rocks release into oceans so aquatic compounds take up this |
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Why are nutrients lost by crop harvesting? |
When crops are harvested, they are removed from the soil so the minerals can’t be replaced by decomposition. Also when animals are slaughtered or transferred to another field there is no organic matter for decomposers to feed on |
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Describe the phosphorus cycle |
Plants and animals need phosphorus for phospholipid bilayer, Dna and atp. Phosphorus is going on rocks and dissolved in oceans as Po4(3-) 1)phosphate ions in rocks are released into soils by weathering 2) plant roots-take up the phosphorus. Mycorrhizal increase this uptake 3) transferred through food chains 4)saprobionts feed on the organic matter releasing phosphorus intonsoil 5)weathering of rocks release into oceans so aquatic compounds take up this |
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Why are nutrients lost by crop harvesting? |
When crops are harvested, they are removed from the soil so the minerals can’t be replaced by decomposition. Also when animals are slaughtered or transferred to another field there is no organic matter for decomposers to feed on |
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What are the two types of fertiliser? |
Artificial: inorganic in the form of powder or pellets Natural- organic in form of manure |
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Describe the phosphorus cycle |
Plants and animals need phosphorus for phospholipid bilayer, Dna and atp. Phosphorus is going on rocks and dissolved in oceans as Po4(3-) 1)phosphate ions in rocks are released into soils by weathering 2) plant roots-take up the phosphorus. Mycorrhizal increase this uptake 3) transferred through food chains 4)saprobionts feed on the organic matter releasing phosphorus intonsoil 5)weathering of rocks release into oceans so aquatic compounds take up this |
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Why are nutrients lost by crop harvesting? |
When crops are harvested, they are removed from the soil so the minerals can’t be replaced by decomposition. Also when animals are slaughtered or transferred to another field there is no organic matter for decomposers to feed on |
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What are the two types of fertiliser? |
Artificial: inorganic in the form of powder or pellets Natural- organic in form of manure |
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What are the two issues with fertilisers? |
•leaching- too much fertiliser means they can be washed into rivers and lakes and clog up waterways and can lead to eutrophication •adding fertiliser can mess up balance of nutrients in soil so can lead to death of plants |
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Describe the phosphorus cycle |
Plants and animals need phosphorus for phospholipid bilayer, Dna and atp. Phosphorus is going on rocks and dissolved in oceans as Po4(3-) 1)phosphate ions in rocks are released into soils by weathering 2) plant roots-take up the phosphorus. Mycorrhizal increase this uptake 3) transferred through food chains 4)saprobionts feed on the organic matter releasing phosphorus intonsoil 5)weathering of rocks release into oceans so aquatic compounds take up this |
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Why are nutrients lost by crop harvesting? |
When crops are harvested, they are removed from the soil so the minerals can’t be replaced by decomposition. Also when animals are slaughtered or transferred to another field there is no organic matter for decomposers to feed on |
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What are the two types of fertiliser? |
Artificial: inorganic in the form of powder or pellets Natural- organic in form of manure |
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What are the two issues with fertilisers? |
•leaching- too much fertiliser means they can be washed into rivers and lakes and clog up waterways and can lead to eutrophication •adding fertiliser can mess up balance of nutrients in soil so can lead to death of plants |
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Describe the process of eutrophication |
•fertiliser contains mineral ions washed into rivers and lakes •algae block sunlight from reaching plants •plants die •bacteria feed on dead plant matter which reduces o2 conc due to respiration •fish and other aquatic organisms die due to low dissolved oxygen concentration |
