5.1
what are producers?
5.1
what are consumers? 3 different types?
5.1
what are the two main decomposer groups?
5.1
what are decomposers and what do they contribute to?
5.1
what is a trophic level?
5.1
what do the arrows on food chain diagrams represent?
5.1
what is a food web? what can be said about the feeding inter-relationships of organisms?
5.2
why is most of the sun's energy not converted to organic matter by photosynthesis?
5.2
what is gross production?
5.2
what is net production?
5.2
what are four reasons why there is a low energy transfer between each trophic level?
5.2
what are three consequences of the inefficiency of energy transfer between trophic levels?
5.2
how do you calculate energy transfer?
5.3
how is a pyramid of number drawn?
5.3
what are two drawbacks of using a pyramid of number to describe a food chain?
5.3
how is a pyramid of biomass made? what is biomass and units?
5.3
why may a pyramid of biomass be unreliable? possible way to overcome this? further problems?
5.3
what do pyramids of biomass and numbers both show?
5.3
how is a pyramid of energy made?
5.3
how is data collected for a pyramid of energy? drawbacks?
5.3
why are pyramids of energy more reliable than pyramids of biomass?
5.3
what are the units of measurement for energy flow in pyramids of energy?
5.4
what is an agricultural ecosystem made up of?
5.4
what is the main aim of agriculture?
5.4
what is productivity?
5.4
what is gross productivity?
5.4
what two things are net productivity affected by?
5.4
explain the difference between natural and agricultural ecosystems in terms of energy input
5.4
explain the difference between natural and agricultural ecosystems in terms of productivity
5.4
draw up a comparison table for natural and agricultural ecosystems (seven points!)
5.5
what are pest?
5.5
what are pesticides?
5.5
what four things should an effective pesticide be?
5.5
what is biological control?
5.5
what are two disadvantages of biological control? three advantages?
5.5
what are three disadvantages of chemical control?
5.5
what do integrated pest-control systems aim to do?
5.5
what six things do integrated pest control systems involve?
5.5
explain how controlling pests affects productivity?
5.6
intensive rearing of domesticated livestock aims to?
5.6
describe four ways 'factory farming' increases energy-conversion rate
5.6
what two other options are available other than factory farming?
5.6
describe six features of intensive rearing of livestock
5.6
what are three direct effects of intensive food production?
5.6
what are two indirect effects of intensive food production?
5.6
what are four other conservation techniques?
5.6
what economic issue does intensive rearing present?