Ocr A Level Biology Ecosystems Study Guide Graded A+

what is Denitrification? {Ans: nitrate ions are reduced by bacteria in anaerobic conditions to nitrogen gas (N2)}how to maximise energy input in crop plants? and livestock? {Ans: crops: Optimum planting distances between crop plants or provide light for greenhouse crops on overcast days livestock: provide good-quality feed}what are the five adaptations of pioneer speices? {Ans: 1)they can photosynthesis and produce their own energy 2)they can germinate seeds 3)can produce large quantites of seeds 4)they can tolerate extreme conditions 5)the ability to fix nitroogen in the atmosphere so adding to the mineral content to the soil.}what is a succession? {Ans: a series of communities that develop in an area over time}what are the main losses of energy from food chains? (6) {Ans: - heat - movement - waste - growth - urine - homeothermic (temperature control mechanisms)}what is Nitrogen fixation? {Ans: nitrogen gas is changed into ammonium ions by nitrogen-fixing organisms e..g Rhizobium}