Ecosystems (OCR A-Level Biology A): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
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Practise the questions
10 questions from this quiz
What key difference exists between elements and energy in ecosystems?
What key difference exists between elements and energy in ecosystems?
Elements are finite & recycled; energy flows
Which carbon reservoir contains the largest amount of stored carbon?
Which carbon reservoir contains the largest amount of stored carbon?
Sedimentary rocks (limestone & chalk)
In which form do autotrophs absorb nitrogen from their environment?
In which form do autotrophs absorb nitrogen from their environment?
Nitrate ions (NO3-)
Why is atmospheric dinitrogen (N2) highly unreactive?
Why is atmospheric dinitrogen (N2) highly unreactive?
It has a triple covalent bond (N≡N)
Which bacteria oxidize ammonia to nitrite ions in the first stage of nitrification?
Which bacteria oxidize ammonia to nitrite ions in the first stage of nitrification?
Nitrosomonas
What is the role of Nitrobacter in the nitrogen cycle?
What is the role of Nitrobacter in the nitrogen cycle?
Oxidizes nitrite ions (NO2-) to nitrate
Why does nitrogen fixation require anaerobic conditions?
Why does nitrogen fixation require anaerobic conditions?
Oxygen deactivates nitrogenase enzyme
What is the function of leghaemoglobin in legume root nodules?
What is the function of leghaemoglobin in legume root nodules?
Binds O2 to maintain anaerobic conditions
Under what conditions does denitrification occur?
Under what conditions does denitrification occur?
Anaerobic/waterlogged soils
What is ammonification?
What is ammonification?
Production of NH3 by microorganisms