AICE Marine Science AS Level Exam with Questions and Answers

AICE Marine Science AS Level Exam with Questions and Answers phosphorus ANSWER abiotic- 1. phosphorus us weathered from sedimentary rock, apatite containing calcium phosphate - it is brought into the sea by runoff from land/rivers - present in water as phosphate ion biotic- 2. as phosphate ions, it enters marine organisms such as fish, to be used from bones and teeth as week s for DNA/RNA and ATP/ADP out of biotic, to abiotic- 3. once an organism dies and sinks to seafloor 4. calcium can be compressed back to apatite 5. land can be uplifted or sea level may fall which will expose the rock on land and allow weather and erosion to remove phosphate from the rock 6. can also be brought up by upwelling nitrogen ANSWER abiotic- 1. runoff from agricultural waste/chemical/fertilizer/pollutants wash into sea as nitrates 2. atmospheric dissolution- dissolves nitrogen as N2 which will be fixed by nitrogen fixing bacteria to ammonia, then by the process of nitrification done by bacteria convert ammonia into nitrite, the nitrate biotic- 3. assimilation by algae/phytoplankton 4. consumed by primary consumers, secondary, etc