Briefly describe the environmental effects of nitrogen fertilisers in a body of water
The nitrogen fertiliser would leach into the water. This would cause algae to grow exponentially on the surface of the water, therefore would reduce the amount of light available to plants below the surface. Light is the limiting factor.
The plants would die (as cannot photosynthesise) and saprobiotic organisms would feed off the dead plants, as well as use up the oxygen in the water. Oxygen is the limiting factor. Reduction in oxygen causes aerobic organisms in water to die. The water is now putrid.
HB
Related Biology A Level answers
All answers ▸When a nerve impulse arrives at a synapse, it causes the release of neurotransmitter from vesicles in the presynaptic knob. Describe how.
Guillain-Barré syndrome and multiple sclerosis both cause muscle weakness and loss of muscle function. Suggest and describe how the function of neuromuscular junctions will be affected by Guillain-Barré syndrome and multiple sclerosis.
Contrast the processes of facilitated diffusion and active transport. (3 marks)
Suggest why an increase in phosphate can be linked to embryonic growth.