Biology · Oct / Nov 2019 · Paper 11 · Question 6

A small mountain lake has aquatic plants growing underwater on the lake bed. Shortly after heavy rainfall the mud on the lake bed becomes churned up and the water level rises. Why does this cause the rate of photosynthesis of these plants to fall?

1. Aextra carbon dioxide
2. Bextra dissolved nitrates
3. Clower light intensity
4. Dlower oxygen concentration

As printed in the paper